BigK75

Hey Guys:

I have a quick question for you guys. I want to buy a KMC X10SL chain for my bike as the other one is worn. I notice some come in 112 links, some 110 and others in 116. How do I know which one to buy? I have a Madone 5.2 bike with 53/39 and 11/28 cassette. I don't to buy one that is too short so I thought I should ask before I buy off of ebay and make a mistake.

Claude

Marauder9

Count the number of links on the chain you already have then at least you know you have a chain that fits.

HillRider

Most chains come longer than needed for typical gearing and have to be shortened at least a few links to fit properly so there is no such thing as too long initially as long as you cut it to fit your particular bike. Most Shimano chains are 116 links and Wippermann are 114 and I've had to shorten them all by at least 4 links to cover a 53T chainring and a 29T big cog situation.

Get the 112 or 116 link length and a good chain tool. Sheldon Brown has an article that includes instructions for setting chain length based on "Big-Big" (largest cog + largest chainring) that gives the shortest chain that will safely let you shift into that gearing combination. You should never use it intentionally but if you do accidentally, the chain MUST allow it or the damage can be significant. Look here and scroll down to the "Chain Length" section: https://sheldonbrown.com/derailer-adjustment.html#chain