Hollowtech ll BB question

G1032

I replaced the bottom bracket on my bike early last September. Previous one did about 8,000km. The one fitted in September has done just over 3,000km
Fitted a Shimano Hollowtech Ultegra BB.
Last couple of spins I’ve heard a creaking sound coming from what I think is the BB.
(I’ve removed and greased pedal threads to rule out the pedals as the cause of the creak)
I’ll remove crank and check BB tonight to see if there is anything obviously wrong with it but surely it should be lasting longer than 3,000km? (assuming its worn)
Most of the winter riding just gone was done in terrible conditions and I know asking how long a BB should last is like asking how long is a piece of string.

So the main thing I’d like to find out is how much to tighten the BB when installing? Maybe I’ve tightened it too much, maybe not enough.
How do you guys know when the BB is tightened correctly?

How long do you typically get out of the BB (especially when used over your typical Irish winter)

07Lapierre

I have one.... It's 8 years old this year.

Correction! Bike was bought in 2006, so it's 10 years old.

omri

If you have clicking noise tighten the bb some more and see if you still have it. I used to have same issue, there are many other suspects, as always it could be anything, but tightening the bb did the job for me. Check the manual whats the recommended torque.

NeedMoreGears

Have a look at the chainring bolts.

I had a creak develop over the past month or so that I assumed was the BB (Its around three years old and has around 20,000 plus on it). When I was adjusting the front mech the other day, I noticed some axial movement on the big ring. Three of the five bolts were loose - one very loose. After they were tightened up, all was quiet.

check_six

G1032 wrote: »

Last couple of spins I’ve heard a creaking sound coming from what I think is the BB.

A creaking sound coming from the bottom bracket?

I think we need to dump the 'bicycle' moniker for these vehicles and switch to the far more descriptive 'ventrilopede'.

All bicycles are able to throw the sound from any part of itself through the bottom bracket in a form of mechanical ventriloquism. Normally not from there at all. The wheel dropouts are always my number one suspect, and have proved to be a serial guilty party on my bike at least.

saccades

HT2 are pretty susceptible to over-tightening, kills the BB way faster.

3000 km through winter sounds ok for a BB, more than I get for mtb but a little less than my commuter, it's a disposable item.

G1032

saccades wrote: »

HT2 are pretty susceptible to over-tightening, kills the BB way faster.

3000 km through winter sounds ok for a BB, more than I get for mtb but a little less than my commuter, it's a disposable item.

Ya. I bet it's over tightened. It's not expensive but as said above the creak could be coming from anywhere

omri

Out of interest - how can you overtighten the ht2 bb if bearings are resting in two separate cups that dont apply any pressure on the bearings?

07Lapierre

omri wrote: »

Out of interest - how can you overtighten the ht2 bb if bearings are resting in two separate cups that dont apply any pressure on the bearings?

Its pretty hard to overtighten as the "tension nut" is plastic!

omri

07Lapierre wrote: »

Its pretty hard to overtighten as the "tension nut" is plastic!

So you mean overtightening the cranks themselves.

07Lapierre

omri wrote: »

So you mean overtightening the cranks themselves.

Possibly. I tend to tighten them be "feel". I don't use a torque wrench. If the feel tight, that's ok with me. I don't swing out of the Allen key.

I'd say a loose crank would cause a creaking noise, not one that was overtightened.

omri

07Lapierre wrote: »

Possibly. I tend to tighten them be "feel". I don't use a torque wrench. If the feel tight, that's ok with me. I don't swing out of the Allen key.

I'd say a loose crank would cause a creaking noise, not one that was overtightened.

The plastic cap is only by feel. Seen video someone doing it making it tight and then just backing up a bit. The arm bolts best with torque wrench.

When I had clicking I tightened the bottom bracket cups and clicking went away.

07Lapierre

omri wrote: »

The plastic cap is only by feel. Seen video someone doing it making it tight and then just backing up a bit. The arm bolts best with torque wrench.

When I had clicking I tightened the bottom bracket cups and clicking went away.

Yep, loose cups are a possible cause alright.

G1032

I think I've found the source of the creak. Looks like it was coming from the saddle.
I have had the cranks and BB off twice. Pedals off and greased. No luck finding the creak.

Until yesterday evening. I was out with a fellow boardsie. Bike started creaking and he immediately said it was coming from the saddle!! All I had to hand at home was a can of WD40 so sprayed some in the saddle rails and a small bit on the seat post. No creak when I took it up the drive for a test this morning.