I have a Trek Crossrip with Shimano Claris. Front mech is 3 x 8 with 50 / 38 / 30 teeth. I would like to fit a Shimano Alivio chain set with 48 / 36 / 26 teeth, would this be compatible ??

  • What's your goal? Are you looking for lower ratios in the smallest ring? – Argenti Apparatus Sep 10 '19 at 18:13
  • Also, do you know what size cassette you have in the rear? – Argenti Apparatus Sep 10 '19 at 18:19
  • If the Claris crankset uses a "standard" 74mm triple-crankset BCD for the smallest chainring, you should be able to just replace the one chainring with something smaller than a 30t. A 74mm BCD ring can go down to 24t, and would be a lot less expensive than replacing the entire crankset. – Andrew Henle Sep 10 '19 at 19:18
  • Do they have the same bottom-bracket mount? Square taper, octalink, etc ? – Criggie Nov 10 '19 at 3:34

You can most likely fit a MTB triple crank - if the bottom bracket shell is threaded you can fit a Hollowtech bottom bracket that works with 68mm shell with spacers or 73mm wide shell without spacers and accommodates the axle length of the Alivio crank.

However, you'll run into compatibility issues because MTB triple drivetrains use a chainline of 50mm, whereas road triples use 45mm.

Basically if you fit a MTB triple crank the chainrings will be 5mm too far outboard relative to the cassette sprockets which will make cross-chaining from large chainring to large sprocket very bad, likely give you shifting problems and front derailleur chain-rub issues.

  • I think the chain angle from large ring to small sprocket is going to be improved. What gets worse is large-large. – ojs Sep 10 '19 at 18:30
  • @ojs argh, I meant large sprocket of course – Argenti Apparatus Sep 10 '19 at 18:38

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.