Author Topic: Aluminium Steerer Flex  (Read 794 times)

Aluminium Steerer Flex
« on: 03 April, 2021, 09:54:06 am »
I have just built up a steel frame with new carbon fork and headset. Problem with Steerer Flex. If I setup the bearings to be 'just not loose' as soon as I sit on the bike the steering binds. Once loosened off to allow normal riding it stiffens up when braking. Rather disconcerting. I'm wondering what my options are?
1. Mess about with a different headset with more compliance.
2. Fit a nice custom steel fork (tried a cheap one, no problems) or carbon with steel steerer (do these exist?)
3. Take it all back to Spa and complain (anticipate 'well no one else has...)
Just for info it is a big frame, 200 mm between bearings, rider weight of 75kg

LittleWheelsandBig

  • Whimsy Rider
Re: Aluminium Steerer Flex
« Reply #1 on: 03 April, 2021, 10:03:47 am »
What sort of headset? Aside from the braking behaviour, there shouldn’t be enough elastic movement to change bearing resistance when you sit on the bike (ignoring tyre to road). Without seeing anything, my first guess is a flipped bearing seal or suchlike.
Wheel meet again, don't know where, don't know when...

Re: Aluminium Steerer Flex
« Reply #2 on: 03 April, 2021, 10:47:43 am »
Seems a bit odd. As per LWaB might be worth checking seals and stuff. Presume it’s a 1 1/8 steerer and have never had a flex problem with alloy - at 175mm headtube length and similar weight. Could there be a parallel issue with the cups?

Re: Aluminium Steerer Flex
« Reply #3 on: 03 April, 2021, 04:05:48 pm »
As you suggested it's a 1-1/8 cartridge headset. I will take it apart again and have a check. I don't think it's misaligned as it's smooth over the range of bar movement with no load on.

Re: Aluminium Steerer Flex
« Reply #4 on: 03 April, 2021, 06:43:02 pm »
Found the problem, a shim binding. There was some bodging to fit it and I had not taken account of the tight clearances.

Re: Aluminium Steerer Flex
« Reply #5 on: 03 April, 2021, 11:40:21 pm »
Good stuff.