Chain length - not quite right???

[sharpy]

Hi,
I have just fitted a new campag medium cage rear derailleur to bike to accomodate the 13-29 ten speed cassette also recently fitted (running a 34-50 compact chainset)
At the same time I decided to fit a new chain.
In order to size the chain I consulted Sheldon Brown and various other sources and decided to go with the method of wrapping the chain around biggest chain ring & largest cassette cog and adding 1inch. Problem is that the chain came with a power link and it was not possible to break the chain at the exact size due to fitting of link. I was left with the dilemma of either adding half inch to the chain or 1 and half inches; either method allowed for powerlink to fit. I decided to go for the latter which left the chain half inch longer than required.
Everything seems to be OK, changing is good etc however, when running small chain ring on front and small cogs on back I can hear the chain rattling. Further web based searching has indicated that this is a sign of an overlong chain.

I was wondering what might be the implications of running the chain slightly shorter.

Additionally, yet not related to the above scenario, has anyone experienced any problems with using a 9 speed powerlink on a 10 speed chain.

Comments and suggestions gratefully received
Thank you

[Mick F]

I have the same situation, and I've erred on the side of "too long". All hell would break loose if it were too short!

I have a Chorus Triple with a medium cage. 53/42/30 and 13-29 cassette.

Little/Little

Big/Big


Mine works perfectly. Even when I'm on little/little the clearance is JUST enough to clear the cage. On big/big there's enough chain to work ok too. The medium cage is just sufficient for all of Campag's range and you only need a long mech if you want a bigger range cassette or a wider chainset.

I hope my photos help, but you MUST be able to get big/big even though you might never select that gear intentionally. One day or another you will get in that gear, and you need to know that it'll cause no problems.

[Mick F]

PS
Sorry, missed the bit about a 9sp Power link.

It would work, I reckon, though I've never tried it. I have tried a 9sp chain on my 10sp equipment as an experiment, and surprisingly, it worked! Not very well and a bit noisy, but it worked. Therefore a 9sp PL may be ok.

Why do you want to?

[sharpy]

Thanks for your sage advice Mick,
On the question of the powerlink there is no pressing reason as to why I might wish to use a 9 speed on a 10 speed chain; I just happen to have a few of the former lying around.

[CREPELLO]

Nine speed is a wider chain than ten, if not by much. But it may cause unpredictable chain noise or shifting.

[Mick F]

Nine speed is the same width as eight speed and is the same width as ten speed.
All derailleur chains are the same internal width.
(Don't know about 11sp)

The only difference in derailleur chains is the external width. It's the plate thickness that is different.

This mean that all derailleur chains and sprockets match easily, it just that the distance between the sprockets vary with respect to the speeds compressed into the same space. Consequentially, 10sp chains are less wide than 9sp and 8sp externally but they fit the same width sprockets. There is just enough room for a 9sp chain to work with a 10sp cassette.