ZZR 1100 1990 front end shake at 80 kms

Howdy crew, I have a front end shake (tank slap) at 80km's. I have no sign of the shake until right on 80kms then it goes away by about 85km, then it is only just noticable from then on but 80kms is right on it. The shake is only when I remove both hands, it doesn't seem to do it when I have one or both hands on the job. I'm thinking 1) get tyre rebalanced 2) front wheel bearings 3) head stem bearings?? not sure if there is one of these to hit first for this model or it might be something completely different. There is no damage to the rim that I can see. Trye wear seems fairly normal. She has done 70,000kms 1990 C1. I don't know too much of her history as she is second hand. I can't say that I noticed the shake when I first bought her but it wasn't until recently that I actually removed both hands and I nearly shit myself with the shake. I thought it was gunna do a full tank slap on me!! Cheers Pinebox

Got a pic of your tyre?

Bar ends in place?

I'd start with the tyre. I doubt whether a wheel balance would do much at 80km/hr. Throw a set of M5s or similar on and see what they do. As you've mentioned though check your steering head bearings and adjustment too.

If you have Battleaxes fitted the front commonly wears unevenly causing your symptoms. They need the pressure watched like a hawk. Run your hand over the sides of the front. You'll soon feel the heel toe wear.

Problem solved, the trye was the issue, you guys were right with the slight heel toe wear. The guys at the shop think that the tyre may have been off a different bike and fitted to sell the bike. The head stem did need a little tweek as well so those two together made for an interesting shake right on 80kms. thanks again from the bottom of my shake!!

Good result. Notice that the blokes with the answers were the extremely talented and intelligent ZRX owners

Good result. Notice that the blokes with the answers were the extremely talented and intelligent ZRX owners

Not really, just means there are old and have read about it or had it happened to them before.

Good result. Notice that the blokes with the answers were the extremely talented and intelligent ZRX owners

Not really, just means there are old and have read about it or had it happened to them before.

That's true but don't tell anyone OK