John Eliastam Posted November 10, 2017 Share I've got a Cannondale Rush 1 with 38 / 24 chain rings up front and an 11 / 36 cassette. I'd like to go slightly bigger up front, maybe 40 /26. The bike has a Deore Hollowtech crank. Will this work? Common sense says that I would just need to life the front derailleur a bit, but common sense has it's limitations.... Any suggestions? The guy at Chris Willemse Cycles told me I'm stuck with a 38 up front and an 11 at the back as my best ratio - or I need to buy a road bike! Bonus 1 Link to comment Share on other sites More sharing options...
Robrider Posted November 10, 2017 Share I did exactly this with an xt crank. I don't think there should be an issue, as long as the difference between the rings stays the same. Check the clearance on the frame of the small ring. The bigger small ring runs quite close to the frame, but there is space. If your frame is different this may be an issue. Link to comment Share on other sites More sharing options...
John Eliastam Posted November 10, 2017 Share I did exactly this with an xt crank. I don't think there should be an issue, as long as the difference between the rings stays the same. Check the clearance on the frame of the small ring. The bigger small ring runs quite close to the frame, but there is space. If your frame is different this may be an issue.What type of chain rings did you use? With Shimano I can only find a 42 / 28 combo, and I'd prefer 40/26. I've seen some FSA chain rings that are the right size, but heard mixed reviews about how they shift Link to comment Share on other sites More sharing options...
droo Posted November 13, 2017 Share Depends on your FD mount. If it's direct mount you may be limited to a maximum size with your current FD, but should be able to fit a new FD for a bigger chainring. Besides that the only thing that should limit you is chainstay clearance. Link to comment Share on other sites More sharing options...
Robrider Posted November 14, 2017 Share What type of chain rings did you use? With Shimano I can only find a 42 / 28 combo, and I'd prefer 40/26. I've seen some FSA chain rings that are the right size, but heard mixed reviews about how they shift I run XT stuff, so I used these, think I went 28-40: https://www.cwcycles.co.za/product/shimano-xt-785-chainring-40t https://www.cwcycles.co.za/product/shimano-xt-785-chainring-28t Link to comment Share on other sites More sharing options...
Kona Kula Posted November 14, 2017 Share So, it depends on a few things. First what size is you bolt circle diameter. You will need to check that first. Second, some chainrings are designed to work together, you will see an AJ, AK or an AN etc You need to match these with the smaller ring for optimal shifting. They are designed to work together. What Bob the builder has posted above is the AJ combo and would work together. a 38/26 combo would be AK, and AM is a 38/24 combo. Link to comment Share on other sites More sharing options...
johanpre44 Posted November 14, 2017 Share I used to have a 38/24 but replaced with a 38/26 when it wore out. The location of the shifting pins on the big ring is slightly different. I would also like to go a little bigger but honestly don't see the point in going to a 40t, will only make a 2kmh diff when running it on the 11t at a cadence of 90 (43kmh on the 38t and 45kmh on the 40t). Not too fond of a triple, so I think I will stick to the 38/26 which I think shifts a little better than the 38/24. Link to comment Share on other sites More sharing options...
Kona Kula Posted November 15, 2017 Share I used to have a 38/24 but replaced with a 38/26 when it wore out. The location of the shifting pins on the big ring is slightly different. I would also like to go a little bigger but honestly don't see the point in going to a 40t, will only make a 2kmh diff when running it on the 11t at a cadence of 90 (43kmh on the 38t and 45kmh on the 40t). Not too fond of a triple, so I think I will stick to the 38/26 which I think shifts a little better than the 38/24.I agree with you. I am running a 40/28 with a 40-11 cassette. I would actually prefer a 38/26 as i like the 40-11 cassette spacing and the extra speed is never really necessary. Link to comment Share on other sites More sharing options...
s14phoenix Posted January 17, 2018 Share I agree with you. I am running a 40/28 with a 40-11 cassette. I would actually prefer a 38/26 as i like the 40-11 cassette spacing and the extra speed is never really necessary. except if you are riding at Modderfontein or Avianto and then 65kmh+ on the downhill sections is great for passing loads of lower geared spunouts Bonus 1 Link to comment Share on other sites More sharing options...
Bonus Posted July 2, 2018 Share except if you are riding at Modderfontein or Avianto and then 65kmh+ on the downhill sections is great for passing loads of lower geared spunouts I miss my Triple for this very reason! Link to comment Share on other sites More sharing options...
seanrcb Posted July 3, 2018 Share I'm busy with exact same installation bought FSA rings at CWC 40T FOR R50 new 11-36 cassette and chain going onto old Scott Genius MC 50 with E-type derailleur everything appears to fit and clear properly waiting for LBS need to get new gear cables to check function - Holding Thumbs Bonus 1 Link to comment Share on other sites More sharing options...
seanrcb Posted July 3, 2018 Share Success fitted 40t chain ring with my deore FD E-Type all running smooth Link to comment Share on other sites More sharing options...
seanrcb Posted July 3, 2018 Share Small gap between big ring and chain stay Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now