Stibbs wrote: ↑Sat Oct 24, 2020 4:57 am I found a simple twist of the throttle whilst holding the back brake works. About once a month. No probs

This. Point the nose into a handy kerb and give it the beans. Works a treat on my old Hondas too.

Update on my clutch judder.
I took the burgy to my local bike shop (Alford Bros, Folkestone). The workshop manager took it out for a test run and basically said "They all do that a bit sir". He said he was very happy to strip it down and clean the clutch etc but said it would be un-likely to make much difference. So I brought it back home. However, I have a manual so decided to strip it down myself, this also gave me the opportunity to get busy with the ACF50 on the frame and clean up some scabby alloy. There was quite a lot of dust in the clutch and also the variator although I left these in place and finished of the clutch with a good spray of clutch cleaner.
I have only had the opportunity to test it up and down my driveway but it seems transformed, very smooth. So the mechanic in Alfords wasn't quite right on this occasion.