Bicycle Mechanics - 12X27 instead of a 12X25? Will that work

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Nashville Man
11-17-05, 10:18 AM
I just bought a new set of wheels and I need a rear cassette as well. I'm looking at the 12X27 Ultegra cassette for these rims. My question is, if I have a 12-25 on my stock rims and switch to a 12-27, will I have to adjust my rear derailer everytime I swap my rims out? I plan on using my old rims on my trainer.


Grasschopper
11-17-05, 10:23 AM
You shouldn't have a problem that is caused by the cassette unless your pulleys are rubbing the now 2t bigger cog. My concern would be that the hub may put the cassette in a slightly different location which may effect your shifting.

Nashville Man
11-17-05, 10:25 AM
You shouldn't have a problem that is caused by the cassette unless your pulleys are rubbing the now 2t bigger cog. My concern would be that the hub may put the cassette in a slightly different location which may effect your shifting.

I never thought of that. What tools will I need to buy along with this cassette to do the work? Thanks for the help.


Grasschopper
11-17-05, 10:38 AM
I never thought of that. What tools will I need to buy along with this cassette to do the work? Thanks for the help.

Do you have the cassette lock ring tool? Other than that and a chain whip to remove a cassette (if/when you have to) you only need a philips head to tune the RD and that would only be if you need to reset the limits.

Nashville Man
11-17-05, 11:10 AM
Do you have the cassette lock ring tool? Other than that and a chain whip to remove a cassette (if/when you have to) you only need a philips head to tune the RD and that would only be if you need to reset the limits.

Will the Spindoctor whip that I've attached the link for work? It's $10 vs. a $20 Park tool one. I'm not sure what the difference is, other than price.

http://www.performancebike.com/shop/profile.cfm?SKU=14456&subcategory_ID=4203

Grasschopper
11-17-05, 11:18 AM
Will the Spindoctor whip that I've attached the link for work? It's $10 vs. a $20 Park tool one. I'm not sure what the difference is, other than price.

http://www.performancebike.com/shop/profile.cfm?SKU=14456&subcategory_ID=4203

That is exactly what I use. I have The Spin Doctor Team Kit (http://www.performancebike.com/shop/profile.cfm?SKU=16571&subcategory_ID=4218) from performance and it has had all the tools I have needed until this week when I needed to buy a Campy lockring tool.

The quality is lower than Park, this is true with just about all of the Spin Doctor tools, but they work fine. As mine wear out I am going to replace with Park but I haven't had to replace anything in the last year.

sydney
11-17-05, 11:19 AM
An old chain will work and is free.

Al1943
11-17-05, 03:06 PM
Should work fine unless there is something unusual or out of specs on one of the hubs that would change the chainline.
I routinely change wheels with 12-26 and 12-23 cassettes, no adjustments needed except to the computer sensor.

Al

Grand Bois
11-17-05, 06:02 PM
I just throw a rag on the cassette, grab it with my left hand and work the lockring tool with my right hand. It always works for me, but I only work on my own bikes and I don't overtighten the lockrings.

HillRider
11-17-05, 06:53 PM
Changing the cassette should have no effect on chainline or hub location unless one of the cassettes is defective. You may have to adjust the "B" screw to clear the 27T cog but you can leave it there if you go back to the 25. Be sure the chain is long enough to allow big-big with the 27T.