Headset play

[astrocan]

I have replaced the headset bearings on an 11year Trek 2000.
I cannot find the balance between a slack stem and stiff steering.
The bottom set came out really easily and, after cleaning up the seat in the bottom of the head tube the new set have pushed in really easily too. No need for a press to install or a rocket to remove.
I suspect that the seat has become enlarged, possibly through corrosion, possibly through inexpert previous installation.
I can resolve this by applying sufficient pressure through the cap nut to pull the bearing into the seat, but that is great enough to make the steering unacceptably stiff and will cause premature bearing wear. Ease the pressure and immediately the steering is lighter but the slack returns and I cannot find an ideal adjustment.
Has anyone tried using a bearing lock compound in this situation or experience of similar situations.
Alternatively is an oversize bearing an option? If so where from?
Thanks for your time

 

[Yellow Saddle]

Good news is that this can be rectified. You need some shim stock of the right thickness. This is sheets of thin brass in various (thin) diameters that can be cut with a pair of office scissors and wrapped around the cup before pressing it in. The measurement and insertion requires some skill, so take it to a machine shop or capable (motor) mechanic. The edges of the head tube need to be chamfered carefully to help the shim not catch upon insertion. I doubt the average bike shop spanner swinger can do it properly. The first trick is to map the head tube in terms of dimensions. You want to have a good idea in which directions the out of-roundness is and not just insert a wad of brass in there.
You will have lots of suggestions now to just cut up a beer can and use that, but without measuring you don't know what you're doing. For this you need a micrometer and some micrometer accessories. Do it properly.
I would also suggest you have a new headset fitted at the same time, perhaps one with replaceable cartridge bearings so that the new one will never have to come out again.

 

[lpretro1]

LBS should have a box of headset shims lying about...

 

[Yellow Saddle]

LBS should have a box of headset shims lying about...

He's after head tube shims, not headset shims. Don't confuse the OP.

 

[astrocan]

The head tube shims seem like they might work.
I failed to mention that this is an integrated headset that already uses cartridge bearings.
Would that make a difference?

 

[Svendo]

On my now dead Storck frame the original Acros bearings had a marginally larger diameter than the replacements I got (I tried several types).This is despite them being the same specification. I solved the play-without-overtightening problem with a couple of wraps of parcel tape, carefully cut to size. Inelegant and required occasional replacement but worked. It's looking like I have a similar though less severe case with my new Cannondale frame, I've just today tightened it as much as I'm comfortable doing and we'll see how that works braking down steep slopes next time I go out on it, and if the steering is too tight. I'm less concerned about bearing wear as they're easily and cheaply replaced.