Z1OwnersClub GB

I have recently bought a restored Z900A4. Very pleased, but it weaves left/right at low speed. Wheels seems fine/straight. Tyres are Avon Roadriders (new) and 42/36. Does anybody have a suggestion?

Give the bike a good going over and check that the steering bearings are correctly adjusted and that the swingarm and wheel spindles etc are not loose.
Don't trust that whoever restored it put it together correctly and also components bolted to freshly painted or powder coated surfaces can settle and work loose after a few miles running.

As above, and try a little adjustment of the Tyre pressures, factory pressures may not always suit modern rubber on a 50 year old bike.

Also check that front tyre beads have seated correctly.
There is usually a line moulded into the lower sidewall which you can use to judge that the tyre beads are concentric to the wheel rim.

Tyre pressures way to high, try 28/32

i assume you've checked headstock and wheel bearings..........

i'd agree pressures are a little high - i normally run 32 front/36 rear.

Thank you, every one, for your suggestions. I am taking up all of them today and hope to cure the problem.