Hi Graham,
Terrot built tens of thousands of bikes, so let's assume the little bike worked fine when it was new, and worked OK until it stopped working. Most likely it wore out. Probably at the end the owner got sick of it not starting on the kick-starter and having to push it down the hill and jump on when it fired.
The idea of restoration is to measure and check everything, replace what needs replacing and fix what needs fixing, then enjoy the bike as it was when it was new. If you want the bike to run, you'll have to do these things - sadly no amount of forum chat will make it run if the thing is worn out. If the man at the engine shop tells you the bore is worn out, it's probably worn out. New rings won't help, because they are round, and the wear in two-stroke bore is not. How's the big end? The little end? Does it have any compression? If the engine is worn out, it will be very hard to start.
I'd be more than happy to have a look at it for you, but I suspect I'm on the other side of the planet. Perhaps you can hook up with someone experienced who lives locally? In the meantime, if you want it to run take the advice above and spin it over with a drill (or whatever), or just push it down a big hill. It will run, with the rattle and clank of a worn-out two stroke.
Cheers
Leon
