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[Closed] New 20 speed shimano drivetrain options help please!

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[#5965536]

I am after some help with choosing a new 20 speed drivetrain for my five spot.

I'm currently running deore 30 speed with a long cage rear mech.

I am looking at going 2 x 10 using slx stuff and have a few questions.

Which slx cassette would be best? 11-34 or 11-36?

Which rear shadow plus rear mech? sgs or gs?

Can I use my existing triple front mech and shifter on a double chainset?

Are there different chain ring options abate on a double chainset? If so what's best?

Sorry for all the questions I just want to make sure I get the right stuff!

Cheers

Steve


 
Posted : 16/02/2014 6:44 pm
 mboy
Posts: 12651
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"Best" is highly subjective. What's better for me may not be better for you.

FWIW, I'm of the opinion that there's no point in not having 11-36 on a 10spd cassette on a mountain bike. 11-32 and 11-34 just means slightly closer ratios, but seeing as an 11-36 10spd is spaced the same (in ratio terms) as an 11-32 9spd anyway, it would be of no benefit but the extra ratio span generally is, especially on a 1x or 2x setup.

Triple front mech will work with a double ring setup, but not quite as well as a double specific.

Front shifter will be fine, you just only get 2 of the 3 clicks.

For most riders a 26/38 double with 11-36 cassette is more than adequate. If you live somewhere particularly hilly, you may want to gear down to 24/36, or if it's quite flat up to a 28/40 or even 30/42 setup up front.

As for the rear mech. "Officially" the SGS can only deal with a max 35T overall difference (meaning 11-34 on a 26/38, but no 11-36 unless you had 26/36), but in practice it's ok on a hardtail with 37-38T overall difference in my experience. On a full sus bike though I'd run the GS because of chain growth.


 
Posted : 16/02/2014 6:52 pm
Posts: 7373
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Ok cheers

How do I set up a triple front shifter to work properly with a front double chainset?


 
Posted : 16/02/2014 7:47 pm