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Old 04-27-24, 12:33 AM
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merziac
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Originally Posted by mpetry912
I would suggest to you that 300 inch / lb is too much torque for Campy cranks. I believe you are at risk of splitting the arms at that torque level.

Campy arms are quite soft and just blindly following "the torque spec" may not be the way to go. That said, I'd suggest no more than 240-260 in lb.for the "classic" NR / SR arms. Newer ones a bit more.

for Shimano square taper cranks, 280 - 300 in lb is fine.

An important mechanical skill is to develop a feel for when the "running torque" rises to a stall level, not just relying on when the torque wrench clicks. This "feel" is important when threading spark plugs into Porsche cylinder heads for example. Strip out a spark plug hole and it's engine out and the heads come off.

/markp
Yep, ya still gotta hold your mouth just right.

I was waiting for this, click stop torque wrenches can be dangerous in the wrong hands, Snap-On dictates activating the wrench at 50% of the target setting 3 X before the actual torquing.

Matco calls for making certain for the fastener to be moving when the wrench clicks its preset.

It is also critical as these and and more apply to all including making sure the fastener, nut, bolt and receiving threads are clean, free of burrs and lubed if called for.

And yes, whether its KZ 1000, Porsche spark plug threads or Campy crank arms, alloy or aluminum absolutely calls for even more extra diligence, experience and common sense with a steady, even hand.

Last edited by merziac; 04-27-24 at 12:37 AM.
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