Rear derailleur problem
 

Hello everyone. I have a problem and have had for some time and I hope someone can help me. I have Dura Ace 10 speed shifters and rear dreailleur with a 12/27 cassette that sometimes hangs in the middle of the cassette when shifting up. I've had my LBS adjust it a friend and myself to know avail. It doesn't do it all of the time and nothing is worn out, but it is annoying especially for the quality of the components. Oh yeah the chain and derailleur are Ultegra.

Thanks for any advice you can give me.

how many miles on the chain? could need a fresh cable and housing too.

My favorite is to look at der hanger alignment. And I'm sure, to a bike, new cables and housing feels like putting on fresh socks after a long, wet ride.

The chain measures ok and the cable and housings were put on about last year this time and maybe have 2 or 3 thousand miles on them. I have thought about replacing the chain and I have not checked it real close to see if it is sticking. But I have had this problem with 2 different chains and cassettes.

Thanks...

+1. Dura Ace 10-speed. As the cassette cogs are spaced more closely together, derailleur hanger alignment becomes progressively more critical.

I'll take a closer look at the hanger, but it is on a Litespeed with a Ti hanger. I know they'll bend but not quite as easy.

Thanks...

Have you checked your B-tension screw adjustment? (I'm assuming DA 10s has one) The LBS should have, but look again, or just screw it in a little and experiment.

I recently had a very similar problem with my 105. I gave up trying to fix it myself and took it to the LBS; he couldn't fix it and although the chain had few miles on it I agreed to put on a new one. No change. He lubed the cables etc and the shifter and it improved a bit. I later squirted more silicone lube into the shifter and that seems to have fixed it. So try lube in the shifter/brifter.

I was going to lube the cables tonight, but I didn't think about the shifters. My LBS also mentioned to make sure there are no burs on the chain where the link was put in and broken off. Since I installed both chains this is a possibility.

Thanks...

Well I found out what the culprit was during a 75 mile ride on Saturday. I was about 12 miles from the end when the cable snapped leaving me with 2 gears hard and harder. I took it to a different shop and he replaced the cable but noticed it still wasn't shifting right so he flipped the bike over and for some reason the cable was catching underneath the derailleur. He put a little washer on and then tightened the cable which did the trick. I really don't know how that happened other than I was working on it and broke the lipe off of the clamp and my LBS put another one on. It must have been off of a different derailleur and not as thick I assume.

Well the good news is it shift great now. Thanks for all of you suggestions.

An extra cable takes up very little room in the bag, but if this happens without one handy, you can always tighten your limit screw down to hold the RD in an easier gear. Glad you solved it. :)