lclarkberg
1 µW
Hi all. I am considering building a dual hub motor (2WD) bike with a direct drive motor on the front and a geared motor on the rear. Some background: my first electric bike was a Big Dummy longtail cargo bike with a Stokemonkey mid-frame motor. Because the Stokemonkey is geared down both with a chain going from the motor to the pedals and a chain going to the freewheel it has incredible hill-climbing power--it's like a power winch on wheels. It's slow going, but it could climb even the steepest hills on 600W. I could easily carry my 11-year-old daughter and four bags of groceries up the steepest hills in Ithaca.
I recently upgraded to a much more powerful 3KW bike with 10s1p lipos and a Crystalyte HS3540 motor. It's fast, but surprisingly not a good a hill climber. A quick trip to Justin's simulator shows that in order for this bike to put out maximum power up a hill I need to limit my load and maintain 20mph or so.
It occurs to me that I'd like my bike to have both a geared motor for hill climbing (maybe even with a 24" or 20" rim) and a direct drive motor for greater power on the flats. This would in effect give my bike two "gears", a low gear for the hills and a high gear for the flats. I might try two throttles at first to get a feel for it. Eventually I'd make a single throttle that runs the geared motor first and then shifts to the direct drive motor. I would put the geared motor on the back for better traction, and if the geared motor had a smaller rim the shorter profile could give my cargo bike more cargo space.
Most dual hub builds I've seen have both hub motors the same type. Has anyone out there tried mixing both types of motor? Any advice?
I recently upgraded to a much more powerful 3KW bike with 10s1p lipos and a Crystalyte HS3540 motor. It's fast, but surprisingly not a good a hill climber. A quick trip to Justin's simulator shows that in order for this bike to put out maximum power up a hill I need to limit my load and maintain 20mph or so.
It occurs to me that I'd like my bike to have both a geared motor for hill climbing (maybe even with a 24" or 20" rim) and a direct drive motor for greater power on the flats. This would in effect give my bike two "gears", a low gear for the hills and a high gear for the flats. I might try two throttles at first to get a feel for it. Eventually I'd make a single throttle that runs the geared motor first and then shifts to the direct drive motor. I would put the geared motor on the back for better traction, and if the geared motor had a smaller rim the shorter profile could give my cargo bike more cargo space.
Most dual hub builds I've seen have both hub motors the same type. Has anyone out there tried mixing both types of motor? Any advice?