Have questions or want to discuss cycling? Join Now or Sign In to participate in the BikeRide community.

New: Take part in the July Giveaway for VTUVIA SN100 Camouflage Fat Tire E-Bike $1679


Replacing rear cog
#1
Hi all,
I have a shimano ultegra 6600 12-25 cassette (and deralieur).
I would like to add a lower gear - a 28 if possible.
I know shimano make a 6700 11-28 ultegra 6700 but AFAIK this isnt supposed to work with the 6600 setup.
Has anyone tested this?

Also, is it a viable option to just buy a new cog or 2 (say a 24 and a 28 and replace the 23 and 25)? Any 'gotchas' with this idea (e.g. deralier wont work with 28T, the jump is too big, or are the cogs locked together etc)

Many thanks,
Sean
  Reply
#2
Hi

You cannot change individual cogs, You need to replace the entire cassette. I think your set up can handle extra three teeth without problems. Just may need to tune the rear deralieur. Cassettes are not expensive.

Your photo shows a MB but 25T is short for MB so you must be doing a RB. Some info on bike is always helpful. On a MB you can put a smaller granny gear.


bikeride.com/replace-cassette-cluster/
Never Give Up!!!
  Reply
#3
hi, thanks for quick reply,
sorry - thats my old bike in the photo-
my new one is a Cervelo S1 - Road bike.
  Reply
#4
Yes, 10-4 to that. Its not a major swap check out how to in repair guide and the link I send. The chain may get short but I doubt it.
Never Give Up!!!
  Reply
#5
Check your chain length with the new cassette installed. may need a link or two? Just set up the derailleur as if it was new. Check the limit screws to make sure there wasn't any spacing differences after the cassette swap. Should be all good to go.
GO RIDE...
  Reply


Possibly Related Threads...

Forum Jump:

[-]
10 Latest Posts
Cycling photos while on holiday
Yesterday 05:35 PM
Help identifying date of manufacturing
Yesterday 10:23 AM
Make a freewheel removal tool
Yesterday 07:32 AM
Weak spring tension on the derailleur wi...
Yesterday 07:18 AM
Woodsplitter in Pittsfield, Vermont
08-12-2022 06:19 AM
New Stator For My Ride1up Core 5
08-10-2022 08:49 PM
Jumps a Gear
08-09-2022 07:14 PM
Rode my First Double Century in June
08-08-2022 11:42 PM
2022 road cycling season
08-08-2022 04:03 PM
Vairas vintage bicycle brand
08-08-2022 11:45 AM

[-]
Join BikeRide on Strava
Feel free to join if you are on Strava: www.strava.com/clubs/bikeridecom

[-]
Top 5 Posters This Month
no avatar 1. ichitan
21 posts
no avatar 2. ReapThaWhirlwind
17 posts
no avatar 3. Jesper
16 posts
no avatar 4. dinh thaihoang
11 posts
no avatar 5. Criminal
7 posts