Bicycle Mechanics - how tight for the cassette installs?

ok, last night i installed my ultegra 12-25 cassette onto my velocity aerohead. then i went and tighten the cassette lockring. how tight should it be? should there be a loud crack when it's tight?

oh, and do you need to use the chain whip to tighten it down with?

You should never hear a loud crack from anything you tighten. I believe the torque spec for cassette lockrings is 30Nm. You don't need a chain whip to do anything to a cassette. Just the cassette remover. I would take it apart and figure out which piece has now got a crack in it.

ok, last night i installed my ultegra 12-25 cassette onto my velocity aerohead. then i went and tighten the cassette lockring. how tight should it be? should there be a loud crack when it's tight?

oh, and do you need to use the chain whip to tighten it down with?


:eek: uh, yeah should definitely check for whatever broke.

The chain whip is for removing them.

ok, last night i installed my ultegra 12-25 cassette onto my velocity aerohead. then i went and tighten the cassette lockring. how tight should it be? should there be a loud crack when it's tight?

oh, and do you need to use the chain whip to tighten it down with?

Was the loud crack a single crack or was it a series of cracks like a ratchet? If it was a single loud crack, you are probably in trouble. You broke something. But if it was a series of "cracks" or pops like a ratchet, the lock ring sets down onto small "teeth" on the face of the 12 tooth cog. It will make a buzz kind of noise. That should be normal.

Just get it snug. You shouldn't have to use a cheater on the wrench to get it tight enough :eek: :D

ah.. i'll use the torque wrench tonight to set it at 30Nm. i wasn't sure how tight it should be.. so i just stopped while i was ahead, so didn't hear a loud crack yet.

ok, last night i installed my ultegra 12-25 cassette onto my velocity aerohead. then i went and tighten the cassette lockring. how tight should it be? should there be a loud crack when it's tight?

oh, and do you need to use the chain whip to tighten it down with?
The ratchet teeth on the lockring does make a significant noise when you finish tightening it. Don't go crazy on it, the ratchet holds it, it's under very limited lateral stress anyway, so it will hold up ok if you get to the ratchet crack-crack part of tightening it.

You don't need a chain whip to do anything to a cassette.
I'd love to see you take a cassette off without one or a hyper-handle

I'd love to see you take a cassette off without one or a hyper-handleA rag will work.

I believe the torque spec for cassette lockrings is 30Nm.

For Campa it is 50 Nm - stamped right on the lockring. If yours is designed for 50, and you use 30, you may end up with a problem.

A rag will work.

I use a leather gardening glove.

For Campa it is 50 Nm - stamped right on the lockring. If yours is designed for 50, and you use 30, you may end up with a problem.

But I have a Campy Record cassette on a DT Swiss 240s hub. The Campy lockring says 50nm and the DT Swiss lockring says 30nm. What do you do? Go 30nm or split the difference and go 40, or leave the torque wrench in its box? I also have a Shimano lockring that says 40nm.

Al

Interesting question. :)

The cassette manufacturer assumes that torque to properly compress the stack to achieve proper spacing, regardless of the hub manufacturer.

The hub manufacturer may be speccing that torque so as not to blow up the hub.

So for Campa or Shima, the proper torque to achieve proper shifting is their own spec. The hub???

I would put that question to the hub manufacturer.