I just replaced my 12-23 Ultegra cassette with a 12-26 SRAM cassette ( I moved to the mountians and I'm too big a wuss to turn over the 23 on some of the climbs around here).
On the Ultegra, I only got chain rub on the big gear in the 39-12, but on the SRAM, i get rubbing in the 39-12,13,14 (or is it 15, either way its the 3 smallest cogs). I also replaced the chain with the new cassette.
Is it possible that changing the make of the cassette altered my chainline? If so, what's the solution (ignore, BB spacer, re-space the hub, buy a Shimano cassette)?
Try adjusting the derailleur out just a little .Its hard to believe that the cassette is wider than your original.but problem is .So I would try the adj screws a couple turns and see what happens.
Try adjusting the derailleur out just a little .Its hard to believe that the cassette is wider than your original.but problem is .So I would try the adj screws a couple turns and see what happens.
I think he's saying the chain is rubbing on the big chainring, not the front der. Adjusting the der will have no effect on that.
Originally posted by ejcookso I just replaced my 12-23 Ultegra cassette with a 12-26 SRAM cassette ( I moved to the mountians and I'm too big a wuss to turn over the 23 on some of the climbs around here).
On the Ultegra, I only got chain rub on the big gear in the 39-12, but on the SRAM, i get rubbing in the 39-12,13,14 (or is it 15, either way its the 3 smallest cogs). I also replaced the chain with the new cassette.
Is it possible that changing the make of the cassette altered my chainline? If so, what's the solution (ignore, BB spacer, re-space the hub, buy a Shimano cassette)?
Ted C.
I doubt that the cassette is at fault... it can only change the chainline slightly by moving in or out on the cassette body. However, if it is a few .1s of a mm wider than your previous casette, it will want the chain to be further out... and this does change the angle of the chain slightly. Cassette bodies and cassettes each have manufacturing tolerances. Some cassettes and cassette bodies are oversized or undersized. You may be dealing with an oversized cassette. Since you also replaced the chain, I would focus on the details of the outer dimensions of the chain itself... especially compared to what you had before. There are differences in the outer dimensions of various chains. Cross chaining in the gears you are talking about should be avoided. You should be able to get close to the same effective ratio without cross chaining.
Try adjusting the derailleur out just a little .Its hard to believe that the cassette is wider than your original.but problem is .So I would try the adj screws a couple turns and see what happens.
I think he's saying the chain is rubbing on the big chainring, not the front der. Adjusting the der will have no effect on that.
Art Harris
Yes, its the big ring thats rubbing. The deraillieur would've been easy.
I don't think this has anything to do with thew new cassette. I have used SRAM road cassettes for a few years now and it is my experience that they are identical in width and alignment on Shimano splined wheels. I honestly suspect that with a new, rigid chain, your chain line is more direct (chains get sloppy side to side with wear too), and that once the chain breaks in, you will get at least the third cog in and perhaps second over time. I notice this every time I put a new chain on and it clears up after about 300 miles.
Good luck!
Terry
daveornee said:
ejcookso said:
I just replaced my 12-23 Ultegra cassette with a 12-26 SRAM cassette ( I moved to the mountians and I'm too big a wuss to turn over the 23 on some of the climbs around here). On the Ultegra, I only got chain rub on the big gear in the 39-12, but on the SRAM, i get rubbing in the 39-12,13,14 (or is it 15, either way its the 3 smallest cogs). I also replaced the chain with the new cassette. Is it possible that changing the make of the cassette altered my chainline? If so, what's the solution (ignore, BB spacer, re-space the hub, buy a Shimano cassette)? Ted C.
I doubt that the cassette is at fault... it can only change the chainline slightly by moving in or out on the cassette body. However, if it is a few .1s of a mm wider than your previous casette, it will want the chain to be further out... and this does change the angle of the chain slightly. Cassette bodies and cassettes each have manufacturing tolerances. Some cassettes and cassette bodies are oversized or undersized. You may be dealing with an oversized cassette. Since you also replaced the chain, I would focus on the details of the outer dimensions of the chain itself... especially compared to what you had before. There are differences in the outer dimensions of various chains. Cross chaining in the gears you are talking about should be avoided. You should be able to get close to the same effective ratio without cross chaining.
9s chains vary a little (6.2-6.8) but is it possible that your new chain is noisier? I use the cassette you mention with much satisfaction. (Sram 89R hollow pin 6.2mm) Tom -- Bruni Bicycles "Where art meets science" brunibicycles.com 410.426.3420 dvt <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
Quoted message said:
I just replaced my 12-23 Ultegra cassette with a 12-26 SRAM cassette. >
On the Ultegra, I only got chain rub on the big gear in the 39-12, but
Quoted message said:
on the SRAM, i get rubbing in the 39-12,13,14 (or is it 15, either way its the 3 smallest cogs). I also replaced the chain with the new cassette.
I don't see how it's possible that a new cassette would change your
chainline
Quoted message said:
by 2 whole gears (9-10 mm). Something else must have changed.
