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MOSTLY MOUNTAIN BIKES

SPORTS - RACING - HOCKEY
BIKES, TRIKES & MOUNTAIN BIKES

Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Sun Jul 25, 2010 4:15 am

CYCLING IS THE BEST IN EXERCISE, ITS GREEN, AND ITS FAST
A RECENT TEST DONE IN CALGARY INVOLVED 3 PEOPLE COMMUTING TO WORK IN NORMAL MORNING RUSH HOUR TRAFFIC.
THEY ALL STARTED FROM THE FISH CREEK CALGARY TRANSIT TRAIN STATION IN THE SOUTH END AND ALL GOING TO THE DOWNTOWN CORE.
ONE PERSON TOOK THE TRAIN. ONE PERSON DROVE THEIR CAR AND ONE PERSON RODE THEIR BIKE.
THE BIKE ARRIVED ABOUT 5 MINUTES SOONER THEN THE TRAIN RIDER AND THE PERSON DRIVING FINALLY SHOWED UP 15 MINUTES LATER.
THERE ARE A LOT OF VEHICLES IN THE MIDDLE OF THE TRAFFIC JAMS CARRYING ONLY ONE PERSON. WHAT A WASTE OF FUEL, MONEY, ENERGY AND TIME.
THE OLD EXCUSE OF NOT HAVING A SHOWER AT WORK SIMPLY MEANS CHOOSING APPROPRIATE CLOTHING AND ADDING EXTRA TIME TO YOUR TRIP SO THAT YOU ARE NOT WORKING TOO
HARD ON THE BIKE AND REQUIRE A SHOWER. THE EXTRA TIME AND SLOWER PACE ALSO MEANS THAT YOU WILL HAVE THE TIME TO CHECK OUT THE SCENERY AND ACTUALLY ENJOY
THE TRIP.

CYCLISTS BEWARE !!!
WATCH OUT FOR THE RICH PEOPLE'S CARS. THE MERCEDES, BMW'S, ESCALADE'S ETC.
THERE HAVE BEEN A NUMBER OF ACCIDENTS THAT HAVE BEEN IN THE MEDIA INVOLVING BIKES AND HIGH END VEHICLES.
THESE PEOPLE CAN "HIT AND RUN" AND NOT GET CHARGED WHERE AS AN AVERAGE PERSON DRIVING A HONDA WOULD BE CHARGED WITH MAN SLAUGHTER, VEHICLE IMPOUNDED AND LICENSE REVOKED.
A WOMAN DRIVING AN ESCALADE HIT A CYCLIST IN A BIKE LANE DOING CONSIDERABLE DAMAGE TO THE FRONT OF THE VEHICLE AND DRAGGED THE BIKE UNDER HER SUV FOR ABOUT 25 MILES TO HER HOME. THE CYCLIST DIED INSTANTLY. THE DRIVER WAS NOT CHARGED.
I HAVE BECOME MORE AWARE OF THESE TYPES OF VEHICLES WHEN CYCLING, SLOW DOWN AND GRAB HOLD OF THE BRAKE LEVERS JUST IN CASE.
ITS SAVED SOME PAIN A COUPLE OF TIMES RECENTLY.
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zappdog
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Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Sat Oct 02, 2010 1:35 am

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CRANK MONSTER II . . . Balsa Wood Bike Frame
The original Crank Monster aluminium frame is showing some wear and producing a few rattles as well as a stress crack showing on the bottom near the steering tube.
Its time for a new frame. Since I don't have a worthwhile alloy frame kicking around its time to play with a composite frame. This one will be made of a few materials on a very restricted budget.
Materials will be 4 ounce dense styrofoam core. Aluminium parts will be bonded to the core using automotive panel epoxy. Bottom bracket, steering tube and seat tube will be stolen off a cheap aluminium frame and epoxyed to the core then fibreglass wrapped. The main stress points will use carbon fibre uni-directional fibres 2" tape or similar on top of the fibreglass in as many layers as needed probably 4 layers on top of 4 fibreglass. Fibreglass is being used as a base with minimal carbon fibre simply due to costs. Using all carbon fibre would triple the cost. (see note at bottom about carbon fibre recycling) Epoxy resin will be used instead of fibreglass resin for the added strength. I was aiming for 1300 to 1500 grams for the frame but with extra fibreglass and balsa needed to be strong enough it will likely end up around 1500 to 1800 grams. Rear tire clearance is accounted for as well since I ride wide knobbies in the winter and summer slicks.
The frame style is closer to a road bike or track bike but it is designed for a mountain bike. It has the same dimensions and geometry as the aluminium frame. I used a plumb-bob and a 360 degree protractor to find all angles. Second pic shows drawing used as a base for designing that has the same critical measurements and geometry as the original Crank Monster frame. Front derailleur mounting boss might be eliminated and go with just the gears on the back. Designing a frame of this type makes including suspension much more difficult. It would be very hard to make suspension mounting points strong enough to handle the forces in a suspension. The pivots and mounting points are what are causing the noise now so I want to eliminate those problems and weight. I will be using the Suntour front suspension fork that is on the Crank Monster now. The frame jig and foam core will be done over the winter and the finished frame ready for spring 2011.

While visiting my favourite model and r/c hobby shop I stopped to check out the balsa wood for another project. I picked up a 1x1x36" piece and found there was very little flex to it. I know it handled being bent much better than a hunk of 4 ounce dense styrofoam would be able to handle. It is very strong in comparison with styrofoam (probably as much as 100 times ) and not much difference in weight. Therefore I may pursue using balsa instead or a combination of styrofoam and balsa using balsa as the core. Balsa is as easy to work as foam even using the same tools. It would be a few grams more weight than a foam core but many times stronger. I think 4 pieces of 1x1 laminated into a 1x4 with epoxy for the main beam then covered in foam and shaped then fibreglass etc in the frame shape of the drawing. Two triangulated 1x1/2 will go in the rear stays, one to the bottom of the seat tube and one to the bottom bracket as the core. Additional 1x1 balsa maybe added for the high stress areas as gussets. The same 4 ounce dense Styrofoam will be used to fill in the blank spaces and a 1/2" sheet over the balsa then shaped to frame dimensions.
Balsa may seem an unusual material to use but balsa is used in some small 2 and 4 passenger planes and avionics in numerous areas and in the floorpan of the Corvette Z06 sandwiched between fibreglass. Its more than just a model makers material. Its showing up as the core for many types of composites because of its strength and weight.

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Image The layout of the balsa I was able to get. 2 - 3 x 1/2 laminated with 2 - 1 x 1/2 to fill in to make up the 1 x 4 needed.
Note: this design is ongoing and drawings will likely change often.
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I'm finally kicking this frame project back into action. I started gathering materials. A small design change to the balsa layout since 1x1 wasn't available so I ended up with 1/2 x 3 which will be laminated the same way with the main beam of two 1/2 x 3 to give the same dimensions. An inch will have to be added in to make the four inch beam of the design. Maybe overlap the 1/2 x 3 by 1 inch and laminate in 1 inch pieces to produce the needed 1 x 4. The rear stay will get a 1/2 x 3 for the bottom bar so only a small 1/2 x 1 will be needed for the top brace.

