teamferret

The A refers to the size of the piston. They are grouped into size bands and matched to a bore. you need to make sure you put an A back in or you will almost certainly end up with a loose or tight piston

The MZ301 piston is very similar and can be found at good value

I've only had a quick look, but I would say that it's the lining on the clutch that is giving you problems, Re-line perhaps???

All the engine bits are available from Villiers services. Don't think those forks are the right ones i think they had MP's

I've bought off ebay in the past, but agree there seems a lot less now. Try Gumtree and facebook market place

No, sorry to mislead - you can register the bike without fuss, but if you want to use it on the road it will have to be MOT'd and insured. As a way of getting a number it is very easy and then upgrading to road use after

No, the DVLA have introduced this scheme to reduce the amount of unregistered vehicles, you can even get a reg plate for a horse box. I've done a couple of my trials bikes so that they are included on my insurance

very tidy must have cost a bit to put together, but well worth it

If you don't mind having a Q plate you can register it like a farm vehicle and you won't need MOT or insurance

Any pictures?

Try the obvious things first. Strip each connecter clean and ensure each one is tight. Disconnect the kill switch. Check the earths including the stator to the engine. Make sure the flywheel woodruff key is present and correct (if the timing is too far out it won't spark. Substitution with known components from another bike follows if you are lucky enough to find one. Rex Caunt or electrex world may be able to help, depending if they think there is enough interest in doing a system for that bike. If all else fails modify a pit bike system to fit

smashing

Look on ebay, there is a guy who breaks just scorpas

Yet you can use a 4-speed bantam that came out in 1969

TY80 Still takes some beating