#40 chains

[copyman]

I thought most mini bikes used #35 chain? I'm rebuilding a Terra Pony 444 (didn't come with chain) and went to put a #35 chain on it and realized it takes a larger size. I had an old #40 chain and it fits the wheel & drive sprocket fine but looks really beefy. Is there another larger size chain that would of been used on a 1970-71 Terra bike with TC belt and driven jack shaft to sprocket & chain to rear wheel on opposite side?
After I posted this I did a little a research and looks like mini bikes would use a #420 chain rather than a #40. Does this sound right?
Thanks

 

[Jim Donovan]

Yes, just measure the thickness of the sprocket. #41 and #420 are the same chain and they are both are used on sprockets that are .227 thick. #420 is just pre-stretched #41 chain. #40 sprocket is thicker and it will measure .284 the chain is a lot beefier than the #41 or #420. Most 1/2" chain sprockets are made for the #41/#420 chain but will handle the #40 chain also but it will be a little loose but that also helps with alignment. But if you have a #40 sprocket it will only take a #40 chain.

The 1/2" pitch chain you want to avoid is #428 which has a much bigger roller and it will not go all the way down in the valley of the sprocket on a #41 or #40. The #428 chain is used on motor cycles.

I like using the #40 chain on the #41 sprocket because if they are not perfectly align there is some built in forgiveness.