Correct fitting of 105 BB & Chainset

milese

I've got a Carbon Spesh Tarmac, came with a 105 bottom bracket.

The other day I took it off, along with the BB cups.

I put it back on and it creaked, so I've looked at the Shimano website, and bar not being able to use the torque settings, I tihnk I've fitted it correctly.

The cups have just screwed in, and been done up pretty tight (cant use torque wrench on a spanner!) How tight should these actually be, as I've done them up as tight as I reasonably can.

I then greased them and the crank shaft, slid them in and popped the other arm onto the greased spline, the minimal torque setting for the plastic cap is far too low for my wrench, so there is a possibility that I've done this up too tight?

I then greased the pinch bolts and the spacer, made sure the spacer was in the right way, and torqued up the pinch bolts to Shimano spec.

And it still creaks under load, making a loud hollow carbony noise.

Any ideas?

nicklouse

sounds like maybe you need a bit more force on the cups.

you have not said why you removed the cranks and cups in the first place?

milese

I was going to fit a compact chainset, but decided to man up instead.

The bike has done probably less than a thousand miles, 98% of which have been dry.

So the cups need to be done up really really tight?

markos1963

I have a 105 chainset and it suffered in the same way with creaking.
I cured it by stripping and cleaning the shaft and splines properly with a spray i got from work. I used lithium grease on the shaft but left the splines dry and reassembled. The BB cups are done tight but not over tight but the pinch bolts have been copperslipped and then done up very tight. No creaking in about a thousand miles and that involves crit racing and TTing.
The reason for no grease on splines is I think that when you tighten the nuts you are trying to compress a liquid and therefore not tightening enough, when the grease dries or melts then the crank is left slightly loose. Anyway that was my theory and it seems to have worked.

topdude

You don't mention greasing the threads on the BB bearing cups, if not smear a little grease on the cup threads and the threads inside the frame. They need to be as tight as you can get them with the correct tool.
It sounds like you have done everything right as far as fitting the chainset goes.
Also make sure it is not the pedals / cleats or seatpost creaking:D