Just a word of caution about "quick links" and the NEWER Shimano (Ultegra 6700 and DA 7900) chains....

I recently replaced the stock chain (a SRAM 10spd) on my Cannondale Synapse. I wasn't happy with the way the chain was shifting and it was very noisy, too. Since most of my drivetrain (with the exception of my crank) is made up of Shimano Ultegra 6700 components, I opted to go with the 6700 chain. While I was at the LBS buying the chain, I was talked into getting one of those "quick links"...or as my LBS calls them "super links". My DH put the chain and superlink on my bike, and shortly after that is when I started to have some issues. I kept feeling a strange "clunking" sensation in my crank. For weeks this went on, until I finally broke down and brought the bike back to my dealer. They inspected the bottom bracket, the free wheel, the pedals, everything they could think of. When I got the bike back, I took it for a spin and the clunking was still there. My DH put the bike on our bike stand and after several frustrating hours of trying to figure out what was causing the "clunking", we finally struck gold! It was INDEED, the superlink getting caught up in the top jockey wheel of the rear derailleur. Every single time that superlink passed through that jockey wheel, it was rubbing the side of it...thus causing the clunking sensation that I was feeling through my pedals. I called my dealer up and ran our theory by them, and they did confirm to me that Shimano at one time, was packaging a quick link with their new DA 7900 chains, but started receiving many complaints similar to mine...so they have sinced pulled the quick links from the packaging and are now encouraging users of the new Shimano chains to use the conventional "pins" when installing the chain. As soon as we took out that superlink in my chain and replaced it with the regular "pins" that it came with, the bike ran smooth and quiet. I know there will be some folks out there that will argue this, but personally, I am convinced that the newer Shimano chains simply do not run well with ANY type of quick-connecting link.

Linda