Deacon and I were kickin' it back and forth last night and we had some amazing ideas bouncing off deacons idea of using a bottom bracket as a jack shaft ( see work in progress thread.).
What if you raid a donor bike for parts, and I mean for things other than the easy stuff like brakes, lever etc....
For instance, you could cut a bottom bracket out flip it, use part of the old frame to mount it inside of the other bike frame and mount gears on each side. Ghetto jack shaft.
or what if you used an old mountain or road bike hub with a freewheel mounted with your quick release above the tire into a drive spindle? with the engine mounted above that and a chain driving the hub. hub rubs the tire and presto free wheeling drive wheel that has a change-able gearing- one could even rig up a fancy pants gearing system with a derailleur. also the best thing- no need to remove the spindle if the engine isn't running- freewheel.
flip the engine, bolt a small gear to one side of the hub and keep the cassette on there and instant freewheeling jack shaft. You could mount it pretty much anywhere- in frame etc. the only issue is how to mount it. because the bub itself is spinning you have to consider that your chains all have to run inside or around the mount, also the engine would need to be offset to account for the length of the hub- they are pretty short.
With the current model of friction drive that D and I are running the engine is hanging off the side of the bike, off setting it an inch or 2 would alleviate some of the center of gravity issues also, removing the spindle from direct engine contact would alleviate A TON of pressure off the engine. And save a lot of wear and tear too. Also as D pointed out- you can keep more of the plastic housing that helps to keep the engine cool and cut down on engine vibration.
Obviously it makes building a friction drive a lot more difficult- not as easy as ripping apart the whacker and attaching a spindle. BUT at the same time how easy would it be to use the hub with gears to make an in frame design?
cheap and pretty easy to do.
What if you raid a donor bike for parts, and I mean for things other than the easy stuff like brakes, lever etc....
For instance, you could cut a bottom bracket out flip it, use part of the old frame to mount it inside of the other bike frame and mount gears on each side. Ghetto jack shaft.
or what if you used an old mountain or road bike hub with a freewheel mounted with your quick release above the tire into a drive spindle? with the engine mounted above that and a chain driving the hub. hub rubs the tire and presto free wheeling drive wheel that has a change-able gearing- one could even rig up a fancy pants gearing system with a derailleur. also the best thing- no need to remove the spindle if the engine isn't running- freewheel.
flip the engine, bolt a small gear to one side of the hub and keep the cassette on there and instant freewheeling jack shaft. You could mount it pretty much anywhere- in frame etc. the only issue is how to mount it. because the bub itself is spinning you have to consider that your chains all have to run inside or around the mount, also the engine would need to be offset to account for the length of the hub- they are pretty short.
With the current model of friction drive that D and I are running the engine is hanging off the side of the bike, off setting it an inch or 2 would alleviate some of the center of gravity issues also, removing the spindle from direct engine contact would alleviate A TON of pressure off the engine. And save a lot of wear and tear too. Also as D pointed out- you can keep more of the plastic housing that helps to keep the engine cool and cut down on engine vibration.
Obviously it makes building a friction drive a lot more difficult- not as easy as ripping apart the whacker and attaching a spindle. BUT at the same time how easy would it be to use the hub with gears to make an in frame design?
cheap and pretty easy to do.