#### BrettMavriK

##### Member

I've been trying to calculate numbers for my homemade intermediate jackshaft

plans, so I can purchase the sprockets. I know gear reduction is needed, but how much for these motors? 4:1? 3:1? 6:1?

And I know I'm not calculating it correctly. (wish I knew the formula)

I know the motor has a 10 tooth on it, and I'm using a Sturmey Archer 3 Speed Hub on the 20" Stingray rear wheel.... it's just the in between gears on the jack shaft I'm having trouble with.

I was thinking of the first sprocket from the motor on the jackshaft would be an 18t. Then from there, I get lost and don't know if I should be going down in reduction or up in multiplication.

Anyone have a good equation to figure this out???

Thanks in advance,

'BrettMavriK