In the interest of documenting everything, I had a little fiddle with the thing this evening. The clutch needs adjusting, it's still in the original position, and clearly has some slack, which might be affecting the starting, perhaps. 5 minute job, just didn't fancy it with cold fingers.
The motor is a K157fmi, so there are quite a few parts for it available from ali and other places like ebay.
Need to get a compression tester, been looking for one anyway for other stuff I have, so will grab something bike friendly shortly. I suspect it may end up losing compression, if not already based on what has been said so far about the strength of the engine! Found some piston/cylinder kits for under £60 so not too shabby if it is needed soon.
Now, I had the battery on charge for a few hours, and it was reporting as full, so I think that's probably ok. Will check the voltage tomorrow and see what its making then. It turns over very well, but wont start on it's own. So I will check the spark, fuel and air asap. Turned over consistently for a few mins (not more than 3-4 seconds each time, as I heard the starters don't like being run too long in one go. So, perhaps compression might be an issue...
Something is squeaking when I move it about, so I guess the brakes are rubbing or wheel bearings are dry? Will investigate further when it is NOT FREEZING outside.
Got a cover coming tomorrow.
Will try and bump it also, see how it actually rides if I get a chance before the weekend.