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My crank arm fell off while riding

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My crank arm fell off while riding

Old 07-03-08, 09:26 AM
  #26  
Landgolier
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This is a fine application for blue loctite or even just teflon tape.

Bonus points for the physics junkies: Does this generally only happen on the left because of precession, or does lateral force from the chain prevent excess squirm on the drive side? State your proposed test methodology.
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Old 07-03-08, 10:15 AM
  #27  
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Originally Posted by Landgolier View Post
This is a fine application for blue loctite or even just teflon tape.

Bonus points for the physics junkies: Does this generally only happen on the left because of precession, or does lateral force from the chain prevent excess squirm on the drive side? State your proposed test methodology.
On new cranksets it happens on whichever side isn't attached to the hollow axle

on BB's with a solid axle (octalink, ISIS, etc) I think the chain tension probably eliminates some of the "wobble" that works the fixing bolt free.
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Old 07-03-08, 11:38 AM
  #28  
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Happened to me earlier this year....sort of....I noticed my "pedal" was loose then looked down and saw the whole left crank was loose....I got home by stopping every few minutes and finger-tightening the crankarm bolt....then at home gorilla'd it tight....no problems since.

Doug
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Old 07-03-08, 12:40 PM
  #29  
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I think you'll find a little blue locktite on the bolt (where you have a bolt) will work better than the gorilla method. I have taken apart cranks that are ruined because of the gorilla method...the arm is mashed all of the way to the end of the taper on the spindle.
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Old 07-03-08, 02:12 PM
  #30  
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My cranks are sugino. I really have no idea about maintenance, I didn't know that I needed to even check my cranks after 300 miles. My LBS told me to bring my bike back in after a month to adjust it after I rode it, shouldn't they have tightened the cranks then? Regardless, I'll be checking every time I go out now.
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Old 07-03-08, 02:38 PM
  #31  
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Holy crap. I've never even heard of this happening to me or anyone else ever before. I've never tightened any of my cranks in at least 25k miles. I didn't even know it was a thing that could loosen.

Lucky me.
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