Hey guys.
I'm looking for some advice. I'm starting my first motorized bike project. I'm trying to figure out how to setup a sprag clutch in my pedal assembly so that I can run my engine through my 27 gear drive train, already on my bike.
I'm sure it's possible, but I'm not sure where to start. Can anyone point me in the right direction? Other than GMN Bearings and Clutches, I haven't found a provider for a sprag clutch, outside of stripping it out of another mechanism or machine.
Let me give you a description of the project so far.
I'm working on locating the proper engine. But I'm looking at the engine on the Stihl 660 (90cc) or Stihl 880 (120cc) model chainsaw. They're high torque, and the 660 has one of the best power to weight/size ratios of nearly any small engine out there.
I'm looking to take one of these engines and mount it behind my seat, and run a chain drive down to the smallest of the 3 gears on the pedal sprockets. I face a couple potential problems.. due to the design of the rear fork on the bike, I'm running into the problem of chain rub on the chassis.
As I mentioned, I need to figure out how to setup that sprag system in the pedals and I need some advice for some heavy duty rims.
I went to the local bike shop and nearly was laughed out of the store, because I was "picking the wrong brain" about engine driven wheels. (The guy was an ass)
Sooo.... needless to say, I need some advice on strong rims, with a couple different specifications..
It needs to have:
Disc brake mount
Freehub cassette mounting
double wall
heavy duty spokes
I'm also looking for some general information regarding the gearing.
What info do I need to get together to figure out the ratios to get a rough top speed?
What sort of concern should I have for an engine of this size on a regular chain for a bicycle?
What sort of concern do I need to have for the bearings?
I'm taking this bike a bit further than the average motorized bike.. so I'm not sure how much I need to worry about over torquing the chain or stretching it, or overrunning the bearings and burning them out... that sort of thing.
My goals are:
Good suspension
roughly 100cc gas engine
multiple gear system
Disc brakes all around
and of course, doing it all safely.
Any advice would be greatly appreciated.
Thanks,
Marc
I'm looking for some advice. I'm starting my first motorized bike project. I'm trying to figure out how to setup a sprag clutch in my pedal assembly so that I can run my engine through my 27 gear drive train, already on my bike.
I'm sure it's possible, but I'm not sure where to start. Can anyone point me in the right direction? Other than GMN Bearings and Clutches, I haven't found a provider for a sprag clutch, outside of stripping it out of another mechanism or machine.
Let me give you a description of the project so far.
I'm working on locating the proper engine. But I'm looking at the engine on the Stihl 660 (90cc) or Stihl 880 (120cc) model chainsaw. They're high torque, and the 660 has one of the best power to weight/size ratios of nearly any small engine out there.
I'm looking to take one of these engines and mount it behind my seat, and run a chain drive down to the smallest of the 3 gears on the pedal sprockets. I face a couple potential problems.. due to the design of the rear fork on the bike, I'm running into the problem of chain rub on the chassis.
As I mentioned, I need to figure out how to setup that sprag system in the pedals and I need some advice for some heavy duty rims.
I went to the local bike shop and nearly was laughed out of the store, because I was "picking the wrong brain" about engine driven wheels. (The guy was an ass)
Sooo.... needless to say, I need some advice on strong rims, with a couple different specifications..
It needs to have:
Disc brake mount
Freehub cassette mounting
double wall
heavy duty spokes
I'm also looking for some general information regarding the gearing.
What info do I need to get together to figure out the ratios to get a rough top speed?
What sort of concern should I have for an engine of this size on a regular chain for a bicycle?
What sort of concern do I need to have for the bearings?
I'm taking this bike a bit further than the average motorized bike.. so I'm not sure how much I need to worry about over torquing the chain or stretching it, or overrunning the bearings and burning them out... that sort of thing.
My goals are:
Good suspension
roughly 100cc gas engine
multiple gear system
Disc brakes all around
and of course, doing it all safely.
Any advice would be greatly appreciated.
Thanks,
Marc
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