|Having some chain rub. Will using a 10 spd chain help?||Gerbila|
Sep 28, 2003 7:48 PM
|I have a Ultegra 9 spd double setup. With the Shimano HG-93 chain in the small ring in front, I get slight chain rub in the 13T cog, and major rub in cogs 11T and 12T. It's really limiting my intermediate gear selection. The chain is not rubbing on the front derailleur, but actually on the large chainring. I was wondering if switching to a narrower chain, like the Campy 10 spd, would possibly solve my problems, and have any adverse effects? Has anyone here tried this? Thanks.|
Sep 28, 2003 8:16 PM
|The Campy 10s chain has a smaller inside dimnesion then 9s, so it may not even run on 9s cogs. Narrower chains are always harder to deal with than wider chains. 39X11 is almost exactly equal to 39X15, and the other combinations are within 5% or so, even closer if you have a 16T cog. You could try a longer BB axle to change the chain line a little, but a narrower chain will only make front shifting worse and be more failure prone.|
Sep 29, 2003 5:25 AM
|You are correct that the slightly narrower chain won't cure this problem, but it's widely know that the Campy 10 chain will work fine with the Shimano 9 crankset. Lots of folks have converted from shimano 9 to a Campy 10 setup without changing the crank or front derailleur.
Also the cog nominal cog width on Campy 10 and Shimano 9 are within .001 inch of one another. For all practical purposes, they are identical. There is no cog width problem.
The poster did not state the type of crank and BB being used, but the obvious first step is to verify that the crank and BB spindle length are correctly matched. With the newer octalink BB, there really are no slightly longer spindle lengths available. If the crank and BB are properly matched, then the chainline should be checked for accuracy. If it's OK, then it's just something would have to live with. It's quite possible that there is nothing wrong at all.
|not quite....||Rusty Coggs|
Sep 29, 2003 6:43 AM
|besides making sure the 39 ring is mounted correctly with the 39 facing the BB, other options are a longer XTR spindle BB or a BB spacer. A 10 speed chain is a bit narrower and will work, but may not be narrow enough to solve the problem.|
|Assuming all else is right, use a BB spacer||Kerry Irons|
Sep 29, 2003 5:26 PM
|You can get a spacer to move the right BB cup out. That will shift your chain line so that you don't get the rub in the 13, and maybe the 12. Two spacers would likely let you use the 11, though that could be problematic due to chain slack. Things might not work as well in the larger cogs after this. Most accept that the small-small combination will not work. Then there's the question of why you need an 11 (41 mph at 110 rpm) but we'll let that go.|| |