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Discussion Starter · #1 ·
posting this here because it involves my 29er. se stout, all stock, the red one.... i think the 2009.
it seems every 5 to 10 miles or so i have to tighten the crank bolts. sometimes they get loose enough during a ride that i can actually see, hear and feel the crank wobbling.
other than locktite, what can i do to prevent this?
when i re-tighten them down i pretty much crank the hell out of them.
thanks.
 

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I'm going to guess that you have wallowed out the crank arm and it is pretty much toast. What you can try is to pull the crank arm off clean it and the BB spindle really well and then put locktite 820 on the interface and 242 on the threads. This might buy you some time if my assumptions about your problem are correct. But the only true way to fix it is to replace the crank arm.
 

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Discussion Starter · #6 ·
dont know what kind of spindle..... the one that came stock on the bike.
as far as replacing parts, at some point but not now.
when i tighten it up it seems to fix the problem until it loosens again during riding.
 

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The spindle is most likely steel, and the crankset aluminum so it doesn't take much riding with it loose to round the softer aluminum out, then you tighten it and it comes loose again and so on. When the retaining bolt hits the spindle for the crank to get tight, another words, the square hole on crankset is too big to get usefull tension/tightness onto the spindle, that's the fat lady singing.
Follow "customfab's" advice but i'll add...after you put it back together, go for a mile ride or so and retighten, Not loosen than retighten, just make sure it's still tight while loctite is still wet, then let dry overnight.
Also, "Sheldon Brown's" website has a good read on crankset install that may shed some light on this for you.
You can look up your bike's specs on "Bikepedia's" website to know the crank/spindle interface.
If it's not square taper just locktite the bolts and ride some, retighten and you should be good.
Make sure there's no glob of grease in the bolt hole that keeps the bolt from fully tightening and make sure to clean of threads in hole and on bolts before the locktite.
 

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Yep ^, if it's square taper that's most likely your only glimmer of hope to save it.
I've seen these problems with square taper, ISIS and Octalink interfaces. When you have a spindle made from steel and a crank from aluminum it doesn't take much for one to tear the other up.

Since you don't even know what kind of spindle it is just take it to a shop and have them fix it as best as you can afford.
 
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