GEARS
Well the Crank Monster II is coming along more in the design. I have committed to changing the whole drive train. Out with the open gears and derailleurs and in with an internal hub. After much research the Shimano Nexus Alfine S-GS500 8 speed internal hub is my choice. There will have to be a few changes to the frame design but I think it will be worth it. The Nexus model I got has a coaster brake built in which means back peddling for rear brakes and also that I can eliminate the back brake lever and cable. The frame will not have the brake boss pins so those two parts are gone from my design. This means there will be a cable to the gears most of which will be embedded into the frame and one front brake cable. Front brakes will stay the same.
The only change I will need to make to the frame design is to make some rear lugs that have a horizontal slot so I can adjust chain tension. Or the other option is to use a chain tensioner (more like a non-shifting rear derailleur) and a chain the same length as with a gear cluster. The rear dropouts I planned on using would work good for an open gear and derailleur system but no way to adjust chain length being vertical cutouts. I also have to go to a single gear crank which saves having another derailleur, cable and two more chainrings.
It will be a fair bit more expensive than just replacing the back wheel and gear controls with open gears and derailleur. The Nexus hub with a matching shifter runs about $400 (CDN) then it still needs a rim and spokes plus the cost of a single gear crankset. A rim and spokes will be assembled by my local Bike Shop. I built those sweet wheels on the Crank Monster but I don't want to spend up to 500 to match that quality. The titanium spokes are ridiculous in price these days and a more common brand name rim with stainless steel spokes will be more than enough wheel for my needs. Because of the coaster brake I can use a rim for disc brakes instead of rim clampers so that will make for a cleaner look.
Costs will run about $800 total. Hub 320 and shifter 60, wheel build 200 and a decent single gear crank 100. The last 100 is for frame materials.
Of course I will be using it on the Crank Monster until the new frame is done.
It seems like a pretty expensive gear change but then I did spend 1400 on a $500 bike to create the Crank Monster 7 years ago.
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Note : used carbon fibre can be re-cycled by soaking in a solvent of the appropriate type or burned off. The carbon fibres are not affected by baking or low temp burning the resins out of it and most solvents. Once resin is burned and powdery, flex and shake and blow off with air, rinse and dry. I would avoid pieces that are discarded because of cracks since the fibres would be broken. If you put a value to your time it works out not much cheaper than buying new unless it is a large amount. Woven cloth would be the easiest to find. Recycling carbon fibre requires appropriate safety gear such as goggles, mask and thick latex gloves with lots of ventilation preferably outside. The resins produce lots of mildly toxic smoke when burned. The proper way to burn it off would be to use an enclosed oven with a heavily filtered exhaust utilising wet filtration and carbon particle filters. Recommended if doing lots.

Frame Build
First layout of parts and balsa. I drew out the angles and dimensions on the plywood first. A few parts need to be trimmed to fit as well as some duplicate parts for other wheel stay and building up to 1" thick. The main beam will fit into the down tube with a tenon joint for added strength. All joints and connections will be with 2 part 5 minute epoxy.
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The top and bottom 1x1/2 beams of the rear stays. The 1/8 plywood will add considerable strength to all the joints.
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Pen marks show size of plywood insert. Also note alignment marks. To make the cutouts for the plywood I drilled 1/8 holes along the outlline of the plywood plug along the centre line then used a razor knife to cut out. I'm glad its balsa. Oh ya, just for a giggle, the plywood is from a peach box. Parts of it got used in a certain canard wing jet model I did a few years back, shown elsewhere in this forum.
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Rear stay showing bracing epoxied in.
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Main beam to seat post mortise and tenon joint before epoxy.
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Both the rear stays and the mortise and tenon joint turned out to be many times stronger than I expected. I stood both rear stays on edge and did a hand stand on them (I'm 140 lb.) Very strong stays.
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Yet another lay-out to check everything. Rear stays will get sunken into the seat post about half the thickness (1/4"). A jig is next to stand up the frame and align everything before attaching the rear stays. Note board between rear stays to keep it at 133 mm apart, same width as a back wheel.
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Rear stays showing styrofoam filling in spaces and to sandwich both sides. Inside of stays will be cut back lots but 1" foam was all that was available. Have lots of Olfa knife blades handy.
Note cutouts to allow for aluminum dropout pieces. Any small gaps will be filled with 2 part epoxy adhesive. Any larger gaps elsewhere will get 2 part gel epoxy adhesive which won't drip or droop in thicker applications.
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Note slot in main beam for plywood biscuit in angled braces, matching slot on other edge of main beam. Rear stay in background has had foam sliced to a half inch.
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Black squares at brace joints are outline of plywood biscuits inside.
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Frame with spaces filled in and is a 1" slab. Panel beside goes on top, pen marks show approximate shape although It will be much slimmer looking. Total thickness of the foam once all glued together will be 3", most of which will get cut off. Finished main beam thickness will be no thicker than 1 1/2". Refer to first drawing at top of this post for actual shape.
All the holes I drilled in the aluminum tabs were filled with epoxy after drilling down into balsa 1/8" deep through each hole. This forms a pattern of 1/8" epoxy knobs secured into the wood.
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3" styrofoam sandwich. Not glued together yet since I need to fill some cracks and spaces with epoxy first and attach the rear stays.
It would have been better if the outside panels were 1/2" thick instead of 1" so there would be less cutting and carving.
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Front part of frame trimmed closer to shape. Now to thin it down to 1 1/2" thick and round out the edges into peaked curves. Rear stays and their extra bracing are next to go on.
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Frame in jig after epoxying the rear stays on. It is all lined up along the green line on plywood. Note plumb bob hanging off front. A couple drops of crazy glue to the jig holds it all in place while epoxy cures. The wood screws are visible pinning the rear stays on. I used oversized holes and filled with epoxy for a little final adjustment. Upper and lower angle braces will be added to the rear stays next then filled with foam.
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Two views of the bracing of the rear stays, top one shows dual top and bottom bracing, second view shows small cross bracing between stays. All wood to wood connections have plywood wafers inside. Note carve outs in braces to wrap around tube, holes drilled in aluminum for epoxy.
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Rear stays with foam covering started.
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A couple of spare wheels and a set of forks just to check clearances and measurements. I need to trim out more for the tire clearance and lots of trimming and shaping.
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With the amount of sideways flex of the rear stays I decided to add something to strengthen. A 5/16" brass tube from a hobby shop proved to be quite strong for the weight. There are some small drill holes on the bottom of the tube for epoxy adhesion and is embedded below the top of the foam in a groove. Note bracket on inside of other rear stay for the coaster brake arm.
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The wheel is done and looking pretty sweet. 8 speed Nexus hub on a Mavic F219 rim with stainless steel spokes with a coaster brake. Total cost was $550 with a special order Alfine tap shifter. Its a bit heavier than I was hoping but when the dérailleurs, extra chain is factored in there isn't much difference. The hub comes with two sprockets and are easy to change. One is a 19 tooth and a 21 tooth. Range of sizes available is 16 tooth to 23 so it can be a high speed cruising 8 speed or a more fun "play in the dirt" range can be selected fairly easily. Of course the size of crank gear will determine the initial range. Recommended crank gear size is 36 to 42 tooth.
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A preview of the shape. A bit more tweaking in shape then the fibreglass starts.The use of small pieces of styrofoam makes for an uneven looking surface. It is much smoother than it looks. That line from the seat post to the bottom bracket is actually smooth and slightly curved. Once covered and painted the smooth lines will stand out.
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A sweet Sugino crank. 42 tooth is the upper limit of recommended chainring size.
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Thoughts on the Project
This little section could change fairly often as the build progresses.
I like the shape and design. The balsa core is amazingly strong and light. Styrofoam works nicely for filling and shaping but the epoxy did not. It does not bond real well to the styrofoam and makes sanding and shaping very difficult due to its toughness. Maybe a silicone would work better. I would try to use a lot less small pieces and take more time fitting them exact to minimize gaps. It should have been two large pieces per side. 1/2" thick foam would have been much easier to work with also. 1" was just too much to cut away. I actually feel that using solid balsa without the styrofoam would be a simpler and easier way to go. The weight would be slightly more than the styrofoam but a wood glue could be used and shaping would be much easier than with epoxy. Covering the aluminum tabs with balsa would be harder but better results in the long run. It would need more strengthening at the higher stress points with carbon fiber or whatever. I would still use the epoxy adhesive for the aluminum to wood connections.
The 1/2" x 1" balsa for the rear stays was not strong enough for sideways flexing and needed to be supported with the 5/16" brass tube as an afterthought. It would have been nice to incorporate a light weight metal beam into the rear stay design from the start. Perhaps a square tube or angle bar. The brass tube stiffened it up enough. The balsa part of the rear stays will support an amazing load straight down but too flexible sideways, perhaps another 1/2 x 1 in a "T" shape on top and bottom of each stay would solve some of that side flex giving a heavier look.
The method of mounting the scrounged aluminum parts to the balsa with aluminum tabs and drill holes seems to be very strong. The only way to improve the strength would be more drill holes and a metal screw into the balsa with lots of epoxy. More careful trimming of the tabs would have prevented a bit of shape change to avoid hitting metal.
I have tried sourcing carbon fibre and is difficult to find here and is extremely expensive. To provide strength in bonding the aluminum parts to the rest I will be using aluminum screen strips under the the fibreglass. I figure on the high stress points three layers of screen embedded in epoxy resin and then 3 layers of fibreglass in epoxy resin will add plenty of strength. Most of the side panels will be just fibreglass. I will use 1 minute epoxy adhesive to secure the screen down before applying the epoxy resin. I will need to use an old axle to secure the rear stays in exactly the right position while I apply the screen and fibreglass. The left side rear lug is a bit crooked so I will use the resin to hold it in a better position. A 6" piece of threaded 5/15" rod with flat washers and 4 nuts should have been the starting point while doing the final assembly of the stays to the main frame. The amount it is out of align will not be a concern after the resin. In gluing on the aluminum screen I have been trying different epoxies. One is a marine epoxy that dries quite hard and is sandable and dries white in colour. It has a 2 hour set time. The 5 minute epoxy is easier to work with until you try to sand it.

