# Play in the crank arm



## jfd986 (Jul 17, 2011)

I tightened the crank arm onto the bottom bracket (what a day that was, getting into the bottom bracket, woof) and my $10 socket wrench (NOT a torque wrench) made this clicking sound, so I figured hey, my bike's 30 years old...it's tight enough. Now I just noticed a bit of side to side play in the crank arm. Is it supposed to be tighter? If I get a torque wrench then will that make it tighter? I don't know why this ratcheting sound comes if the thing is not absolutely immobilized-tight.


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## cxwrench (Nov 9, 2004)

again...how can we answer your question w/o actually seeing your bike? if there is play, then no...it's not tight enough. the most likely reason your $10 wrench is making noise is that...well...it's a $10 wrench. either your bottom bracket is loose in the frame, or your crank arm(s) is loose on the bb spindle. you should be able to figure that out pretty easily.


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## PJ352 (Dec 5, 2007)

jfd986 said:


> I tightened the crank arm onto the bottom bracket (what a day that was, getting into the bottom bracket, woof) and my $10 socket wrench (NOT a torque wrench) made this clicking sound, so I figured hey, my bike's 30 years old...it's tight enough. Now I just noticed a bit of side to side play in the crank arm. Is it supposed to be tighter? If I get a torque wrench then will that make it tighter? I don't know why this ratcheting sound comes if the thing is not absolutely immobilized-tight.


Lots of possibilities....

Assuming your wrench isn't broken, the ratcheting sound may be a stripped thread, in which case you won't be able to sufficiently tighten the bolt. But before digging further into your crankset/ BB, I suggest verifying that the wrench itself isn't the problem, or that you're simply using the wrong (hex?) socket and it's slipping on the bolt head.

That said, as cxwrench mentioned, another possibility is that the crank arm/ BB spindle interface is worn. Seeing as the spindle is steel/ chromoly and the crank arm is aluminum, I'd go with a worn crank arm. Also, if it's on the drive side it might explain the 'bent' chain rings, because as that spindle spins (and the crank arm rocks side to side), you'll see the chainrings sway with it. 

If it were my bike, I'd back the crank arm bolt out, remove the arm and examine the parts. If the bolt has worn/ damaged threads, you'll know the cause. If not, try to re-thread the bolt into the spindle and see if it catches at any point. Clean and grease the bolt before doing so. What you find will determine the options you'll have, so update this thread and we can assist further. 

BTW, when accurately calibrated, torque wrenches only tighten bolts to the given value and display a reading of torque applied. You could easily apply more torque with a ratchet just by applying more force.


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