Gearing help - 29&q...
 

[Closed] Gearing help - 29"

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i can just about manage everywhere on 32 front / 11-36 rear on my 26".

will 26/38 front on 11/36 rear on 29" be comparable ?

i'm afraid i can't do the maths....


 
Posted : 12/12/2011 7:03 pm
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go to www.sheldonbrown.com and find out ๐Ÿ˜†


 
Posted : 12/12/2011 7:06 pm
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rough rule of thumb, 2 teeth difference from a 26 ratio to get a workable one for a 29er so for SS 32:16 becomes a 32:18. Given that spread of gears, you'll be fine


 
Posted : 12/12/2011 7:06 pm
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tried sheldon but he doesn't have the newer 36 tooth rear sprocket on 10 speed.......


 
Posted : 12/12/2011 7:14 pm
 Sam
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tried sheldon but he doesn't have the newer 36 tooth rear sprocket on 10 speed.......

You can enter whatever numbers you like!


 
Posted : 12/12/2011 7:17 pm
 bol
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I discovered that a 28 tooth smaller chainring was too big for me when trying to winch my RIP back up the hills yesterday. I'm going to go for a 24/38 when I can find someone whose got them in stock. Alternatively I could man up, but I fear it's too late for that.


 
Posted : 12/12/2011 7:25 pm
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bol - what rear cluster are you running ?


 
Posted : 12/12/2011 7:26 pm
 gee
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I drop down 2 teeth between 26 and 29. 36t single ring on the 26, 34t single ring on the 29.

GB


 
Posted : 12/12/2011 7:50 pm
 bol
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I've got an 11-36 on the back. Nothing impressively roadie.


 
Posted : 12/12/2011 8:03 pm
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32 front / 11-36 rear on my 26"

[url= http://www.sheldonbrown.com/gears/ ]Sheldon says[/url] that's around 23.1" to 75.6".

will 26/38 front on 11/36 rear on 29" be comparable ?

That gives a range of 18.8" to 89.8".


 
Posted : 12/12/2011 8:08 pm
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I use 32T front 11-36T cassette on the hardtail and 24/36T front and 11-36T cassette on the FS, which is better for longer days with lots of climbing.


 
Posted : 12/12/2011 8:16 pm
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Looks like I may stay 3*10 on Xtr trail instead of 2*10. Not too sure about sram Xo...


 
Posted : 12/12/2011 8:42 pm
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10% difference, that's all you need.


 
Posted : 12/12/2011 8:59 pm
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why 10% ?


 
Posted : 12/12/2011 9:21 pm
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29" is ~10" > than 26" so you just need to adjust things by 10% overall.

Were you out smoking during maths class? ๐Ÿ˜›


 
Posted : 12/12/2011 9:23 pm
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not too sure it's that simple however AL although i did suspect that was your angle.....

i think 26 front 36 rear may be too hard to spin up here in the highlands.......?????


 
Posted : 12/12/2011 9:37 pm
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if you can ride 32-36 on a 26" 26-36 on a 29er will be a doddle, you really are over analysing this you know ๐Ÿ˜€


 
Posted : 12/12/2011 9:44 pm
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why don't shimano do 2x10 ratio options on XTR like SRAM do on their chainsets ! ? ??? !!


 
Posted : 13/12/2011 9:48 am
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I think what you may find is that neither the 26 or the 38 are any good a lot of the time, apart from with 1/3 of the sprockets at the back - you may be better off with just a 30T up front?

10spd Shimano with a 2x SRAM or FSA chainset?


 
Posted : 13/12/2011 11:22 am
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jameso - i'm tending to agree.

i like shimano drivetrains - longevity and quality bits of kit.

never used SRAM drivetrains so have little experience of their quality TBH.

i want XTR or XO and XO is now winning due to the options they provide running 2x10.....


 
Posted : 13/12/2011 12:03 pm
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Seems a shame to ditch XTR just due to FC ratios, I'd just go for an FSA chainset for now, until there's some better Shimano options?(there's not for 2013 tho by the look of it)


 
Posted : 13/12/2011 12:10 pm
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10% is pretty spot on - yes, it is that simple.


 
Posted : 13/12/2011 12:37 pm
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may gamble on the XTR 2x10 running 26 front/36 rear. according to Sheldon, this gives 20.9 Gear Inches on 29" wheels.....


 
Posted : 13/12/2011 1:15 pm
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Yup, it is that simple, no idea how complicated your gearing system is though, real men ride singlespeed*

*I do not ride singlespeed, much.


 
Posted : 13/12/2011 1:17 pm
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singlespeed is available as a reserve [my old Hummer].... ๐Ÿ™‚


 
Posted : 13/12/2011 4:23 pm
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Simon, a suggestion: put yer old 10 speed xt on the bike for a start and see if you like it.
Try not using the grannie/bottom gears.
If you find you don't miss em go 2x.
If you find you need em get 3x.
Simple and I personally guarantee that this will work.
PS you will also be able to see if you are going to have pedal strike on 175 too!
A win win.
Anything else, feel free to ask...
๐Ÿ˜‰


 
Posted : 14/12/2011 5:30 pm
 tang
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Keep the triple cs and the fettle later with other rings. I have a 29er which I run 1x10 32/bash up front, 36 out back and I run it 26/38 for long days with the 38 in the middle I get full spread. Still have the triple ring set if need be.


 
Posted : 14/12/2011 6:00 pm