Well,the good news is changing the oil to Motul atv/utv 10w/40 mineral oil has worked wonders for the starter clutch issue. I’m not getting any slippage,so far I hasten to add!.
The reason I chose the above oil is it’s proper mineral oil,opie oils,the co that sold it assured me it’s fine if that’s what I wanted to use but couldn’t understand why I wouldn’t use a semi. He obviously doesn’t own a z air cooled!
And the oil was inexpensive,I’m losing oil past the gearchange seal and constantly topping up, I am experimenting with a possible fix on that........
I’m not happy with the choke situation though,I want to be able to pull the choke full on and press the starter and have it fire right up but the choke doesn’t seem to do a lot. I know the carbs are clean,I’ve had them apart so many times. I’m wondering if altering the pilot air screws from 2 to 2.5 or 3 turns out might help?
Edit: I’ve just tried going from 2 to 3 turns-no difference,so I went to 4-no difference,then I went back to 1.5 turns out and it wouldn’t start on full choke. Once started it will tick over best on half choke,at 1.5 turns out it cuts out if I pull out to full from half.