Topic: ok, so how exactly do you figure chain size?

[wornknobby3]

ok so i have a 1978 750k and i had the stock sprockets 15/41, but now i'm going to a 530 set-up of a 17/48, so now im trying to figure out how many links roughly i would need. I saw some where on this site that 92 links from a 630 = 110 from a 530, but wasn;t sure on how to go about doing this.

[754]

Easy..
 Take the sprocket measurement at pitch center, X pai, then divide that by 2..

 Do that for both sprockets..

 Now take the center to center distance of the sprockets and X by 2

Now add the 2 sprocket diameter divided in 2, then add the c-c X2,, then take the number of inches and X by 2 if you are using 1/2 inch pitch chain.

The formula is 100 % accurate if both sprockets are same size, so if not, a slight adjustment using trig may have to be factored in...

Easy huh??

 If that is  a bit hard to follow wait till someone posts tooth count..

[wornknobby3]

whoa, well it seems u know what your doing then., could u happen to figure that out for me? i'm just going from stock 15/43 630 size to 17/48 530 size. if that isn't a problem?

[wornknobby3]

ahh yes i saw that link before, i ddin't see the chain sizing on there, thanx!!!! came out to be about 105.2 but i'll go w/ a 108 just incase of sprocket changes made early