Chain does not fit sprocket - please help

[atomicmiata]

Hi,
my first post here.
I just bought an engine kit off ebay from boygofast.
an 80cc kit. (I know it is probably -70cc)
the chain pitch does not jive with the rear sprocket pitch.
(it appears that the chain would need to stretch considerably to fit)
anyone seen this before?
should I buy a new chain? what size?
or buy a new sprocket? if so, from where?




thanks!
steve in frederick, md

[misteright1_99]

I changed the chain out with #41 roller chain. I got mine at Tractor Supply Co. It was around 12.00 for 10 feet....While you are there you might check to see if they have a spring loaded chain tensioner.


http://motorbicycling.com/f6/spring-...ioner-890.html

[Goat Herder]

http://motorbicycling.com/f3/trouble...hain-2602.html. don't know how to post everthing on this forum yet. this post says the teeth are raised too high on some of the older kits, for the rear sprocket. the idea was to use a dremal tool and knock the teeth down a little won't hurt nothing. Hope this helps

[Bikeguy Joe]

boy go fast huh? Hmmmmm, seems to be a pattern here. Have you contacted him about a chain and or sprocket replacement?

[OSCAR383]

just wondering the chain appears to be seating on the bottom side of sprocket do you have the sprocket parallel with the tire or perfectly centered on rear rim. that was the problem with mine when i first put together

[Bikeguy Joe]

I got a fit like that when I tried to use a bicycle chain on the drive sprocket...

[atomicmiata]

I took the sprocket to a motorcycle shop today to try a different chain on it.
a 420 sized chain fit the pitch of the sprocket perfectly, tho a 420 is quite a bit wider which is not good.
anyone know of another size chain that has the pitch of a 420 but is narrow in width?

thanks!
-steve in frederick, md

[Saddletramp1200]

Ok the coating on the sprocket is too thick. Dax says use a grinder to gently "buff" the plating off of it. I am never one to follow and took mine outside and found a rough piece of sidewalk. Scraped it till it looked good. Not much! just a little. Both sides.

[Bikeguy Joe]

Originally Posted by atomicmiata

I took the sprocket to a motorcycle shop today to try a different chain on it.
a 420 sized chain fit the pitch of the sprocket perfectly, tho a 420 is quite a bit wider which is not good.
anyone know of another size chain that has the pitch of a 420 but is narrow in width?

thanks!
-steve in frederick, md

#41 chain from the Tractor Supply Co. or other places is a perfect fit to the standard China In-Frame kits.

[Bikeguy Joe]

Also called #415 or #415H in the bicycling world.