Originally Posted by
chikatetsu
Hi everyone,
I have a 2008 Cannondale System Six 3 which, until recently, has been running on stock components. I recently changed the rear cassette from the 12-25 to a more forgiving 28 (both Ultegra parts) but it seems like cassette is the wrong size. For example, when I'm in the largest rear cog, it looks as if the top jockey wheel is too close to the cog teeth and the chain can't run through smoothly enough. Is a 28 teeth ring just too large or can I just adjust the derailleur arm (using the b-screw IIRC) to move everything down to create more clearance? I hope that this makes sense and that someone can help。
The B screw should move the pulley away from the cog. I have also heard of people swapping the pulley itself for a smaller size (typically 11t to a 10t) to get more clearance.
IIRC you can get a joining link and add that to your existing chain, but you may need to add two to get the length you want, and not sure if adding 2 is recommended.