HPM 5000B - sprockets and gear ratio

Apal

1 µW
Joined
Feb 13, 2022
Messages
2
hi,
I′m building an electric go-kart with an hpm-5000b motor @48v with 11′ wheels and I got stuck on sprockets. I would like a ratio that could allow me to reach a max speed of 30mph so I calculated that I need a gear ratio of 4.118 (70 axle/17 c̶l̶u̶t̶c̶h̶ motor side) with 3700rpm. But when I tried to search for sprockets on this motor, I found only sprockets for chains that would be too large for the axle(420 chain sprocket with 70 teeth for axle = 11′15" diameter), and that wouldn′t fit on the rear axle. So I wanted to ask, what should I do? With 219 chain 70 teeth would be ok, but then I can′t find a suitable sprocket for the motor. So should I send an inquiry for a custom sprocket in some shops around me or do you have another idea?
Thank you
 
Why do you want 17 tooth primary (on the motor?)
What clutch, are you planing to use a clutch on the motor?

Is there a reason to use 420 chain, lower friction or something?
I would probably go for something like 11 tooth motor, 45ish on the axle and a 428 chain for a longer life.
If possible bigger sprockets like 12/50, 13/54 or similar for longer life.
 
I also have an electric go kart with an HPM5000B motor, I bought it with a 22 tooth sprocket (428 chain), this motor has a 7/8' shaft diameter. The split sprocket on the rear axle is 48 tooth and I achieve much more than 30mph. You can have a similar setup like mine and maybe you can limit the max rpm with the controller (if it's programmable). I also have another split sprocket with 54 tooth to try, as you already said, you can't go that much large because it won't fit on the rear axle.
 
Back
Top