Z1OwnersClub GB

The engine runs at 4,000 rpm when cold start is on full and by gently moving the lever down, it will run at 2,000 rpm. Move the little a bit lower down and engine stalls.

Last night I took the carbs off and cleaned the cold start plunger thingies and this has made no difference. Also cleaned the idle needle (set at 1 1/2 turns out) and main jets - didn't take the top off so main needles are untouched but did give them a wipe, not that they needed it.

It runs the same way but once it stalls, engine will not start again, unless I qive it a squirt of easy start - could just be the plugs are getting fouled from running rich.

Anyway, the question is is there anything I can do to get the engine to run at 2,000 or lower rpm until it warms up? Is something out of adustment or worn, if so, what and how etc

(I am running engine without the airbox connected so that may make a little bit off difference but last time I played, running without the airbox was better).

Note: I have not checked the timing but don't think that ist he problem asthe engine would either run or not, and not stall like this but ........?????

It sounds as if it’s running week at tick over. Are the pilot air passages free? Take the pilot jet out, put you finger over the hole and blow down the outer air passage. You should hear air coming out in the carb bore. The inner air passage in the carb mouth go’s to the needle jet and has little effect at low speed. Check the pilot jets are not blocked and the air screw is about 1.5 turns out.

Try using a Gunson Colortune tou can see inside the combustion chamber saves a lot of guesswork.....

popsA1 wrote:It sounds as if it’s running week at tick over. .

I can't get it to tickover - once I move the enrichement lever so revs go below 2,000 rpm is stalls.

I have to admit I did not clean nor check the holes/drillings in the carb bodies but all the jets - the bits that can be unscrewed - are spotless and clear.

Looks like I'll need to take them apart once more; getting quite lot of practise doing this, although the hardest bit is removing/refitting the push/pull throttle cable.