Cannonballs Abbynormal 3Speed.

[cannonball2]

Got the "concentric" trans roughed out. Was an easy few hours work( broke out the metal cutting band saw is why). It has worked out so far exactly as I have envisioned. Fits well and the chain lines are reasonable. Was worried about the chain to the rear wheel being offset more than I wanted but looks ok. Wont really know until the sprocket is installed on the wheel. Thats the only real concern at this point. Will have to trim the engines case a bit to allow the chain a straight shot. But that's not a biggie. Will still have plenty of case/thread left to mount the clutch cover.
Running an MTB wheel to get some offset for clearance so the wheel is displaced a bit to the right. I can live with it. The only other trans specific hurtle is to mount the shift cable/handle and that is pretty straight forward.
Of course the bike has to be built as well.

 

[silverbear]

I love it!
SB

 

[Intrepid Wheelwoman]

Shiny

It's looking good so far CB.

 

[Ludwig II]

It's all very nice, but it's not as "you" as a belt driver.

 

[bowljoman]

I f'ing LOVE IT!

 

[silverbear]

I was wondering what kind of driven sprocket you have in mind? A kit rag joint? I'm thinking that a clam shell type of hub adapter (mine are old Manic Mechanic adapters) would give you some lateral adjustment that might make alignment easier. Whatever you do, I'm sure you'll find a way to make it work. Can't wait to see this in action...
SB

 

[cannonball2]

Thanks Yall!

L2, Im a man for all season so to speak. I will make it go anyway I can. Have been thinking I haven't ventured into hydraulics yet.

Thanks Bowljoman! This is all inspired from your builds AND your encouragement to fly in the face of the naysayers!

SB, initially I will run a rag joint. I hated these things at first but with some careful installation they run pretty true and I haven't broken any 14ga spokes so far. Im sure running a stock engine helps. Most of the clam shell adapters are for the coaster sized hubs. Some where I did see a smaller one for the free wheel hubs like I am running, but don't remember where. Im thinking the offset of the wheel plus the offset of the sprocket will get me where I need to be. I run BMX bike chains so the clearance is maximized.
I have a question for you. You have a common SA 3speed hub right? Next time its convenient lock the non sprocket side axle in a vice. Mark the hub and a tooth on the sprocket and turn the hub and count how many ratios you get. I would appreciate it. This will determine if all the coaster type 3spds will only do two ratios running backwards.

Im anxious to get this thing up and running, but tax time is coming and Uncle Sam may get the extra $$ for my MB addiction. Im short several basic parts for the engine install. I will rob what I can though from the less active members of the MB clan in the garage. Maybe I can piece it all together for a test run. In the meantime will finalize the drive system.

 

[silverbear]

CB2,
It will be awhile before I can check the hubs as I'm house sitting for neighbors while they are on vacation someplace warm. Then I need to dig out the 3 speed SA hubs. I know at least one of them is of the coaster brake type and the others are free wheel type & also a 2 speed Bendix. The vice is bolted to a picnic table outside under snow, but as soon as it warms up a bit I'll unbury it and see what I can find out.
SB

 

[Ludwig II]

Hydraulics, fine, at bicycle speeds the motor units are probably well within their rev range.

Have you considered compressed air? Pneumatic tool motors can be big enough to dish out considerable torque. You'd need to find a small and light compressor though.

I wonder if there is an engine with enough exhaust gas to run a turbine or positive displacement motor from it. 2 strokes normally aren't any good for supercharging, but what if one were used as a rapid response gas generator, with an extraction type exhaust instead of an expansion chamber

Of course, I wouldn't tempt you with the thought of a pair of 90 degee out of phase oscillating drives from a reduction gear to a back wheel, no, I wouldn't dream of mentioning that to you.

 

[Ludwig II]

OK, I confess, I am evil.

Look at this: http://en.wikipedia.org/wiki/Fireless_locomotive

 

[cannonball2]

Don't worry about when SB. Am just curious. If the common 3spd hub could be used it would certainly be cheap enough.


L2, you are right! I haven't tried steam! Have to do that before going fireless. A natural progression you know.

