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Discussion Starter · #1 · (Edited)
Hello all. I'm new to the board and I have been reading through several pages of archived files on "chain" noise. Yet, I am not sure if I found a thread that describes my exact situation.

I just purchased a 2010 CAAD9 5 (with Shimano 105 group) from a LBS. It is factory stock and there is a noise that I just don't think should belong in a new bike. (This is my first nice road bike. My other bike is a commuter/hybrid Giant FCR3 w/ Shimano Altus RD).

First of all, I test rode both a Synapse 5 (Shimano 105 group) and a CAAD9 5 (Shimano 105 group w/ BB30) over a same 6-mile round trip route. Synapse 5 rode so quiet and the shifts were buttery smooth. The only noise came from the tires.

When I rode the CAAD9, it made "chain" noises when using the big ring and middle gears in the rear cassette. The noise was definitely cyclical in nature as it occured in every 1-2 revolution(s).

After the test ride, I knew that I wanted CAAD9 5. But, I wanted the noise to be gone. So, the mechanic adjusted the setup and when I rode it again the "chain" noise was gone. However, the gears did not shift smoothly at all. At one point, riding big ring and going up & down on the middle gears in the rear, the gear would not _downshift_ even after 10-20 revolutions! (Upshifts were fine) So, it got adjusted again. The gear shifts ok (but not as smooth as the same 105 group on the Synapse 5), but now the "chain" noise is back.

In short, (1) what should I tell the mechanic to resolve this noise issue? (2) Or, should I just go to a different bike shop? (3) Or, try to adjust the setup myself?? (If so, what should I tackle first??) (4) I really like CAAD9 5 over Synapse 5, but swap the bikes???? :(

Thanks for reading and TIA for your input.

-Sean (happy about the bike, but frustrated w/ the group/chain setup)
 

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My guess is that the Synapse had the newer 105 group set and the CAAD9.5 had the older one. There is vast improvement in the newer version. My understanding is the front derailliuer in the older 105 was a little more finiky because it is set up to work with a triple.
 

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My first thought was the front derailleur but you are saying the noise only happens on the middle gears of the rear cog? It's silent on the smallest and largest? If so it's not your FD.

What do you mean by middle gears?
 

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Discussion Starter · #4 · (Edited)
tomcho said:
My first thought was the front derailleur but you are saying the noise only happens on the middle gears of the rear cog? It's silent on the smallest and largest? If so it's not your FD.

What do you mean by middle gears?
I apologize for my poor description, but I am new to the cycling jargon.

What I meant by the middle gears was counting from the smallest gear on the cassette, I start to have noises when I am in 3-6th gear from the smallest one.

I do not have any noise from the smallest and largest rear gears.

Also, I do not have any noises when I am on the small ring up front.

BTW, I have a standard (2 front ring) setup, not triple or compact.
 

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I'm far from an wrenching expert, but that seems like a very odd problem. Typically noises from rubbing either against the front derailleur or other rings in the rear cog happen at extremes; i.e the smallest or largest rear gears, due to the chain angle. To only have noise in the middle gears is a head scratcher for me.

I'm sure someone who knows a lot more then myself will chime in.
 

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Very simple, my dear Watson.

Cosworth said:
I apologize for my poor description, but I am new to the cycling jargon.

What I meant by the middle gears was counting from the smallest gear on the cassette, I start to have noises when I am in 3-6th gear from the smallest one.

I do not have any noise from the smallest and largest rear gears.

Also, I do not have any noises when I am on the small ring up front.

BTW, I have a standard (2 front ring) setup, not triple or compact.
You start to have noises in 3-6th gear from the smallest one, only in the big chain ring!

The outer cage on the front derailleur is rubbing on the chain in these gears. The derailleur cage is not shifting far enough out. Unscrew the adjusting nut counter clockwise on the shift cable a half turn to tighten the cable and make it pull the front derailleur further out. If it doesn't go further out, unscrew the outer travel stop screw on the front derailleur to allow more travel. Check to see if the cage clears the chain in the large chain ring and smallest cog in back. :idea:
 
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