A.J

tha arms on my 3 piece seem to always loosen themselves up. i've tightened tha arms down all the way but they still seem to come loose. probably a simple answer but frustration doesn't help ya think.

lotek 

A.J.
welcome to forums.
I have no clue as to what you are talking about, or
if your asking a question.
3 piece what? Campy large flange hubs?
could you be a bit more specific?
you might actually get an answer that way

Marty

A.J

sorry about that lol. tha arms of my 3 piece crank. they loosen up an i have to stop to tighten them while im ridein. i'm tryin to see if anybody could maybe help me out with why it could be happenin.

MichaelW

Do you have a bottom bracket with splines or tapered flats?
Do you grease the connection ?
Do you apply enough torque with a long allen key/wrench

A.J

to be honest about the bracket im not sure. the crankset is a cyclone precision one i put on for now untill the new crank gets here. i just started doin repairs an upgradein parts myself so im still in the learnin process of it. i didn't think about grease but we've did the allen wrench.

a2psyklnut

Blue Loctite!

Also, if you've got aluminum 3 piece crank arms and a 4 sided bottom bracket spindle, your cranks may simply be worn out.

Each time you remove and reinstall alum. cranks on a 4 sided spindle, the cranks must press further onto the tapered spindle. Over time, you'll get to the point where you can't press it on any further, or the aluminum is widened out to where you'll never get them tight again! Sorry!

BTW, according to Shimano, for their cranks on a 4 sided spindle you need 305-435 in lbs of torque! We usually set the torque wrench to 325 and tighten.

L8R