golfer007

So after doing my bike, my chain seems to be just a little off. There is a slight clunking noise when I really hammer on it. I was told it is the chain moving around on the free wheel. The noise is sparatic and only comes at certain times. I just converted my girls new Varsity to a SS and the same noise is occuring. Am I doing something wrong? What is the best bet to correct the chain line. I am running a Sugino XD with a Shimano BB. Should I get a shorter/longer BB to correct this noise?

Thanks,
Freelander

joetronic

next time you do your bike be a little gentler. Sometimes they like it that way.

really though, it sounds like you have 1/8" chain and 3/32" cog and chainring, or your chainline is off. Lokk up Sheldon's article on chainline.

golfer007

No, not that I know if. Both free wheels are 3/32 and same with both chains as far as I know.

onetwentyeight 

1) measure the distance from the inside of the left and right rear drop outs (rear spacing). Divide that by two.
2) measure the distance between the center of the teeth on the freewheel and the right drop out. Subtract that number from the half of rear spacing.
3) measure the distance from the center of the seattube to the teeth on the chainring.

the difference between the two numbers you have is how off your chainline is. You can correct your chainline by either moving where your chainring is if you have a road crank (from inside to outside) or by getting a bb that is that different from what you have now. Or you can get a bb where you have some adjustment and correct by that much.

golfer007

Wow, thanks. I will have to check it out. I tried moving the chainring to the inside of the cranks and it was very close to hitting the frame. I had a couple guys tell me that the chain would definitely hit under hard peddling.