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Shimano cranksets - which one? M770 or M771


flubberghusted's picture

By flubberghusted - Posted on 22 December 2012

Is there a difference between the two?
M771's are on special at the mo so more inclined to get those.

Compatibility wise, currently running the following so just curious as to whether it will run on it.

Shift Levers SRAM X-9 Trigger
Front Derailleur Shimano LX
Rear Derailleur SRAM X.9
Crankset SRAM GXP1, 22/32/44 teeth
Bottom Bracket SRAM GXP 68mm
Rear Cogs Shimano XT M770 9 Speed Cassette
Chain Shimano Dura-Ace/XTR 7701 9 Speed Chain

StanTheMan's picture

The difference is the amount of teeth.

do your research I just did a quick google. M771 on wiggle is a 48/ 36 / 26 while the M770 is a more traditional set for Mtbiking. Its a 44/32/22
also check the length the crank is available in. Perhaps the M771 would be more suitable for a cyclocross set up? not 100 % sure but youre going to have to have some serious strenth to make those work in an all rounder Mountain bike.

pehaps it would work on a bike that does a lot of road comuting. your middle ring would be used for most off road riding like XC while the granny gear at least wouldnt make you loose ballance while riding on the 34 rear cog. Its a trade off. Its basically to maker you go faster. but you need to decide f you have the strenth in your legs or the type of riding you do. if youre into AM....dont even consider the M771 its most likely too big.

JFYI I ride a double 9 speed set up 42/26 front 32-11 back..... I race here & there. Its perfect for XC stuff but any serious uphill where the 3X9 guys get into thier granny gear....I get off. There is only 3 spots in my local area where that happens.....so for me its worth the trade off.

with the XT 770 rear cassette its available in 32/11 or 34/11 I'D BE going for the 44/32/22 at the front
with your Sram derailer you need to have the Sram shifter. Its all about the shifting ratios but the Cassete & crancks will be compatible with either.

flubberghusted's picture

Thanks mate.
Yeah I've researched that the gear ratios being different and slightly heavier.

But just wondering if anyone has had the experience of running the 771's and how much difference in performance it was. Translation, is it that much harder?
As I was thinking about shifting to just a double chain set

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