Convert Shimano M-590 3x10 to 2x10

obrir3

Hi All,

This is my first forum post (so be gentle :?), and I know there are already heaps of questions about 3x10 to 2x10 conversion on here, but I can't find an answer to my specific question:

My current setup is 3x10 with a Shimano Deore FC-M590-10 crankset (42/32/24 rings) and SLX shifters / front derailleur. I want to convert to 2x10 and change the middle ring to 36t as I hardly ever use the big ring.

My question is this - I've found a 36t Shimano ring on CRC - http://www.chainreactioncycles.com/shim ... -prod83369 but it specifically states it's for the 9spd variant of the M590 crankset; so I'm not sure if it's compatible with my 10spd cranks? (I've also asked this question on CRC but thought I'd tap the inifinte pool of wisdom on BikeRadar as well!).

If not (or even if it is) would I be better going with a chainring from someone like Blackspire instead? (I'm thinking of getting a Blackspire bash ring).

Thanks in advance!

supersonic

Can be a minefield! 10 speed rings are narrower and are designed to be closer together - but the offset can be in the ring or spider. It will work, but you may need to file the spider or chainring for optimal results.

obrir3

Hi supersonic,

Thanks for the reply. I feared that might be the case ... it's fairly cheap on CRC so might just buy it and give it a go.

P.S. apologies for slow reply - seems I forgot to check the 'notify me when reply is posted' box!

Thanks

jimothy78

I've said it before and I'll say it again:

If you're changing to 36T/22T teeth at the front it's definitely worth sourcing one of the SLX M665 double-specific front mechs - so much better than just an adjusted tripple mech - Much easier to set up without any rubbing, and better chain retention too.

obrir3

Makes sense ... although isn't the M665 2x9 specific? So something like the M675 would be better?

jimothy78

obrir3 wrote:

Makes sense ... although isn't the M665 2x9 specific? So something like the M675 would be better?

Looks like that one can take up to a 44T chainring, so it won't have the same optimised shape for a 36T ring as the 665 (which is designed specifically to go with a 36T/22T double and works perfectly well with 10sp setups anyway).

I might be wrong, but just double check as if the cage is too long or straight you can't drop it close enough to the BB - that's the limiting factor more than anything...

obrir3

Thanks for your help ... I'll look into it. The last thing I want to do it mess up the shifting so for now I might just keep my setup as it is, this might be a project for 2014 I think!

Thanks again