|rear cassette problem?||EricRG|
May 20, 2003 11:38 PM
|Two of the cogs on my rear cassette seem to behave as if they have dirt on them...sort of crunchy...and much worse going up hills/applying force. This occurs in both the big and little chainrings, but only when I use these two particular rear cogs, not any of the other ones. It started out as just the one cog, now the other is affected as well. They also happen to be the two cogs I use(d) by far and away the most frequently. Otherwise, I keep them well lubed and quite clean. I have inspected them and they don't seem to be bent or any more worn than the other cogs. Any ideas? Thanks.|
May 21, 2003 4:01 AM
|"Otherwise, I keep them well lubed and quite clean."
That sounds like an oxymoron... are you "lubing" the cassette or the chain?
I really don't understand your symptoms here- is this something you feel or hear?
Is it possible it is a chainline issue? Is it something that trim can fix?
May 21, 2003 4:09 AM
|they are worn out. If they are the 2 smallest cogs, then I'd say that they are almost definitely worn out. Unless you have some profile gauge to check them with, you can't really tell by sight.
Have you recently chainged the chain? Often times slightly worn cogs don't become apparant until a new chain is installed. Even slightly worn cogs will kill a new chain very quickly.
The other possibility is that the chain is simply worn, and it's only noticable in these 2 cogs (once again, betting that it's the 2 smallest).
How much elongation does your chain have?
May 21, 2003 8:25 AM
|Actually, they are the 2nd and 3rd LARGEST cogs. But I ride to work every day a flat 9.5 miles each way, so I used those two cogs by far the most. I did in fact recently get a new chain. I'm avoiding using those cogs at this point, but that means I'm riding in a gear that is a harder than I am normally comfortable with most of the time. Do you think I should replace the individual cogs (since the others are likely far less worn) or the entire rear cassette?|
|re: rear cassette problem?||ukiahb|
May 21, 2003 7:56 AM
|are the cogs in sequence and riveted to a commomn carrier?? I had a creaking problem w/ the 17/19 pair on my Campagnolo cassette caused by loose rivets and had to buy a new pair (from Branford Bike), though visually it looked fine. Have heard this is common w/ Campagnolo cassettes, don't know about Shimano.|
|Did you replace the chain recently?||LC|
May 21, 2003 9:00 AM
|A new chain would have exactly this symptom when on your favorite cogs.
I assume this is a 105 or lower cassette with individual cogs instead of a carrier? I would replace the entire cassette unless you already have some individual cogs laying around. I would also remove the cassette and look at the hub to see if it was damaged from the lockring not being tight enough.
|re: rear cassette problem?||arderra|
May 21, 2003 10:37 AM
|Are the two cogs on backwords????
That might be the problem. If they are on wrong then the grove in the cogs that allow smooth gear changing will be "bitting" the chain on each rotation and not allowing smooth gear change
|Are they loose? Check them by hand, if they moved then||Paul|
May 23, 2003 4:37 AM
|need to tighten up the lock ring. This is a common problem, and because they are not held on to the cassette by rivets or long screws, these higher gear cogs will loosen. |
One of theresponders mentioned about being on backwards, have you ever taken them apart? On Shimano, they are numbered, and this side will go on face up as you look at the cassette, of course they have a spacer between them.
If they were worned, you would get chain skip on these cogs.
If all else fails, buy a new cassette.