scottclarke
100 W
deecanio said:im a little lost here scott, does the gearing from the motor to the rear sprocket negate the need for a stepdown box like matts? doesn't it mean that the motor takes the full load from the wheel meaning it will get rather hot under load?
i wish i had more brain
it would seem that these RC motors are way cool for use with ebikes but how best to set them up?
I take it that because the rpm is so high there's no way to run one through the gears like the cyclone setups, would this be possible using a bigger sprocket on the motor?
Anyway more pics and some video please - if your cam wont take the abuse on the bike just leave it on a wall or something and do some drive by's???
watching yours and matts build with massive interest!!!!!D
D,
Load is load no matter at what rpm.
I have a step down in the form of the sprocket and chain - its a 9.6:1 ratio as of yesterday which means if the motor span at 10,000 rpm at max volts the wheel would be going 960rpm. I plan to run on 33V as of yesterday which means my top speed is nearer 50mph with motor at 6600rpm - putting me in a bit of a sweet spot at 40mph in the 5000 to 6000rpm range.
If you wanted to be sensible you would need to gear down much further - say 20:1 but I really don't have the space for the gearbox I would need - the motor was chosen because it fits the frame exactly - and for no other reason. At 20:1 it would do 26mph and I am sure - self start just fine as well as having awesome acceleration. As mine is geared it won't self start - it needs to be moving at 1mph or so before it can spin up. This is the reason brushless motors on scooters have a centrifugal clutch fitted - allowing the motor to spin up to 300rpm or so before the drive engages - somewhat gradually.
More later - gotta run!