Busted Head Bearings?

[Torn-Thorax]

Ever since I dumped my curvy in ditch a few months back, i've been experiencing that "flat rear tire" feeling while cornering (no, my tire isnt flat). Also, ive tightened my lower stem nut as tight as it goes, and while it doesnt have play, it still to too loose when driving. My question is, what do i need to replace? just the upper and lower bearings, or also the races? If it take the stem off (again) what should i look for in terms of wear? Thanks again.

[Sid Squid]

By lower stem nut, do you mean the notched adjuster ring under the top yoke? If so it's not supposed to be tight, only to be turned down just enough to remove play and no more.
A symptom of overtight bearings is the steering rolling from side to side at low speeds.
The bad news: If they weren't damaged before, running them tight for any period will mean they soon will be.
If necessary the bearings will need to be replaced in they're entirity; bearing, race in the frame and race on the steering stem too, they are supplied as a set.

[Torn-Thorax]

Bad news indeed. I am refering to the "notched" nut. I had a feeling that i may have overtightened them initially. The problem was that if they were only tight enought to remove play, then the bars could just bounce around lock to lock. Maybe I took it too far. What exactly do damages races and bearings look like? Can you even tell with the naked eye?

[jambo]

Looking at them by eye isn't the best way to go.

Get the front end off the deck, you should be able to turn the bars from lock to lock in one smooth action without feeling it stick anywhere (Usually it'll stick at dead centre if at all)

The less resistance there is to movement the better, there are plenty of things that are going to stop the front end flapping about when it's got about 100Kg sat on top of it.

With the front wheel off the deck you should be able to pull and push the fork bottoms back and forth and not feel any play in them. When you tighten up the stearing head hut it will take a little play out of the system too.


HTH

Jambo

[Torn-Thorax]

The bearings are perfectly smooth. Steering just seems too easy to move. At very low speeds its hard to keep her in a strait line. (less than 5mph) It's not a big deal to me, as long as it won't contribute to head shake and tank slappers. I hear that is terrifying.

Also, for the record, at less than 10 stone, I'm a feather weight .

[Lozzo]

Looking at them by eye isn't the best way to go.

Get the front end off the deck, you should be able to turn the bars from lock to lock in one smooth action without feeling it stick anywhere (Usually it'll stick at dead centre if at all)


Not quite correct.

You need the front wheel ON the deck but able to turn lock to lock freely and without too much pressure being put on it. Notched steering head bearings don't show themselves until they are way too far gone when you take the weight off the front. Think about how the steering head is built and it all makes sense - it's the upper race in the bottom of the headstock that is usually the worst affected, take the weight off the front and the pressure is off the worn bearing so it'll move freely and not show the notchiness.

This is why MOT stations have a revolving plate set into the ground, it's so they can check for notchiness because it doesn't show when they have the front in the air. Trust me on this, it's basic motorcycle mechanics and I'm doing the MOT testers course at the moment.