 

[LandSpeedRecord]

I see how you set it up Cannonball. That is a great set up and I could really benefit from that hub if it can hold up. That is definitely the best way to shift I have seen yet for a motorized bicycle. I keep thinking I need some sort of transmission and that is the first I have seen that makes sense. I am going to do some research on how much it can handle and probably go that way at least for the street. My compliments to the idea and build you have there.

 

[cannonball2]

Thanks LSR! Im optimistic but its not proven yet. I don't have doubts about the hub handling the power at least for a CG as they have limited torque as compared to a 4stroke. The internals are well sized to handle the loads a fixie imposes in both directions, and like standing and pedaling up hills. Many 3speed hubs warn not to stand and pedal. This will allow the bike to pedal start, though a pull start could be used too. Another forum member Brown was also on a similar track with the SX3 hub but I believe was going to run the hub in the rear wheel which once built is an even cleaner way to do it. Problem was a bike with pedals needed a freewheel to be added in some way to the non sprocket side of the hub. There is not enough material to simply cut the threads, so maybe adapting a clamshell adapter in some way would do.

I wanted to do it in a way that kept the project out of the machine shop for the DIY builder, so far I have avoided that. The shifter hook up should be simple enough with a bracket mounted on one of the engine side cover bolts for a cable anchor. The supplied bar end shifter may be a little awkward, or may not, probably depends on the handlebars shape.

Heres a link Brown posted in the other thread showing the hubs breakdown.
Look at the size of the driver, sliding clutch splines and the face of it that achieves lock up in high, pretty stout, at least compared to other hubs. Incidentally my build is on a fixie frame similar to yours. https://www.youtube.com/watch?v=AJmUds2YQ74

 

[cannonball2]

For got to add another advantage is the there is no freewheeling with this hub set up like on other shifter bikes. No more snatching the freewheel when matching speeds and coasting down hills working the brakes. This one provides engine braking while off the throttle.

 

[cannonball2]

Ok got the drive basically finished. The chain lines are perfect! Its a close fit to the rear wheel, but there is more than adequate clearance. The pedal chain is a bit loose when the drive chains are adjusted, so will just add a small idler to tension it.
Will need to grind a small chain window in the hubs support, but once that's done excepting adding the cable the hub system is finished.
Will make a loop over metal piece to tie the clutch levers cover to the engine case. Will be secured by short allen bolts from the front and backside.
Now its pretty much just finish the bike.

 

[silverbear]

This is very cool. I never thought I would do another China girl build, but since I have three engines sitting around gathering dust and have several 3 speed S&A hubs, I just might do one. Also found a nice mountain bike at the dump last fall that would be a good candidate.

By the way, I was glad to see you used a split collar for the transmission mount. I thank you again for that idea. Used it on the Elgin Velocipede engine mounts and shift kit mount and also am using them for the engine mounts on the "kindalikeawhizzer" build. And I will use them again!
SB

 

[cannonball2]

Glad to pass the lock collar idea along SB, it has worked well for me. Sounds like you have the basics for a concentric trans build. Not really too much fabbing involved.
Maybe one of those builds to do when everything is finished and you need something kinda quick and fun to do.

 

[LandSpeedRecord]

Cannonball, I am having trouble with my pedal side chain adjustment now also since my gearing change. On your set up would it be possible to move the 3 speed hub a bit to make moving the wheel possible to make the pedal side work?

 

[Intrepid Wheelwoman]

Ok got the drive basically finished. The chain lines are perfect! Its a close fit to the rear wheel, but there is more than adequate clearance. The pedal chain is a bit loose when the drive chains are adjusted, so will just add a small idler to tension it.
Will need to grind a small chain window in the hubs support, but once that's done excepting adding the cable the hub system is finished.
Will make a loop over metal piece to tie the clutch levers cover to the engine case. Will be secured by short allen bolts from the front and backside.
Now its pretty much just finish the bike.

Wow that's such a lovely nice and neat setup CB. This is something I'd like to try myself, predictably I would be using a Villiers engine instead of a China Girl though

 

[rustycase]

Very nice, CB2.

And thanks for the big laugh !

...'Now its pretty much just finish the bike.' the devil is in the details!

It will be fun to see how it runs out for you... should be dandy!
Steam... maximum torque at 0 rpm. Somehow, that doesn't quite mix with wire-spoked wheels. But I did very much enjoy watching the few steam cycles I have seen videos of!
Great work! Tnx for posting the nice pics.
rc