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Changing Cassette

fraz167fraz167 Posts: 142
edited December 2007 in Workshop
Hi,

I currently have an 11 - 22 cassette which i plan to change for a 12 - 26/27.

Will have to do any adjustment to the gear mechanism after this change or should it just work with the new cassette?

Cheers

Fraser

Posts

  • nicklousenicklouse Posts: 50,675 Lives Here
    yes you will. and you should also fit a longer chain.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • scherritscherrit Posts: 360
    Also if you have many miles on the chain, the new cassette won't be absolutely "happy" working with the old worn chain. This unhappiness may manifest itself as sub-optimal shifting and/or skipping under load, possibly worse on the smaller sprockets.

    You may get away with not moving the stop screws or the cable tension (barrel thing-y) as the sprockets should be where the old ones were!

    Chain need to be longer, probably so all above is moot!
    If you're as fat as me, all bikes are bendy.
  • nicklousenicklouse Posts: 50,675 Lives Here
    Also if shimano the B screw will need adjusting.

    but as you do not say what mech.....
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • henderson_mkhenderson_mk Posts: 637
    this is quite interesting actually....

    i swapped over a back wheel this morning from the original 11-23 to a 12-27 and it all seems to be shifting fine and worling grand.

    am I missng something or doing damage to something or other I don't know about?
    ========================================
    http://itgoesfasterwhenitmatches.blogspot.com/
  • nicklousenicklouse Posts: 50,675 Lives Here
    if it is all good then do not worry.

    Oh and dont use the big and big combo. As if your chain is the correct length of your old set up you could rip your rear mech of in worst case or just find you can not shift out of the big big combo.

    Also if the rear mech has a means of adjusting the jockey wheels position in relation ot the cassette you may find it rubbing on the new big cog, IF it was set correctly for the old set up.

    there is a big difference between correctly and working well. But the both work...
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • henderson_mkhenderson_mk Posts: 637
    well thats very true actually... :-)

    and the big/big combo isn't quite as quiet as it should be and has a bit of the rubbage. so how would i go about sorting that? its a durace rear mech.
    ========================================
    http://itgoesfasterwhenitmatches.blogspot.com/
  • nicklousenicklouse Posts: 50,675 Lives Here
    Err you need to lengthen the chain as you have added a bigger rear cog.

    but it would be best to read the chain length setting info on Parktools or any other web site.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • henderson_mkhenderson_mk Posts: 637
    just checked it there and it seems the top jockey wheel isn't rubbing the big sprocket... so this should be ok i think.
    ========================================
    http://itgoesfasterwhenitmatches.blogspot.com/
  • araceraracer Posts: 1,649
    nicklouse wrote:
    Err you need to lengthen the chain as you have added a bigger rear cog.
    Not necessarily - that's only the case if you've sized your current one on just being ble to use big/big. However that's not necessarily the best way to size a chain on a road bike with a normal double - if you follow the Shimano recommendation you'll have a longer chain which should work with up to a 27 sprocket on big/big.
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