New: Take part in the February 2020 BikeRide Giveaway for a Proviz REFLECT360 Cycling Jacket

Welcome guest! Register or sign in to participate in the cycling discussions.


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...
Thread Author Replies Views Last Post
  Replacing rear wheel after patching a flat munnikm 3 6,519 12-04-2015, 09:33 AM
Last Post: munnikm
  Replacing old rear derailleur eab 3 12,500 05-14-2015, 09:55 PM
Last Post: DaveM
  [Rear Derailleur] Gears up/down by one cog Infocus 2 4,427 02-09-2015, 05:19 AM
Last Post: budstutor
  I can only use the highest 5 gears on my 8spd rear cog bianchi29er 21 26,852 09-01-2014, 09:35 AM
Last Post: wikey
  Replacing a rear axle with a quick release ConfusedMonkey 8 17,553 06-02-2014, 12:25 PM
Last Post: cny-man
  Free wheel cog? Ricardocast95 1 3,410 07-25-2013, 10:14 AM
Last Post: DaveM
  Rubbing on second smallest cog gecici90 14 13,107 05-17-2013, 03:40 AM
Last Post: Bill
  Changing from 16T Profile Rear cog to Profile Elite freewheel Jen 1 4,375 10-07-2012, 02:30 PM
Last Post: Bill
  Welding fixed cog to hub eorta7 10 13,956 05-06-2012, 12:02 PM
Last Post: Joe_W
  Changing cog set cyclepatty 3 6,905 04-11-2012, 07:50 AM
Last Post: Joe_W

Forum Jump: