Bicycle Mechanics - Rear derailer issues or chain?

My wife got me a new bike from craigslist and I am having issues shifting. I managed to break my chain last week (The quickpin came off somehow) So I got a new SRAM chain and I don't seem to have any sucess. I took it to the LBS and they didn't seem to get it any better.

When riding the chain appears to be rubbing the cog next to it. I tried rotating the barell and it doesn't seem to get rid of the rubbing. The other problem I have is that when I am in the smallest gear it will occasionally pop to the next higher gear then pop back. The derailer is a Simano 105.

Any ideas on what to do?

Take it back to your LBS, they may have overlooked something so you may want to ask them to check the hanger alignment, All shops should have the tools. Sounds like it's one of the following:

-hanger alignment
-cable tension
-corrosion/dirt, etc in cable housing or kink in cable
-bad shifter

As for the chain derailing up to the second highest cog when all cable tension is gone, it is either the limit screw or the hanger

A bent hanger would cause all these symptoms though, so I would definitely get that checked out.

Thanks, I'll have the hanger checked out. What should I expect the range to be to get the hanger fixed/replaced?

I charge $10-$15 to align a hanger.
TO replace it would be about double that after the part and labour.

I took it in and they fixed it today. The hanger was slightly out of alignment (some kick out) but not bad. They did say that the biggest issue is that the deraileur is a triple rather than a double which will cause shifting to be choppy and potentially cause me to have it realigned regularly.

What do you think I should do? Get a replacement short arm deraileur or live with the current setup. My current setup is a double ring compact crank with a 11/23 shimano 10 speed cassette.

They did say that the biggest issue is that the deraileur is a triple rather than a double which will cause shifting to be choppy and potentially cause me to have it realigned regularly.

What's the shop? I'd like to avoid them... thanks!

What's the shop? I'd like to avoid them... thanks!

Sammamish Cycle. Why? did they say something wrong?

The only difference between a "double" and "triple" derailer is the length of the cage. People with triples ride with long-cage derailers and don't suffer from continual shifting issues! And the idea that riding with a long-cage derailer means you will need to get it aligned more frequently... huh?

Sounds to me like they're talking a bit of nonsense, unless they said something different than what you wrote.

The only difference between a "double" and "triple" derailer is the length of the cage. People with triples ride with long-cage derailers and don't suffer from continual shifting issues! And the idea that riding with a long-cage derailer means you will need to get it aligned more frequently... huh?

Sounds to me like they're talking a bit of nonsense, unless they said something different than what you wrote.

He said the issue was how close the gear on the deraileur gear is to the cassette gear and the tension on the chain. Apparently the double is closer to the gear and the chain has a tighter tension.

He said the issue was how close the gear on the deraileur gear is to the cassette gear and the tension on the chain. Apparently the double is closer to the gear and the chain has a tighter tension.

Sounds bogus to me, but I'll wait for the experienced mechanics to weigh in on who the carpet-smoking muppet is: me or the shop guy...

:rolleyes:

Anyone else have any thoughts on this?

Your LBS shop is right about the shifting being affected negatively by your long cage derailleur.
Assuming you're running an 11-23 cassette, and 34-50 chain rings, your calculated chain wrap capacity would be 28. SHimano SHORT cage derailleurs are rated for a CWC of 29, which would be ideal.

Typically road LONG cage derailleurs will be rated for a CWC of 37 or so.
WHat this means is that the derailleur is putting more tension on the chain to prevent it from hitting the cogs or "drooping around", and too much tension would seriously affect the shifting, especially on 10 speed systems which place the cogs so closely together.

It is always best to get a derailleur that is rated the closest to your calculated chain wrap capacity, without exceeding that limitation. (ie; not getting a derailleur that is rated for a 28 with a CWC of 29)

C'mon guys, help me out here!

The fact you are running an 11-23 means you aren't shifting a lot of teeth at a time, so shifts SHOULD be pretty smooth. Cheaper MB's can shift "decently" with much bigger jumps.

Is the chain the proper length for your set up? IF it's too long, there would less tension.
Shift the gears to the big:big combo and pull ALL the slack out of the chain. You should have 1 link set (+ whatever fraction of a set) extra.

The fact you are running an 11-23 means you aren't shifting a lot of teeth at a time, so shifts SHOULD be pretty smooth. Cheaper MB's can shift "decently" with much bigger jumps.

Is the chain the proper length for your set up? IF it's too long, there would less tension.
Shift the gears to the big:big combo and pull ALL the slack out of the chain. You should have 1 link set (+ whatever fraction of a set) extra.

I think the chain length is correct, the LBS didn't complain about it.

I'm now in the market for a 105 short rear deraileur and a 12/27 cassette. It sounds like when I come up with the cash for those I'll need to have the LBS install them since I don't have the tools for changing the casette.

Is it worthwhile to upgrade the de-raileur and casette to ultegra or should the 105 be good enough. The pricing online doesn't appear to be much different between the two. I'm assuming my 105 shifters will work with ultegra as well.

Thanks for all the help.

"...I took it to the LBS and they didn't seem to get it any better."
"What's the shop? I'd like to avoid them... thanks!"
" Sounds to me like they're talking a bit of nonsense, unless they said something different than what you wrote."
" I think the chain length is correct, the LBS didn't complain about it."

Did they actually check it, or just ASSume it was correct?
It'd take 2 minutes for you to check it and cost you $0! Then you would know for sure IF that might be the source of the problem.

"...I took it to the LBS and they didn't seem to get it any better."
"What's the shop? I'd like to avoid them... thanks!"
" Sounds to me like they're talking a bit of nonsense, unless they said something different than what you wrote."
" I think the chain length is correct, the LBS didn't complain about it."

Did they actually check it, or just ASSume it was correct?
It'd take 2 minutes for you to check it and cost you $0! Then you would know for sure IF that might be the source of the problem.

The first LBS was no help. The second LBS fixed it up and was the one that told me about the deraileur issue. Sorry to confuse the issues.

He played with the chain but didn't remove it to wrap. What is the best way to check the tension on the chain?

"What is the best way to check the tension on the chain?"
The way I stated on my ealier post.

I'm now in the market for a 105 short rear deraileur and a 12/27 cassette.

If you are changing your cassette to an 11-27, stay with the derailleur you have (long cage) or find a medium cage derailleur.

I guarantee you will have CWC problems running a short cage derailleur with an 11-27 and compact cranks.