Shimano Cassette Installation Problem

Quoted post said:

Originally posted by jim.egan
Just purchased a climbing cassette for my 9spd ultrega set up. Installed the cassette on a set of wheels I've used for a long time but the gears seem to vibrate and are not smooth when pedalling. Has anyone experienced similar problems? What was the solution?

Wheels: mavic cosmos
Ultegra throughout.
New cassette: 12X27

Is the cassette tight on the cassette body?
Are all the required spacers in place?

Sometimes, even with all the required spacers, due to manufacturing toleralances, it may need an additional spacer.
You need to look and feel for a proper fit.

Is the vibration/grinding in all gears or only on the 25 or 27 cog? If it's on the 25 or 27 you might check to make sure the chain is long enough that it's not maxing out the deraillure.

Quoted post said:

Originally posted by txbuckeye
Is the vibration/grinding in all gears or only on the 25 or 27 cog? If it's on the 25 or 27 you might check to make sure the chain is long enough that it's not maxing out the deraillure.

It vibrates less on the 25 and 27 than the bigger gears, but there's still a noticable vibration. And the cassette is definitely on tightly enough. I've isolated the problem to this cassette, having put on my other cassette on the same wheel as a test.

Quoted post said:

Originally posted by jim.egan
I've isolated the problem to this cassette, having put on my other cassette on the same wheel as a test.

Same cogs? There is always the chance of a defective casette,but when going to bigger cogs,you have to have correct chain length and proper adjustment of the B tension screw.

Quoted post said:

Originally posted by boudreaux
Same cogs? There is always the chance of a defective casette,but when going to bigger cogs,you have to have correct chain length and proper adjustment of the B tension screw.

But then wouldn't the vibration only occur when on the cogs that are larger? In my case, the vibration is actually more pronounced in the cogs that match the cogs in my regular cassette.

I've read that the old chain might have worn down in parrallel with the original cassette. But I've only had the combination for about two years, 5 months of that I didn't even ride due to an injury. I guess it's possible that the old chain doesn't like the new cogs. But I would have thought that would take much longer to happen.

Some cassettes are extemely picky about chain stretch - as little as 0.5% elongation but you usually get skipping rather than noise.