Z1OwnersClub GB

It's been a long time that z900 has been used on the road ,maybe six years I will be riding it again this summer, have Been for test rides on it done about twenty miles on it this last weekend, there is a problem that was not there before the ignition can cut out while iam riding and I will come to a stop, its not the fuse , wiggle the key and the ignition will come back on again and i can continue anyone know what this could be

If, as you say, wiggling the key in the ignition switch restores normality then it suggests the contacts within the ignition switch itself are dirty.
Because the bike has been stood for so long it could well be that if you operate the ignition switch a good few times it might clean any corrosion off the contact faces. You could try spraying a little WD40 into the ignition switch itself, if that is possible, & see how it goes.

My thou started doing it about 3 weeks ago, i found some of the bullet connectors under the tank a bit wobbly and i could stop the bike running by wiggling them, so i fixed them and while i was at it i thought i would re-route some of the clock wiring and replace idiot light bulbs when i found the switched live on the back of the ignition switch was actually broken off and only touching the rest of its fixing, i re-soldered it back on, as well as stripping the switch cleaning and a touch of silicon grease, so it may be worthwhile to check the switch and clean it it's an easy job.

Paul, as said, sounds like a bad/loose/corroded connection.
Sure the fuse is a tight fit too.

spray some servisol super 10 down ign switch and turn on/off for a couple of mins

Pull bullet and block connectors clean off nasty green poop and squirt them prior to assembly

Check fuses-don't trust them looking OK-

I pushed a z1r three miles with knackered ignition ...Fuse wire broke inside glass cartridge.

Could happen to anyone! Why me

Good luck