Is it possible for my bike that I'm using Shimano Claris 11-28t 1x8 speed to upgrade my cassette in 11-34t 1x10 speed? Thanks. hoping for a good advice.

  • 1
    yes. you'll definitely need to upgrade your shifter as well and i believe your derailleur also
    – Paul H
    Oct 13 '20 at 18:28
  • you should give more details. Claris flat bar shifters or drop bar? what chainring do you have? which derailleur is fitted (model number and code)?
    – thelawnet
    Oct 13 '20 at 21:38

No. You cannot use a 10 speed cassette with an 8 speed derailleur and shifter.

Cassettes with increasing numbers of sprockets have narrower sprocket spacing, to allow the larger numbers of sprockets to fit on the hub. Shifters and derailleurs for different drivetrains with different numbers of sprockets are designed to move the derailleur cage the proper distance for each shift. Higher speed chains are also incrementally narrower to work with the narrower sprocket spacing. The chainrings are also more narrowly spaced to work with the narrower chain.

If you want to upgrade to 10 speed, you need a new cassette, derailleur, shifters and chain (and crankset if you were running a 2x setup). This is very often not cost effective vs simply buying a new bike with an upgraded drivetrain.

  • 1
    the 8-speed derailleur will work with a 10-speed chain and a 10-speed road shifter that's not 4700 or GRX (i.e. an old 10-speed shifter, not a current model). it's often not all that expensive, if you need to replace a worn-out chain & cassette, to update the shifters at the same time, but that would depend on whether the OP has flat bar or drop bar shifters
    – thelawnet
    Oct 13 '20 at 21:44
  • SHIFTER(S): Shimano, trigger, 1x8 spd REAR DERAILLEUR: Shimano Claris CRANKSET: Kitt Custom, Black Naked, 44T CASSETTE/FREEWHEEL: Shimano 11-28T, 8 spd this is my transmission specs and i watched also some videos that its possible to do upgrade from 8 speed to 10 speed.. how about if i use only 11-28t 10 speed cassette.. and just replace also the chain?
    – Robert
    Oct 14 '20 at 0:12
  • @Robert: How are you going to shift through 10 speeds with an 8 speed shifter? You’ll need a shifter as well and I doubt a narrow 10 speed chain is going to work correctly on the rear derailleur (not sure about the chainring either).
    – Michael
    Oct 14 '20 at 8:20
  • Okay thanks a lot.
    – Robert
    Oct 15 '20 at 10:36
  • Claris derailleur is a road derailleur and continues to have the same actuation ratio of all of Shimano's 7, 8, & 9 speed & 10 speed road derailleurs. Thus the Claris derailleur can be preserved. The Claris model RD-R2000 has a top low sprocket max tooth count of 32 (SS cage) or 34 (GS cage). Because of Shimano's conservative limit specs, it's likely either cage set up will work with an 11-34t cassette. A ten speed road (except Tiagra 4700) shifter will be required for proper shifting.
    – Jeff
    Oct 15 '20 at 23:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.