You won�t notice anything when holding the handlebars. Too much leverage. I had to remove the wheels and forks to be able to feel how bad it really was.

I had the same issues with my Tenere, with a worn TKC80, so I figured with a new tire, it should be ok.

Nope...

Had to order new bearings, and watch youtube for a while, buy a Dremel and some other hardware.
It took me about 5 or 6 hours to change them.
But, I figure, next time, I should be able to do it in about 2 hours...

I was wondering if it could really be the tyre.
I put the bike on the centre stand and tried to feel the notch through the bars, but as you said, very difficult to feel.
However when I lifted the wheel from the front spindle, ( the crash bungs ) it seems as if there is some wear present. It has a little bit of resistance, then kind of flops over to the side. A bit like its climbing a hill and then rolls suddenly from the top down the side ( if that makes sense )
Anyway, I've ordered a new kit from Wemoto ( the Japanese one )
Now I need the time to do it or I may ask a garage to sort it. I don't have a bearing puller.

I broke off the bearing housing with a screwdriver, and cut a deep notch in the remains with a dremel-tool, and split it with a chisel (it is very hard steel, so very brittle)

Then I used the remains upside down to help install the new bearing.

Search for it on youtube. Several videos there. Some use screwdrivers as a wedge to force the bearing off the stem. I found that this was not easy, and used the dremel-method instead.

Ha! I can imagine it was a headache to do either way.
I did it over 20 years ago on an XS400, my first bike.

I'm going to go the lazy route and let a mechanic do it for me. Two kids gives me precious little time for basic maintenance.

They think 2 hours to complete. A lot less time than it'll take me, although not nearly as satisfying.

Thanks for your help

So Mr.Jlovold, it seems you were spot on in your diagnosis.
My steering head bearings had covered 39000mikes and I'm not a wheelie monster by any stretch of the imagination. As you said it was very difficult to detect any wear or notchiness through the bars.

The difference in ride-ability is astonishing.

The mechanic said there was very little wear, but oh what a difference.
It feels so much more confidence inspiring in the corners, the vagueness has gone.
My chicken strips of 8-10mm are already less after one commute to work.

Apologies to Avon and your trailrider tyre. Nowt wrong with them.
I'll be expecting it to be even nicer once I complete the second tightening in a few hundred miles.

Happy days.