Suzuki GT185-correct gearbox oil ? Clutch still notchy.

[joeloss1]

I posted before and thanks for help so far. Just a query re: engine oil and how it effects gear change.

It had been over-filled (1.2 litres) with 20/50 mineral. I drained this and filled correct amount (0.8 litre) of 15/40 semi synthetic.
It is noticably better but neutral can still be tricky to find most of the time.....other gear changes fine and rides good.
I've adjusted clutch cable both ends....I think now correct adjustment....about 3mm play at lever.
Just wondering if oil type/rating needs to be any more specific on a '73 bike ?
Thanks.
John (UK).

[karl pa]

Neutral isn't that easy to get with these bikes when they are stopped and running,I normally need to shift into neutral while still moving or shut off engine.