Major note of interest, epoxy resin eats styrofoam as does fibreglass resin. I really goofed on the first coat of resin. It needs to be painted first. I just laid the first panel of glass cloth on it cut to the shape of the whole one side then started brushing on the resin. By the time I had spread out the resin I could see small bubbles forming under the cloth. A few minutes later and there is major amounts of foam being eaten. I don't know if this will leave a space behind the cloth but if it does I will have to strip all the foam off the frame and start covering with balsa then reshape. I will update the status after the resin hardens and see what I end up with.
After the normal curing time for the resin I looked at it. The foam dissolving mixed in with some of the resin and is not hardening. It feels pretty well dry on the surface but is quite liquid underneath.
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This is after two hours. The resin did set up normally and the glass is hard but where the foam dissolved it sagged leaving no air bubbles. In places the sag is as much as a quarter inch deep. It will be possible to fill the low spots but at the cost of more weight. The other side will get painted with a latex before the glass is laid on it. It looks pretty bad but is savable. It will likely end up weighing as much as the aluminum frame by the time I get it looking right. This mistake will cost lots in terms of money, time and final weight.

I'm posting this boo-boo so that nobody else makes the same kind of mistake.

After some consideration I am going to strip the cloth and foam down to the balsa core and cover it in solid balsa then shape it the same then do the cloth and epoxy resin again. By using wood glue for the balsa it will be much easier to work with and shape and sand and will not require any prep before the epoxy resin and fibreglass cloth. By stripping off the styrofoam I will be able to fix that design flaw of the flex in the rear stays hopefully without the brass tubing and still keep the shape the same.
Update - The fibreglass and foam stripped off down to the balsa quite easily leaving a thin layer of epoxy adhesive which chipped off easily. It didn't stick to the styrofoam or the balsa very well. It adhered to the balsa good if it was sanded first with 60 grit so all the new balsa will get sanded down enough to give something to stick to. The balsa is going on very nicely and quite easy. The large flat ares of the sides are pretty well covered in 1/2" and the rear stays in 3/8". Most cutting is done with an Olfa knife or a small saw. The wood glue dries pretty slow compared to the 5 minute epoxy but it does bond very well and is easy to sand. Probably about another 8 hours of work with the balsa. It makes me wonder why I didn't build it from balsa the first time.
The brass tubes on the rear stays were very well adhered and would have caused more damage than it would be worth to remove them so I left them on and added balsa around them much the same way as with the foam only better fitting. Some final shaping this weekend then I'll post a pic of it before I start on the fibreglass.
One idea I came up with is to stain the wood and do a fake faux woodgrain finish. It would show quite nicely through the fibreglass cloth and epoxy resin. Balsa doesn't have any real grain since it is so fine and straight. A high contrast of colours in the faux finish would allow it to show up even better. I would finish it off with a silver and blue wedge stripe with the decals on the stripe. A few large knots and swirls in the grain maybe something like a light coloured walnut. If it didn't look right then I would just paint it all sliver with a blue wedge as originally planned. Elsewhere in this forum is a bunch of pics of some faux finishes I did on furniture. It would be nice to "advertise" that its a wood frame and show off the uniqueness of it.
One nice thing about stripping it down and building it back up with balsa is that I left the axle spacer on the rear lugs the whole time and it straightened out the crooked lugs. I will put the axle spacer back in before the fibreglass part starts and that will strengthen the stays even more and keep them straight.

