esmarj wrote:
> Hi Johnny
>
> I don't know what casued the indexed steering, but I have believe it
> comes from carrying my bike on the roof of my car, or by having it
> hanging from the ceiling in the basement !?
It's relatively common if you carry your bicycle on a fork mount car top
rack for long periods of time.
When a bicycle is clamped by the fork, into a fork mount, the fork and
headset are held rigidly in place. As the vehicle goes down the road the
headset will be constantly absorbing small shocks. This would not be a
problem if the headset were also turning, because the lubricant inside
would be distributed by the rolling of the bearings. But the headset is
not turning and therein lies the problem. It's called fretting.
Jobst explained this all many moons ago, but the link to it is gone, his
exact quote was "The damage occurs when these small motions occur when
there are no steering motions to replenish lubricant while the bearing
balls fret in place. Fretting breaks down the lubricant film on which
the balls normally roll and without which they weld to the races and
tear out tiny particles."
On a roof rack where the bicycle has both wheels in a tray, and the
bicycle is secured by the frame, headset bearing fretting shouldn't be a
problem; not only is the headset is able to have a little motion, but
there is less shock to the headset because it is cushioned by the tires.
Fork mount racks seem to be going out of style, but for a while they
were very popular. I had to jury-rig a Saris tandem mount to fit my
Thule bars, as Saris has the only tandem rack where the bike isn't fork
mounted.
It's unlikely that hanging the bike from the ceiling had any effect on
the headset.