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Do it for Deegan
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Discussion Starter · #1 ·
Its a external BB 2 piece crankset and everything is solid except after tightening the crank arm bolt it still had about 1/2-1mm of left to right play in the crank. One thing that I thought was weird was that the crank didnt seem to come with a crank arm bolt so I just used one from my old crank but after everything was really tight it still had play. I have the right spacers on the BB to fit my 68mm shell too so were did I go wrong?
 

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check your six
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Couple of questions:

Are these a new set of cranks and what kind?

How many spacers do you have on each side of the BB?

I have had times where I needed three BB spacers on the non drive side and 2 on the drive side. As long as your chainline is not wacked out and it shifts well there will be no problem adding another spacer (to the NON drive side). It seems this will fill your 1-2mm space and movement.
 

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check your six
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where do i get a spacer? it only came with the three

Hmm.. best bet it to run to your LBS and ask the tech if he/she has any spare spacers laying around. I know I have a small box of them on my workbench from takeoffs and left overs. I actually enjoy it when a customer comes in and asks for small bits like this. It helps me clean out my work area from all my hoarding.

Otherwise here are a few links:

Bottom Bracket Spacer | eBay

Bottom Brackets and Adapter Kits from the best brands on sale now.[*+TO+10]

For me, I usually always run 2 spacers on each side of the BB with the occasional third spacer. And that goes for 68mm - 83mm cranksets.
 

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Is "really tight" something you felt like when tightening the bolt with a small L-shaped allen key, or did you use a proper wrench with a long handle, or even better, a torque wrench?
 

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The Original Suspect
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In my experience with RaceFace cranks is that they come with a crank arm bolt for the drive side and that bolt has a washer on it that will prevent over tightening. In fact I think the instal directions that come with them say to tighten till it stops. You may not have it tightened enough.

Race Face
 

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Do you have the rubber washers between the cranks arms and the bearings?
 

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Do it for Deegan
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Discussion Starter · #10 ·
Do you have the rubber washers between the cranks arms and the bearings?
No? I didnt install any washers or spacers other than the ones for the BB cups mainly because I didint notice any that came with the crank set. Its a very minimal amont of play but it isnt rock solid which is what it should be
 

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My RF Atlas crank had rubber washers that went on the spindle. IIRC 1 on the drive side and one on the non drive side that kept everything nice and snug. Mine came on a bike I bought 2nd hand and had a extra BB spacer in it instead of the rubber washer's. When I realized it was wrong I did some checking and found out about the rubber spacers, removed extra BB spacer, installed proper rubber washers and it was perfect.
 

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Do it for Deegan
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Discussion Starter · #12 ·
My RF Atlas crank had rubber washers that went on the spindle. IIRC 1 on the drive side and one on the non drive side that kept everything nice and snug. Mine came on a bike I bought 2nd hand and had a extra BB spacer in it instead of the rubber washer's. When I realized it was wrong I did some checking and found out about the rubber spacers, removed extra BB spacer, installed proper rubber washers and it was perfect.
Well I believe all the spacers and washers came pre-assembled on my crank from what I was reading on the instructions. Do you have a link to anything more about these rubber washers?
 

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Ride Instigator
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What you need is this 1.016mm (thick) shim that I'm holding in my hand. The shim goes on the crank spindle up against the non-drive side crank arm, the ID fits snugly on the crank spindle. This shim was left over from a retired RF Atlas crankset and should be the solution to your play issue. PM me with your mailing address and I'll send it to you if you want it.
 

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One thing that I thought was weird was that the crank didn't seem to come with a crank arm bolt so I just used one from my old crank but after everything was really tight it still had play. I have the right spacers on the BB to fit my 68mm shell too so were did I go wrong?
I agree with Hitmen, the bolt should be at a complete hard stop. I've installed a few of these, my main 2 rides and my wife's all have RF X-type cranksets and BBs. The bolt should come to a complete stop. The sets come with 3 spacers, one to use on either side for a 73mm, the third would go on the drive side for a 68mm BB shell. Since you are using a bolt from an older set, I wonder if perhaps the bolt is not the right length? If it is, then I would check to make sure the bolt is tightened to a complete stop. I did not use a torque wrench and IMO I don't think it is necessary unless you have a habit of over tightening everything or you have carbon parts. In this case, since the bolt comes to a complete stop why do you need a torque wrench?
 

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l shaped... but it was still pretty freaking tight
A regular L-shaped allen key has such a short lever that you'll be at a finger-hurting white-knuckle level of effort and still not tight enough. I know this from experience: out of curiosity I tried to get some bolts to torque with those things and I put my best effort in it. Then it was time to test how far I got - a torque wrench turned the bolt further before clicking.

Lesson learned: leverage. You need it.

This doesn't exclude other possible reasons, but is definitely something you might want to address.
 
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