Balsa pretty well complete. A bit more shaping left.
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Some light weight body filler putty has been applied to the ends of the balsa to smooth out the transition to the aluminum. Easy to sand and shape and little weight once dried. It will allow the fibreglass cloth to lay flat without any gaps behind. I have a large piece of cloth easily twice the length of the frame so I plan to fold the cloth then cut it to the shape of the frame and leave it connected at the steering tube so it wraps around at that spot. That will be for the final layer of cloth covering everything and leaving a smooth panel all over.
Finally got the first layer of fibreglass cloth on with one layer of resin. I did the cloth in one piece for both sides wrapped around the steering tube but I didn't allow fo the stretch of the cloth and it buckled up on the front of the tube so I didn't apply any resin there yet. So both sides are covered with only the inside of the rear stays left. The cloth wraps around and meets around the whole perimeter of the frame. That means I will have to use a 2" wide strip of cloth over the edges all the way around and blend in the edges later with sandpaper. Then a couple of coats of resin to smooth it all out to be block sanded before paint. I seriously considered the woodgrain idea but any more than one layer of cloth would be visible through the resin so the 2" strip would be visible. I could finish the resin then do the woodgrain on top but it wouldn't be as durable considering the different types of paint needed and the silver, blue, clearcoat and decals wouldn't adhere well enough. The original silver with blue accent stripe will be what it gets. Next photo when finished fibreglass.
Fibreglass is on with one more coat of resin to go. I have to block sand it down first. Having only played with it a couple of times in simple repairs my skills with fibreglass cloth are pretty slim so I have a lot of touch up to do. After it gets block sanded down close to level it will get a coat applied smooth then probably more block sanding and perhaps even some filler putty if needed before paint.

Fibreglass and resin finished. A bit rough in spots so some block sanding needed. A few drips etc. Regular "body work" from here, block sand, putty fill, block sand then primer, wet sand and finally paint next weekend for sure. Note cable buried under final coat. I completely forgot about it until before the last coat so I had to router a groove through the fibreglass then cover it in putty before that last coat of resin. For a giggle note the blue lines up over the top. I run the cable the wrong way cause it was upside down. Glad I noticed it before the router.
Its block sanding down pretty good. A bit of a grunt but it coming out nice and level and smooth after removing about 1/16" of resin.
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As what is becoming a common theme for this project I am now another day behind. In my haste to get the balsa done I did not fit crank and wheel with chain to check for clearances before fibreglassing. Damn. There was considerable chain rub in a few spots so had to cut away fair amounts of fibreglass and balsa to make clearance. A slight change in shape but not much with a relief cutout around the crank. I also had to reroute the cable housing leaving more of it exposed also leaving a cable housing wide groove across a wide section which had to be filled. So after a burger and shake I'll get back to it and hopefully get it in primer tonight.
I also found out that the Sugino crank will require a 1/8" chain to be compatible with the Shimano sprocket on the wheel and the Messenger 42 tooth ring which is for a 1/8" chain and Shimano is 3/32".

Finally in primer. A scratch filler sandable thick coat primer that does wonders for small imperfections. Still a few minor spots to touch up tonight then paint tomorrow.
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Cablehousing is held in place with a metal staple at each end. Staple is krazy glued into two small holes drilled on either side of housing. This will prevent housing from pulling out, ripping resin, paint etc.
First coat of silver went on and it looked like crap. It brought out every little flaw in the primer and below. So its back to fill and block sand. If I want the paint to look good it will require some more work and time. Add another week to the build.

Beautiful in Silver. A few minor flaws here and there but I'm tired of mucking with putty and primer. That is 3 coats of Chev Bright Silver by Duplicolor.
Decals and blue stripe tomorrow them lots of clearcoat lacquer. Assembly on Sunday.
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A note about the vertical dropouts. I stayed with those and when I mounted the wheel and measured and cut the chain it worked out perfectly with no adjustment needed. I bought a half link in case I needed it but didn't. Pure luck there.

Thoughts for the Future
Due to my age I am considering going to an electric assist system in a couple of years to take a bit of stress off the legs and make longer distances easier. At that time I will think about building another frame incorporating battery storage into it. I hate the present look of electrics with a rear carrier or battery pack strapped on somewhere so want to hide them inside the frame. I would likely go with a front wheel electric.
To build the frame I would go much the same route as this one minus the styrofoam diversion. The balsa works very nicely and the fibreglass and epoxy resin work quite well so those materials would be used next time. I would start with the balsa core designing for strength then cover it. I ended up with a larger looking frame than I wanted due to adding some simple streamlining around the bottom end so would want the next to be slimmer looking.

The decal sheet. The main decals could have been a bit smaller and the Nexus 8 decals could have been a bit bigger.
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Decals and clearcoat finished. I think the main decals could have been a bit smaller.
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Closeup showing metallic maroon stripe added as a late idea.
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Time to assemble.

Yeehaa!!!
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After 7 months of planning and building it is finally done. The frame feels amazingly stiff with no flex and feels real good. The Nexus 8 speed works very nice and makes shifting smooth and quiet.
Was it worth all the time, money and work? I will post an addition to this post in a week or so with my thoughts on it all after some seat time.
But today I spend enjoying this new bike. Time for a ride.

UPDATE
After a one hour ride I must say I am pleased. It rides very smooth and tracks straight. I kind of grimaced going over the first curb but it handled it real nice. It was nice to bounce off a curb and not hear the chain rattling. There isn't much flex if any and feels very solid. I rode it pretty hard too.
The Nexus 8 speed seems to be pretty good. I find the overall gearing a bit low maybe so some seat time will tell if a sprocket swap is in order.
A thought on swapping sprockets, due to having no adjustment for tightening chain I have to make the chain length exact. When I swap to a smaller sprocket the chain will be too long and loose. I will simply pick up another chain and make it fit with the small sprocket and have matching chain and sprocket sets. Because the dropouts are vertical and no chain running through the rear stays the chain doesn't need to be split to remove it. I can drop the back wheel and swap the sprocket and chain in a couple of minutes.
A few minor adjustments like handlebars and the front brake is squealing a bit and bring the tire pressure up to around 80 psi, 40 psi was ok for testing. Tomorrow it gets the real test to work and back, 30 minutes each way.
After a return trip to work, the bike performed amazingly well. The Nexus 8 is real nice to use. There is some gear noise inside that gets amplified by the balsawood and makes it noticeable but still quieter than the dérailleur. Energy use is greatly reduced compared to the old Crank Monster, I found my legs and lungs were much happier. The Nexus 8 gearing ratios are not evenly spaced. I read some complaints about the ratios on forums and blogs but I find them well matched. The 1st and 2nd are like on the smallest chainring of a three gear crank. 7th and 8th are like on the biggest chainring and 3rd to 6th are like on the middle ring and those middle gears are spaced fairly close which allows choosing the right gear for your ideal pedal cadence in the average cruising gears. With the 21 tooth sprocket and the 42 tooth chainring I have gearing ranging from the lowest to about the 24th or 25th of the old 27 speed.
The old Crank Monster donated a couple of parts to its successor. The forks and front wheel, Forks are quite soft and not downhill type, good for commuting, handlebar stem and seat and seat post.
I found many things wrong with the old beast. Bottom bracket bearings were just about non-existent, the rear shock mounting plates have oval shaped holes and quite sloppy, pivot point of swing arm bushings sloppy. Front dérailleur not working at all, rusted solid, in fact shifter seized last year and cable was removed all due to lack of use. Rear wheel bearings rough and noisy, derailleur sloppy and worn out, V brake arm bushings worn and sloppy, peddle bearings grinding and sloppy and rear shifter getting sloppy. Lots worn out but thats after 8 years of commuting all year long. It served me well. I put $1400 into $500 bike and this new one I have $1300 into it. Hopefully I can get at least a few years out of it.

