Originally Posted by
Trenton
So... just to add an ending to this story for now, I'm going to try a mid-compact DA 9000 crank (riding 40+ miles this afternoon in Lancaster/York counties). First impressions from the stand is the new 9000 crank-set is noisier than the DA-7800. Of course, not an issue on the road. The other thing I did (wrong/incorrectly) was shorten the chain, so I'm a bit nervous. With the 52/36 crank, and pedaling in the 36 up front and 28 in the back, I could hear additional noise in the back - not that the rear derailleur was bouncing off the 28T, just noticeably noisier, kind of a grinding sound. I pushed the hanger adj, B-screw all the way in to push the derailleur off the 28T to no avail... so I cut out a link of the chain. That worked BUT if I use 52 & 28, the rear derailleur is basically a straight line and once stuck the crank, ergh!
Not sure what's next... OTHER than never using 52/28 or even 52/26 combos.
I'm thinking about replacing the rear DA-7800 with a DA-9000 rear derailleur - thinking, well hoping DA-9000 has a longer cage. Does anyone know if that's the case? The DA-9100 rear cage certainly looks longer but it's mounting bolt area seems different than the mount for my DA-7800 derailleur.
Anyway, thank you everyone for helping me. Trent.
A couple of comments:
- cross-chaining (52/28) is usually a bad idea. You should shift to the small ring before you get to the smallest cog. The chain needs to be long enough to handle it, but that doesn't mean you should ride that way.
- I don't think shimano recommends mixing 10 and 11 speed shifty bits, or if it can even be made to work. You are probably ok with the 11 speed crank, but if you go to a 9100 derailleur, you will likely also need 11 speed shifters, cassette and chain.