SS 29er ratio???
 

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[Closed] SS 29er ratio???

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i just bought my first mtb (a very nice singular swift 29er). looks so good, but im already keen to convert it to a SS

its got a surly 36t chainring up front that i dont want to change. On other posts ive read 2:1 is a good gear ratio, so that would mean an 18t on the back. but is this the same for a 29er??

so my question is how many teeth should i run if i have a 36t chainring?

cheers


 
Posted : 10/10/2012 6:48 pm
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20


 
Posted : 10/10/2012 6:50 pm
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32:18 is 29er ~32:16 equivalent. 36:20 is about the same as that.


 
Posted : 10/10/2012 6:54 pm
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Depends on how fit you are, where you ride etc. 36:18 will be a good starting point, then fine tune if you find it too hard/easy. I started on 32:16 on my Swift before, eventually, settling at 34:18 as my 'sweet spot'


 
Posted : 10/10/2012 6:56 pm
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32:16 34:17 36:18

are they all the same??

also, so on a 29er im looking at 36:20 to start??


 
Posted : 10/10/2012 7:49 pm
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Mine's 32 X 18 ss, 32 X 16 fixed, nice............


 
Posted : 10/10/2012 7:51 pm
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OP, the answer was in the thread you started on SS ratios the other day )


 
Posted : 10/10/2012 8:00 pm
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32:19 here in the NW Alps


 
Posted : 10/10/2012 8:02 pm
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OK; a 2:1 ratio (eg. 32:16) is the starting point for a 26er. Because a 29er has a bigger wheel, each pedal turn will take you further for the same gear ratio, making the gear proportionally higher overall by 29/26 (because circumference is proportional to diam - with me so far)

Hence instead of 2:1, you want something slightly less as a starting point for a 29er.

32:16 x 26 = 52

32:18 x 29 = 51.6

or for you with a 36T front:

36:20 x 29 = 52.2

Now, if you want something slightly easier, because you live in a hilly area, or are a spinnier rider, then up the rear or reduce the front accordingly (not sure how easily available 21 or 22T rears are though). I doubt you want much harder unless you live somewhere properly flat like Thetford.

FWIW i run 34:18 x 29 = 54.7 but I have got a wonky ring on the front which is a whole different question

http://singletrackmag.com/forum/topic/elliptical-single-speed-chainrings


 
Posted : 10/10/2012 8:27 pm
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OP, the answer was in the thread you started on SS ratios the other day )

he doesn't make it easy does he

(I just did my maiden 29er SS ride, on 32:18, and I'm sure I found it a tad spinny compared to 32:16 on my SS, so may up the back to 17).


 
Posted : 10/10/2012 10:10 pm

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