After a couple of days riding I found a few small cracks. Nothing real serious but cracks none the less. One is around the brake arm bracket and one on each rear stay right where the fibreglass meets the aluminum of the dropout. After noticing these I rode it the rest of the way home real hard and bouncing over curbs like my normal riding style and it didn't get any worse. I dribbled some Krazy glue into the cracks to keep them from chipping the paint. If they do not get any worse then I will just sand down the sharp edges of the cracks and mask off and throw some silver paint at it. It is possible there was some stress there from when the fibreglass was applied and it shrinks a bit. It doesn't seem to affect the structural strength since all the strength was built into the core and not dependent on the fibreglass. I'll be keeping a close eye on those cracks. It still rides good and feels solid. If the cracks do get worse then I will drill from the back of the dropout forward into the stay about 6" and epoxy in a threaded rod probably 5/16" or 3/8".
The next frame will have some improvements in that area.

Crank Monster E ?
Commuting for a couple of weeks now and the bike is still amazing. No further cracks or worsening cracks so they will get touched up. There is a noticeable difference in efficiency. The only problem I have is my own physical limitations. My back has been bothering me for the last week and with a pinched nerve my legs always feel like I just finished a 20 mile ride. Even with the noticeable improvement in efficiency I have been struggling. I'm hoping the back problem heals itself quickly and gets me back to enjoying my ride. But it made me think about the future. I am peeking at 60 years so I am now planning to start the electric assist frame fairly soon. Designing is going to start right away. Sort of a "winter" project if it takes that long. With what I learned building the balsa frame it will have all the improvements I've learned and wanted. It will be a much sleeker and smaller looking frame with battery storage built in. I plan on going with a front wheel motor so that I can keep the Nexus 8 speed for normal biking and click on the motor when I need it. Kits are available with a complete front wheel and all that goes with it ranging from a few hundred up to over $2500. There are also choices like full electric, peddle assisted and combinations of those two. I will go with a system that is a combo, peddle mostly with electric assist for hills and against the wind. I don't need a long range and a longer range means more batteries and more weight. I would like the bike to be still useful without using the electric and not weigh a ton. The debate on which battery is best is still ongoing. The main choices are sealed lead acid and lithium and NIMH in 36 and 48 volt and 9 Ah to 15 Ah. 8 to 12 lbs. is pretty normal. I will likely end up with 36 volt and 9 Ah which is still enough to get me to work even with lots of "assist". Further research is needed before I make a decision. The lead acids are just plain heavy and large. A 36 V 9 Ah lead acid pack weighs 17 lbs. A Lithium pack of the same rating weighs 7.7 lbs. Pricing is noticeably different as well. $190 for the lead acid and $390 for lithium. NIMH batteries are the tops right now and a 36 V 9 Ah pack is $450 and up. NIMH and Lithium are pretty well equal in size and weights. So you could say $200 extra to weigh 10 lbs less. Size is 8" x 6 x 3.75 for lead acid made from 3 cells and the lithium is made from D size probably and 30 cells. The lithium would be easier to hide in the frame by removing them from the pack and wiring them all together allowing for a variety of shapes to suit the frame dimensions and keeping them near the bottom for the lower center of gravity. There is also the electronic controller box that is near as big as the batteries and a charger built in to consider. The control box also needs some form of cooling and allowances for all the wiring between controller and batteries and to motor and throttle / switch on handlebars. The cable housing for the Nexus will be buried along with the wiring in the first stages of the frame build. A waterproof Molex plugin on the frame with a flexible strain relief on the cable for the electrical seems the most sensible way to go.
For the aluminum parts I think I will cut up the original Crank Monster but make a few changes to how its cut. The rear dropout tabs will be twice as long at least to strengthen the back end more and the other parts will have longer tabs as well. I am looking into some type of hard wood for a couple of pieces of the core just for added strength even though the all balsa is amazingly strong. The seat post to bottom bracket and the bottom rails of the rear stays. The frame will have to be tough because at 20 mph on a bumpy bike path I do not want the thing breaking up and being the crazy old-school nut that I am, I am sure that eventually the batteries will be upgraded to 48 volt (or more) and close to 30 mph (or more).
Much planning and research to do.
The Crank Monster E is definitely in the works so a new post will be started for it.


Disclaimer: I fully support anyone trying a build like this but I am not responsible for for anything built using these methods.
That said, please feel free to use whatever ideas, drawings, photos in building your own.
I welcome any thoughts or questions on this bike.
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Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Fri Oct 22, 2010 9:26 pm

The Amazing Forkless "Phantom Bike" by Olli Erkkila
Image
Single fork might be more like it.
http://www.treehugger.com/files/2010/10 ... php?ref=nf
Pictures and video here
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Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Wed Nov 10, 2010 4:10 am

CRANK MONSTER II DONOR FRAME
THE DONOR FRAME AND THE CUT PATTERN.
Image

HEADSET CUT AND DRILLED. I CUT THE TOP AND BOTTOM OFF THE OVAL TUBE AND FLATTENED OUT THE SIDES TO 1" APART FOR THE BALSA CORE.
SLIGHTLY DIFFERENT FROM THE CUT LINES ABOVE.
DRILL HOLES ARE FOR EPOXY RESIN GIVING A BIT MORE BONDING STRENGTH.
SILVER POWDERCOATING STILL TO BE REMOVED.
Image

REAR LUGS
TABS NARROWED TO FIT 1/2"X 1" REAR STAY BALSA
THESE LUGS MAY NOT BE USED DUE TO THE NEED OF HORIZONTAL DROPOUTS UNLESS A CHAIN TENSIONER IS USED.
Image

