QuadManiac
Member
Another option is to get the motor with the recently available pull start and centrifugal clutch. The centriugal clutch has a one-way bearing (equivalent to a free-wheel) so you can still start the motor using the pedals and it still has the stock clutch too. It does make it wider (6 7/8") but i mounted my engine a little higher (with the SPB shift kit) and filed just a bit from the Sick supplied wider cranks and voila, works like a charm.
Had it together for about a week now, have 30 miles on it (with the 6 speed rear derailleur gearing driven by the SBP jackshaft) and it is sweet! Starts cold with the choke within 2 or 3 pulls on the pull start or just one good push on the pedals... with the low gear, acceleration from a stop with the centrifugal clutch is immediate even on hills and the cent clutch seems to engage very quickly without slipping much at all. It pulls hills with ease in low and in the top gear I'm seein 29 mph even with lower breakin RPM's. I only use the standard clutch while using the pull starter, to pedal w/o engine or to back the bike up.
BTW, i originally started with an Autobike Classic which has the rear derailleur controlled by rear wheel speed, esentially a simple automatic transmission. This was fun, but after riding it a bit i realized that the shift points and seperation were not very appropriate for an engine driven bike. ALways seemed to be in the wrong gear at the wrong RPM even after adjusting the system to try to optimize... so I went back to a regular thumb shifter controlled derailleur and am extremely happy now; and plan on changing to a twist grip shifter soon.
After minor adjustments this has turned out to be exactly what I was hoping for.
Good luck in your build!
Had it together for about a week now, have 30 miles on it (with the 6 speed rear derailleur gearing driven by the SBP jackshaft) and it is sweet! Starts cold with the choke within 2 or 3 pulls on the pull start or just one good push on the pedals... with the low gear, acceleration from a stop with the centrifugal clutch is immediate even on hills and the cent clutch seems to engage very quickly without slipping much at all. It pulls hills with ease in low and in the top gear I'm seein 29 mph even with lower breakin RPM's. I only use the standard clutch while using the pull starter, to pedal w/o engine or to back the bike up.
BTW, i originally started with an Autobike Classic which has the rear derailleur controlled by rear wheel speed, esentially a simple automatic transmission. This was fun, but after riding it a bit i realized that the shift points and seperation were not very appropriate for an engine driven bike. ALways seemed to be in the wrong gear at the wrong RPM even after adjusting the system to try to optimize... so I went back to a regular thumb shifter controlled derailleur and am extremely happy now; and plan on changing to a twist grip shifter soon.
After minor adjustments this has turned out to be exactly what I was hoping for.
Good luck in your build!
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