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First off, what torque difference is there between 170 and 175 or 180 mm crank length. Would I be able to feel the pedaling difference so much as I would tire out from more revolutions with the shorter cranks? I will be the first to admit I am out of shape but they feels much more draining than my other cranks. Granted these are on a titus motolite and the other are on a specialized hardrock. I don't know how much travel stiffness I was losing.

Okay, so as we were examining the bike after yesterday's short ride, my first trail ride on this bike, we discovered a bit of lateral play in the cranks. There appears to be too much spindle length. Even after repeated tightening,loosening, greasing and tightening to torque, we could not get the arm to come in against the bearing seal. It all felt good on set up but we realize that we were fooled by the way that the right side seats in its bearing. The directions said it may need repeated tries but how many. It seemed that the torque wrench was stopping at the right place.

Also, when we have the left side off it is easy to feel a lot of end play in that side of the spindle, like it is too small a diameter for the bearing.
Are there any spacers we should be using or could there be compatibility issues between those arms and spindle and the bottom bracket? I think it's an XT BB.

The cassette is an Shimano XT 11-34. I was wondering if the gearing could be different than I'm used to also. I don't know how much difference there is in ratios using different cranksets. The granny gear seemed like I was pedaling with no chain. Some of this could be getting used to a new bike.

p.s. This is an xs motolite and I am 5'1'' if that makes any differenc.
 

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Also, when we have the left side off it is easy to feel a lot of end play in that side of the spindle, like it is too small a diameter for the bearing.
Are there any spacers we should be using or could there be compatibility issues between those arms and spindle and the bottom bracket? I think it's an XT BB


Kriz,

Shimano outboard bearings are NOT compatable with Truvative cranks (different diameter). If this is indeed your setup, change back to the GXP to fix the problem.

If however you do have the correct bb in your bike (GXP) and have play, it might be due to your spacer configeration, or lack of. Any chance you have a 68mm bottom bracket shell? If you do, check to see if you have one 2.5mm spacer on each side of the cups. If you are missing any, this would be the cause of your problems because as you tighten down the crankarm it stops on the spindle before it are able to preload the bearings = play

Re: crankarm length. I would suggest a 170mm arm because of your height - you don't have a long leverage arm (legs) to turn over a 175mm very smoothly/efficiently. Talk to Titus, or have a shop, who has a fit kit, to PROPERLY size you
Good Luck
 

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Same Issue

I had the exact same thing hapen to me when I was installing a Truvative Stylo BB and crank. I would torque the non drive to spec but it would be no where near close to where it needed to be (up against the bearig seals). It's like the 45 ft/lb spec isn't enough to actually screw in the crank all the way. I just ended up cranking that SOB down. Besides depending on how you interepret the install instructions it says something like: tighten to torque. If play is felt tighten until there is no play. If maximum torque (AKA if you can't tighten it any more) is reache and there is still play remove, grease, and re-install. At least thats how I see it.
 
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