BOTTOM BRACKET AND SEAT TUBE
OPEN TUBE ON BOTTOM BRACKET IS FOR FRONT DERAILLEUR MOUNT. FRONT DERAILLEUR WILL NOT BE NEEDED WITH 8 SPEED INTERNAL HUB.
1x1 BALSA WILL CONNECT SEAT TUBE AND BOTTOM BRACKET INSERTED INTO TUBING.
Image

REAR BRAKES
ONE CUT TO FIT 1/2X1. OTHER WILL BE THE SAME.
CABLE LUGS WILL BE REMOVED
THESE WILL NOT BE USED SINCE THE 8 SPEED INTERNAL HUB HAS COASTER BRAKES.
Image

Yes I just cut up a near new aluminum frame. If you know the "Next" brand name and where it comes from (Walmart in Canada) then its obvious it is not an expensive frame. It was a cheapie with a broken wheel and a few missing parts before I found it. Should you wondewr about a serial number for the frame, I took the number off the donar frame and run it through the police and it is not listed as stolen so I will use that number by making a metal S/N plate embedded in the epoxy resin. It will be in the normal place on the bottom bracket. I could use any thing I wanted on the plate but a S/N that looks real is good enough.
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Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Sat Jun 04, 2011 8:36 pm

The Bike Shop

Summer Hours: Mon, Tues, Wed: 10-7, Thurs & Fri: 10-9, Sat: 10-6, Sun: 11-5

801 11 Avenue SW
Calgary, AB T2R 0E6
Phone: 403-264-0735 or 1-800-665-7433
Fax: 403-265-1226


Having a reliable good bike shop is always important. I deal with this store because they have been around a long time with a great reputation and some of the staff have been there as long.
I use them mostly for getting parts but gladly gave them the 8 speed Nexus wheel build for Crank Monster II. Shane in the service dept is one of the best mechanics around.
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Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Sat Jun 18, 2011 7:26 pm

Proper Bike Fit Can Prevent Pain and Injury
How to adjust your bike fit for pain-free cycling

http://sportsmedicine.about.com/cs/sport/a/bikefit.htm

Whether you are riding to the corner store or across the country, you should be comfortable on your bike. If you have neck, back, or knee pain, saddle sores, or hand or foot numbness, your bicycle probably doesn't fit you properly. Good bike fit can also improve your pedaling efficiency and aerodynamics and actually make you faster. Here are the basic bike-fitting principles:

Adjusting the Saddle
Your bike seat should be level to support your full body weight and allow you to move around on the seat when necessary. Too much upward tilt can result in pressure points. Too much downward tilt can make you slide forward while riding and put extra pressure on your arms, hands and knees, which can lead to injury.

To adjust the seat height, wear your biking shoes and riding shorts and place your heels on the pedals. As you pedal backwards, your knees should fully extend in the down position. If your hips rock side to side the seat is too high. Now when you move your foot into the proper pedaling position, with the balls of your feet over the pedal, you'll have a slight bend in your knees.

You can also adjust the seat forward and backward (fore and aft position). With your feet on the pedals so the crank arms are parallel with the ground, the proper position will put your forward knee directly over the pedal axle. Dropping a plumb line from the patellar tendon makes this adjustment a bit easier to see.

Handlebar Adjustment
If the handlebars are too high, too low, too close, or too far away, you may have neck, shoulder, back, and hand pain. A proper reach allows you to comfortably use all the positions on the handlebars and to comfortably bend your elbows while riding. There are other, more advanced adjustments you can make, such as changing the handlebar width or height.

Because your body is asymmetric (one leg or arm may be slightly longer or shorter than the other) an ideal bike fit is often a matter of trial and error. The slightest imbalance can lead to pain. Here are some common complaints and possible solutions.

Knee pain is usually associated with a seat position that is too high or low or far forward or back. Improper bike shoe or cleat position can also cause knee pain.

A seat that is too high will cause pain in the back of the knee.
A seat too high will also cause your hips to rock side to side, which may cause discomfort.
A seat that is too low or too far forward may cause pain in the front of the knee.
Improper foot position on the pedal (or improper cleat alignment) can cause pain on the inside or outside of your knees.

Individual anatomy may also result in knee pain. Cyclists with slight differences in leg length may have knee pain because the seat height is only adjusted for one side. Shoe inserts or orthotics can help correct this problem.

Another cause of knee pain is using too high a gear. Try to use a gear that allows you to pedal quickly, from 70 to 100 strokes per minute.

Neck pain is another common cycling complaint, and is usually the result of riding a bike that is too long or having handlebars that are too low. Tight hamstring and hip flexor muscles can also cause neck pain by forcing your spine to round or arch, and your neck to hyperextend.

Foot pain or numbness is often the result of wearing soft-soled shoes. Special shoes designed for cycling have stiff soles that distribute pressure evenly over the pedal. This also helps you pedal more efficiently. Foot pain can also be caused by using too high a gear, which results in more pressure where the foot meets the pedal.

Hand pain or numbness can be prevented by wearing padded cycling gloves that provide cushioning. You should ride with your elbows slightly bent, not straight or locked. Bent elbows will act as shock absorbers and help absorb the bumps in the road. Changing hand positions on the handlebars can also reduce pressure and pain.

Saddle sores: Finding a bike seat that fits you well is imperative. Also see: Choosing and Adjusting Your Saddle.

There are dozens of bike saddles designed for every rider and riding style. Saddles come in a variety of materials from gel to leather. There are women-specific saddles that are shorter and wider to accommodate a woman's wider pelvis. Others have a center cutout to relieve pressure on soft tissues. You should try several to find one that fits you well.

Your cycling clothing can also cause saddle sores. Cyclists typically wear shorts made without seams — and no underwear — to eliminate sources of chafing and pressure points. Cycling shorts also have padded liners that provide more comfort than street clothes.
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Hot Electrics

Postby zappdog » Sat Jul 23, 2011 1:16 am

Image

http://www.yankodesign.com/2011/07/19/e ... brid-bike/
INgSOC
Yanko Design

Stop panting. Its only a concept. But what a concept. Hybrid human - electric powered.
3 modes, electric, peddle assisted and peddle battery charge.


Image
http://picycle.com/comparepicycles/
Check out their Kenny Roberts version. 45 mph
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Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Fri Aug 12, 2011 3:38 am

2 Cyclists die in Montreal this Week
Image

I started my day today by learning that a 17 year old cyclist involved in a collision yesterday didn’t survive the night. He was the second cyclist to die in Montreal this week. The first one was a 56 year old man who got crushed by a cement truck turning right while he was trying to go straight on his green light. The case of the young teen is a debate on who went through a red light. Whatever the reasons or the blame to lay, 2 people are needlessly dead.

