Z1OwnersClub GB

cam timing should look like this note the position of the cutaways in the end of the cams

Nick.s wrote:I just had a look at the carbs and there is a number on the engine side flange, it’s hard to see but the offside carb has 299 04 or 01 it’s hard to see. Does this help with id?

I have six sets of these hanging up and another couple in bits and every one has different numbers, even those from the same model and year .
They are factory markings and most likely denote, batch, month, year and possibly build spec etc.
I doesn't really make any difference as all the bodies are the same like for like and they are only jetted differently to suit whatever model they were used on because of the varying styles of exhausts and airbox fitted.
All you can tell without taking them off is that fuel mix screw means 26mm.
Whether they have been bored out or modified is another story.
These can be bored out to a max of 30mm as I did in my Café build thread.

Quick update, I took the rocket cover off, counted from above the arrow “29” teeth to the 28 mark
What a plonker . Hopefully that will do the trick, I can’t finish it until Friday, so will keep you informed.

Do they have a vacuum stub on number 3 carb, if so the chances are they are thou A2 carbs if not they are possibly B 2 carbs i have a set of each with the difference being the vacuum stub and pilot jets being much longer in the B carbs and accelerator pump models for the A3a thou.

There are vacuum stubs on all carbs. I’m pretty sure they’re z1000 1977 probably 26mm I expect I measured them wrong.

should only be 1 vacuum stubb on number 3 as the drilling goes into the carb throat, others are vents and drilling's go into carb bowls.

I can’t see a vacuum stub on number 3

They are not vacuum carbs so you don't have a vacuum tap do you ? (unless you are running the vac tube from one of the intake rubber balance ports)
The stubs on 2 and 4 are float bowl vents and should just have a short open ended tube to the atmosphere on them.

So to hazard a guess from the jetting you have in them, they are probably 78/79 26mm ltd carbs, look out for leaks around number 1 overflow once you get them back on and running..

Well I’ve just set the valve timing properly, and checked the ignition timing. It’s still the same, all ok to 3 k revs then it splutters and won’t go any higher unless I back off the throttle then I can ease it up a bit
What to check next? Could it be carb problems or electrical?

Hi Nick.

Whereabouts are you? I am in Tewkesbury.

Near Wotton-under-Edge, about 30 mins.
I’ve just taken the plugs out and they are really black sooty, looks like it’s running really rich. I’m trying a new set of coils just in case it’s that.

it does sound like a coil breaking down

New coils fitted, no joy

Does sound over rich.
Have you checked the carb mouths for Air corrector jets.
if they are fitted when using the airbox it will cause this.