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Crank/Bottom bracket alignment/torque question.

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Crank/Bottom bracket alignment/torque question.

Old 07-15-13, 07:06 AM
  #1  
gitarzan
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Crank/Bottom bracket alignment/torque question.

I know there is an optimal torque for bolting on the cranks to the bb.

I do have a torque wrench but do not own a set of Allen adapters.

Anyway, what I want to know... Is should the crank be tightened to the point where the the end of the square bottom bracket be flush with the bottom of the cranks hole?

Much like this?

https://www.google.com/search?safe=o...JOhr3wTzSpM%3A

I would assume that that be a matter of alignment of the chain line, BUT I have done things that made sense to be before and don't want to bugger it up.

The reason I ask is that while I lightly greased the BB end the wrenching is getting firm. Since I don't have the proper torquing setup, I want to be sure I do not bust bolt or crack my crank.
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Old 07-15-13, 07:15 AM
  #2  
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Originally Posted by gitarzan View Post
I know there is an optimal torque for bolting on the cranks to the bb.

I do have a torque wrench but do not own a set of Allen adapters.

Anyway, what I want to know... Is should the crank be tightened to the point where the the end of the square bottom bracket be flush with the bottom of the cranks hole?

Much like this?

https://www.google.com/search?safe=o...JOhr3wTzSpM%3A

I would assume that that be a matter of alignment of the chain line, BUT I have done things that made sense to be before and don't want to bugger it up.

The reason I ask is that while I lightly greased the BB end the wrenching is getting firm. Since I don't have the proper torquing setup, I want to be sure I do not bust bolt or crack my crank.
Absolutely NOT - the pic does not show that, but rather a spindle end that is slightly below the level of the surface of the crank. That pic shows the closest you generally should see the end to the arm surface. Also it's not great practice to grease the spindle flats, as it encourages overtightening. After making sure the flats on spindle and crank are clean of contamination (with steel wool, for example) the residual oil on your fingertips is actually enough in my opinion.
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There's no such thing as a routine repair.

Don't tell me what "should" be - either it is, it isn't, or do something about it.

If you think I'm being blunt take it as a compliment - if I thought you were too weak to handle the truth or a strong opinion I would not bother.

Please respect others by taking the time to post clearly so we can answer quickly. All lowercase and multiple typos makes for a hard read. Thanks!
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Old 07-15-13, 07:44 AM
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Thanks. I'll go get a set of Allen's that will fit a socket tonight.
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Old 07-15-13, 08:53 AM
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Go buy the socket and torque the crank. Anything else is a gamble. It should be torqued to 25 pound feet.
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Old 07-15-13, 03:58 PM
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And next time don't gease the axle flats. This allows the arm to travel too easily up the taper. Andy.
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