Now this prompted a big debate over the local media about cyclists being chronic scofflaws or drivers being homicidal maniacs. The numbers are in about this. Of the 800 incidents involving bike collisions last year, the Montreal Police reports that responsibility is split 50/50 between cyclists and drivers. I admit that I see bikes blowing red lights and stop signs. What we need for that is more regular enforcement. Cops on bicycles should do regular operations to enforce traffic laws for cyclist as their counterparts in cars do with motorists. The occasional spot checks don’t work. Cyclists here know that getting a traffic ticket while biking are in the same range of odds as winning something at the lottery.

The biggest concern in my opinion however, are the riders who go out there and ride unaware. Unaware of the risks and dangers. Unaware of the consequences of ignoring basic safety issues. Unaware of the fact that they are invisible to most drivers and since a lot of drivers are also out there unaware, collisions are bound to happen. Riding a bike with your brain switched off is suicide.

Here are some tips that will keep you safe and hopefully alive out there:

Be aware

Make sure all your senses are available for the task. No ear plugs, both hands on the handlebars and your eyes open for traffic next to you, behind you, in front of you and beyond. Anticipate so you don’t get caught reacting at the last moment.

Assume nothing

Prepare for the worst scenario every time. Don’t assume that the door won’t open, that the car driver is going to go straight, or stop or go or turn or see you or anything else for that matter. Hoping for good things to happen instead might get you killed. I did that mistake only once and ended up flying in the air launched from a car windshield. I assumed that the driver saw me while I was crossing the street on foot, on a green light and he was about to turn right in my path. Luckily I survived unharmed, you might not.

Respect traffic laws

Riding on sidewalks with pedestrians present is dangerous, get off your bike and walk. Pedestrians should get the respect that you expect from drivers on the road. Stop and wait at red lights. I know that it’s a bummer when there is no traffic but leaving on a red while cars are waiting only perpetuates the myth that all cyclists are bums. If we want respect from drivers, we need to share at least a little of their time wasting frustrations like this one. Slow down at stop signs at the very least, proceed through only if there is no traffic present whatsoever. Don’t ride against traffic. The reasoning that it’s less dangerous to have traffic in front of you being safer is absolutely stupid. Drivers get confused when they see you and this could actually cause you harm. If you are paranoid about cars behind you, get a mirror or two. They are cheap and available everywhere in all sizes.

Be visible at night

Forget riding in the dark with only reflectors, they are unidirectional and a driver might see you only when it is too late. Less than $10 will get you a blinker for the front and back of your bike with enough power to last an entire season. Want to stand out big time? Get one of those lime yellow reflective vest, you will never go unnoticed.

Wear a helmet

I’ll mention this sticker I saw on a courier’s helmet: “I wear a helmet because of the way you drive.”. You just never know when your head will smack the pavement. It is proven that helmets reduce the risk of major head trauma by 70 to 80 percent. Use your brain and put a lid on it.

Physics, it’s the law!

And it’s always right. That should be your prime concern when riding. A 3000 pound car will always win against your flesh and bones. This law prevails over any traffic law when riding. Yeah you may have had the right of way according to the traffic code but if you are 6 feet under pushing daisies you won’t really care about the slap on the wrist that driver gets.

After reading all this you might wonder if I ride like a paranoid maniac all the time. No I don’t. Becoming aware is like anything else, you get used to it and it becomes second nature after a while.

If you wish to keep your head in the sand and still ride with an attitude that it won’t happen to you, here’s another story that happened this week as well: A man turned himself in yesterday 5 years after hitting and killing a cyclist. He hit a 43 year old Father of 2. The driver took the time to unjam the bike from under is truck one kilometre away from the collision and tossed it in a field before he drove off. He didn’t bother calling 911 to get help to his victim which he left to die by the side of the road. I’m not saying that every driver is out to kill you but if you ride as if they are, you’ll have an edge and have a much better chance of avoiding a collision.

Hopefully this post motivated by this sad tragedy might prevent someone, somewhere from getting hurt bad or dead.
To both families, my heart and sympathies go out to you.

Ride safe and ride free.

Gerry

By
Gerry Lauzon
How To Fix Bikes.ca
http://www.howtofixbikes.ca/2011/08/2-cyclists-die-in-montreal-this-week.html
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Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Thu Aug 18, 2011 3:37 am

Bike tools
Image

After many years of using the very cheapest of bike tools I suddenly found myself needing some better quality tools for my job of fitness equipment technician.
The pedal wrench shown is something I was a bit dubious about especially for the cost of it. My regular wrenches were too thick so I needed to have something and have found this one makes removing peddles much easier. The best tip I've had yet on removing stuck on peddles is to align the wrench on the peddle in an angle that allows a sharp blow with a dead blow hammer. Hold the wrench in one hand and hit the back of the wrench with the hammer. While working on an exercise bike I realized I had left the peddle wrench in the car and tried for quite a while with the tools I had on hand. I finally went and got the wrench and it loosened the peddle with one good hit of the hammer.
The crank puller is another example. This one has bearings on the end that contacts the bottom bracket axle and this makes crank arm removal very easy. My old ones did not have bearings and sometimes galled up the end of the threads.
The chain tool is another. The ones I have had for years worked if you were real careful. This one is just a step up from what I had but what a difference in using it.
For your own piece of mind and saved knuckles, buy the better quality bike tools. Walmart is not the place to buy bike tools. Go to a bike shop and ask them what they use and recommend and take their advice. You will not regret using better tools.
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Re: MOSTLY MOUNTAIN BIKES

