Key for Transmission > sprocket location

where is the key used to connect the transmission to the sprocket.

is it in the parts kit or does it have to be purchased seperately.

if it has to be purchased seperately, what is the size of the key

If your using the given trannies they should be in there. but if your building youyr own you’ll need to buy them or cut them yourself

no, im looking for the long square key that connects the transmission shaft to the sprocket that drives the chain for the wheels

It is a 1/8" square key.

They are available form popular suppliers such as mcmaster carr and msc.