Most BOB pushers I researched either use sprocket driven external motors or weld longer replacement forks to accomodate larger than 16" diameter wheels. I've wondered what simple Hub motor conversion with adequate speed can be done effectively on a stock BOB Yak.
Looking at the ebikes.ca simulator at this HS2440 72V 40A motor-controller combo I note that peak 100% throttle output watts at 82V on a 15.5" OD wheel is about 22mph (dropping to zero at 37mph).
The ID of my stock BOB 28-spoke 16" rim on 100mm hub appears to be about 11" ID and calipers suggest that it is about 26mm wide at the rubber to rim edge.
Crystalyte's drawings for the HS24 motor shows an OD of 239mm which = 9.41"
Is there enough spoke room to lace a HS24 into a 36 hole rim that will take a 47-305 tire like the Schwalbe Marathon Kevlar 368? If so, what rim would you recommend and what forum member wheel buiders could and would cut extremely short spokes and lace the wheel?
Assuming I use 40 pounds of 20AH prismatic batteries mounted in the rear of the trailer with the controller would I be able to avoid standing start wheel spinning (and extremely limited tire life) on takeoff? The simulator shows torque of 107 pound feet at start-up at 82V.
Will the unpowered cogging of the motor sufficiently reduce destabilizing trailer forward inertial forces when I brake the bike?
Looking at the ebikes.ca simulator at this HS2440 72V 40A motor-controller combo I note that peak 100% throttle output watts at 82V on a 15.5" OD wheel is about 22mph (dropping to zero at 37mph).
The ID of my stock BOB 28-spoke 16" rim on 100mm hub appears to be about 11" ID and calipers suggest that it is about 26mm wide at the rubber to rim edge.
Crystalyte's drawings for the HS24 motor shows an OD of 239mm which = 9.41"
Is there enough spoke room to lace a HS24 into a 36 hole rim that will take a 47-305 tire like the Schwalbe Marathon Kevlar 368? If so, what rim would you recommend and what forum member wheel buiders could and would cut extremely short spokes and lace the wheel?
Assuming I use 40 pounds of 20AH prismatic batteries mounted in the rear of the trailer with the controller would I be able to avoid standing start wheel spinning (and extremely limited tire life) on takeoff? The simulator shows torque of 107 pound feet at start-up at 82V.
Will the unpowered cogging of the motor sufficiently reduce destabilizing trailer forward inertial forces when I brake the bike?
