marktmnt

I'm thinking of upgrading my 10 speed 11–38 rear cassette to a 10 speed 11–42, or higher. I'm looking at the Sunrace MX3 11-42. I have a 2014 Cannondale Scalpel with Shimano XT.

Has anyone done this?
How well does it work with the existing derailer & shifter?
Will I need a new shifter?
Will I need a new/longer chain?
Any words of advice before moving forward with this?
Any recommendations on a successful 11-42 good cassette change, besides the Sunrace MX3?

sch

Better idea would be an 11 spd 11-42 cassette, a drop in replacement without any of the potential
mess of dealing with the 11 spd shifter on a 10 spd cassette. Be best to add 1-2" to the chain
depending on how the RD cage angle looks with the 42.

Whoops, confusion of 11spd versus 11t cog.........

The Sunrace should be a dropin replacement for your present setup with the chain provisos mentioned.

marktmnt

I'd love to go to an 11 speed. But, that's not in the budget (new hub/wheel, new shifter...).

cpach

I think the 10 speed plan is fine, but for mountain 11 speed you do not need a new wheel. Just new shifter, derailleur, cassette, and chain. 11 speed mountain cassettes dish the big cog in towards the spokes to use the same freehub body as 10 speed--this is only possible if the big cog is 34t or larger approximately.