Loose headset in cold temperatures

andyeb

This morning I got my almost brand new Pinnacle Arkose 3 out of the shed for the club run and during the pre-ride M check I discovered the headset was slightly loose.

I had only recently set the headset tension after swapping the stem for a slightly longer one. However I did the adjustment at room temperature.

Having left my bike inside the conservatory for a while (warmer than outside, but not as warm as in the house), I've noticed the headset is almost tight again.

Is it possible that the headset just loosed because the aluminium head tube contracted more than the carbon steerer in near freezing conditions?

Has anyone else come across this? I guess I could set the headset tension while the bike is cold, but then I'm worried it might become tight when out on warmer rides.

My brother has a much older Arkose, which has had intermittent problems with the headset working loose since it was new.

Any thoughts or advice gratefully received.

cheers,

Andrew

meanredspider

I suppose it's possible - though I'd imagine that it's contributed to a problem that was already there rather than the only cause. Carbon fibre does have a low coefficient of expansion.
Many aluminium bikes have carbon forks - do they have aluminium steerers though?

frisbee

My GT has an aluminium frame and a carbon steerer, I've not noticed the headset tightness change. Although it did settle and loosen so it needed adjusting a few weeks after I first set it from new.

andyeb

meanredspider wrote:

I suppose it's possible - though I'd imagine that it's contributed to a problem that was already there rather than the only cause. Carbon fibre does have a low coefficient of expansion.
Many aluminium bikes have carbon forks - do they have aluminium steerers though?

I have two bikes with carbon forks - one has an aluminium steerer, the other (the Arkose) definitely has a carbon steerer - I noticed when I swapped the stem over.