Postby zappdog » Mon Sep 05, 2011 8:10 pm

Crank Monster E

Design Notes
Commuting for a couple of weeks now and the Crank Monster II is still amazing. No further cracks or worsening cracks so they will get touched up. There is a noticeable difference in efficiency. It is a much better bike than expected and probably the stiffest frame I have ridden. The only problem I have is my own physical limitations. My back has been bothering me for the last week and with a pinched nerve my legs always feel like I just finished a 20 mile ride. Even with the noticeable improvement in efficiency I have been struggling. I'm hoping the back problem heals itself quickly and gets me back to enjoying my ride. But it made me think about the future. I am peeking at 60 years so I am now planning to start the electric assist frame fairly soon. Designing is getting started right away. Sort of a "winter" project if it takes that long. With what I learned building the balsa frame it will have all the improvements I've learned and wanted. It will be a much sleeker and smaller looking frame with battery storage built in. I plan on going with a front wheel motor so that I can keep the Nexus 8 speed for normal biking and click on the motor when I need it. Kits are available with a complete front wheel and all that goes with it ranging from a few hundred up to over $2500. There are also choices like full electric, peddle assisted and combinations of those two. I will go with a system that is a combo, peddle mostly with electric assist for hills and against the wind. I don't need a long range and a longer range means more batteries and more weight. I would like the bike to be still useful without using the electric and not weigh a ton.
The debate on which battery is best is still ongoing. The main choices are sealed lead acid and lithium and NIMH in 36 and 48 volt and 9 Ah to 15 Ah. 8 to 24 lbs. is pretty normal. I will likely end up with 36 volt and 9 Ah which is still enough to get me to work even with lots of "assist". Further research is needed before I make a decision. The lead acids are just plain heavy and large. A 36 V 9 Ah lead acid pack weighs 17 to 24 lbs. A Lithium pack of the same rating weighs 3 lbs. Pricing is noticeably different as well. $190 for the lead acid and $390 for lithium. NIMH batteries are the tops right now and a 36 V 9 Ah pack is $450 and up and weigh 10 lbs. NIMH and Lithium are equal in size. So you could say $200 extra to weigh 10 lbs less. Size is 8" x 6 x 3.75 for lead acid made from 3 cells and the lithium is made from D size probably and 30 cells. The lithium would be easier to hide in the frame by removing them from the pack and wiring them all together allowing for a variety of shapes to suit the frame dimensions and keeping them near the bottom for the lower center of gravity. There is also the electronic controller box that is near as big as the batteries and a charger built in to consider. The control box and batteries also need some form of cooling and allowances for all the wiring between controller and batteries and to motor and throttle / switch on handlebars. The cable housing for the Nexus will be buried along with the wiring in the first stages of the frame build. A waterproof Molex plugin on the frame with a flexible strain relief on the cable for the electrical seems the most sensible way to go.
For the aluminum parts I think I will cut up the original Crank Monster but make a few changes to how its cut. It seems like a fitting end to an old friend. The rear dropout tabs will be twice as long at least to strengthen the back end more and the other parts will have longer tabs as well. I am looking into some type of hard wood for a couple of pieces of the core just for added strength even though the all balsa is amazingly strong. The seat post to bottom bracket and the bottom rails of the rear stays. The frame will have to be tough because at 20 mph on a bumpy bike path I do not want the thing breaking up and being the crazy old-school nut that I am, I am sure that eventually the batteries will be upgraded to 48 volt (or more) and close to 30 mph (or more).
The frame is going to be mostly balsa with a few pieces of a hardwood buried in the core for added strength and covered with fibreglass and epoxy resin. There are the batteries, controller, charger and cables to be hidden with the ability to get at any of those components. A removable panel or door. This drawing is an old one from planning the Crank Monster II. One of the discarded drawings. This is only a direction to go. The opening will likely be square or rectangle and a somewhat different overall shape.
Image
It has a cutout suitable for a 2 panel cover. The compartment would need to be bigger than that or a larger compartment with a smaller door but it gives me a possible direction. The batteries will have to be mounted lower in the frame than that shows to keep the center of gravity lower. Passive or fan forced cooling will have to be designed in. A plugin for all the wires from the front of the frame to the forks and a plugin for charging. The frame will be a bit thicker in some areas than the drawing and shaped more like the Crank Monster II only slimmer with all the same angles and measurements. I will use the previously marked out plywood for it.
A keyed lock will turn power on and off for safety and security reasons and be mounted on the cover panel and also act to unlock the cover. A simple heavy gauge leaf switch capable of 30 amps and a small cabinet lock that normally turns 90 degrees modified to turn further. A simple drawing shows how it will work. Key removable only in Off.
Image

Total cost for a complete electric system is going to be getting close to $1000. Buyer beware when looking for a system. I found one with a reasonable price and in western Canada so shipping should not be too bad. Complete kit was $750 but shipping was $890. It turns out their shipping comes directly from the factory in China. Same thing with just a motor. $122 for the motor but $360 for shipping. Buying from the US the shipping costs for a complete kit are about $80. I checked out a local shop that specializes in electric bikes and their kits are from $2200 and up. NiMH batteriy pack are $590. Maybe they are getting them shipped from China.
Batteries are the hardest to figure out. I expect to be going with Lithium or NiMH if I can find them wholesale. I will be building my own pack so that it can fit where I want it. The main choices are "D" cells @ 1.2 volt and 10000 mAh times 30 cells ($10 to 15 each) or "AA" size @ 1.2 v and 2300 mAh times 90 cells ($4 to 6 each). "C" size cells could also be used, 1.2 v @ 5000 mAh times 60 cells. This is the number of cells needed to make up the required 36 Volt @ 9 or 10 Ah. Adding more cells in series means more voltage and faster top speed. Adding more cells in parallel means more amperage and more distance. Due to the weights of batteries I am going to try to source them locally to save on shipping. If "AA" are used a case of 100 will likely be the best. If NiMH are used a battery management system needs to be included. They are sensitive to charging rates and balanced cells. There are many more choices in Lithium than NiMH and easier to find and easier to charge and manage.
The cells to make up the 36 v will take up quite a bit of room. The frame will need to be fairly thick from the seat post line forward. I laid out what 30 "D" cells would look like laying flat and it it 13" x 9" x 1.5" . Standing them on end gives a pack of 14" x 4" x 2.5". Laying them flat will take up too much room so one pack or 2 or 3 smaller ones standing up. I haven't tried to figure out "AA" size but it would likely be around the same dimensions. I would rather go with the "D" size simply because replacing any cells later would be easier if packaged as a 30 cell pack. With "AA" and 90 cells finding and replacing a dead cell would be harder and having a cell go bad is more likely having 3 times the number of cells. A bad cell will leave you in the same spot either way, peddling. Prices look like around 300 to 400 for them, I could go with a premade battery pack for a bit more but I might end up cutting it open to arrange the cells in a different shape so I might as well start with individual cells and build my own pack(s).
Motors are another area to research carefully. Two main types are geared and direct drive. Costs are equal. Sizes, ratings and weights are not. A direct drive motor will be 14 to 20 lbs and close to twice the diameter of a geared. Geared 7 to 10 lbs. Direct drive are higher wattage motors meaning a bit more speed and higher battery drain. Direct drive motors have no moving parts to wear other than bearings, the geared motors use plastic planetary gears and some have been known to wear out in a year or two. If geared then be sure to get an extra set of gears just in case they are "discontinued" later. At 600 watt and higher going direct drive pretty well necessitates more batteries. Geared are 250 watt and up with 350 watt most common. The gearing is what allows the lower wattage motors to near equal the direct drives in performance. With the extra weight for direct drive I would not want to be peddling it much and have to depend on the electric more. So the reason for going with the 350 watt geared, I want to peddle mostly with assist when needed.
Front wheel and rear wheel motors call for different considerations. Front wheel is simpler with only the wiring from the frame to the forks, apparently less traction under acceleration in slippery conditions. Rear wheel involves the gearing for peddling the bike which is limited to single sprocket or a dérailleur and cassette. Since I just went internal hub and love it, the front wheel motor is my choice. The internal 7 and 8 speed hubs are common on many complete front wheel electric bikes.
Due to the costs involved this will likely be a winter long project.
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