Thanks for your reply.
I can't find the exact manual for this model, its a 1979 Puch Maxi 2-speed automatic, but any standard Maxi manual mentions the decompressor.
I have the standard black starting lever with one cable, this goes down to a plastic Y device which branches into two cables, one to the decompressor and a short one to the top of the gearbox. When the starting lever is pulled the Y piece operates both cables simulataneously although they can be adjusted independently.
The manual actually states that the starting lever operates a decompressor and that it should come into action before the starting device (clutch?).
Since I have spark and petrol then I gues its either compression or timing. The mileage is only 4679 so I wouldn't expect massive wear but operating the decompressor would of course mean low compression. I'm reluctant o alter the timimg yet since it belonged to one old lady and I'd probably make it worse.
No apparent run/kill switch, I guess its left down to the decompressor.
Just one large black switch moilding. It has three switches one large one with two positive positions plus a push position, one red button which operates the horn and then a small pointed switch on the inderside of the moulding which has two positive positions plus it can be pushed in. Again I can't find a picture of a Maxi with a similar switch but everything seems original and untouched.
It seems to be quite a common problem with the Maxi and one guy is selling his on ebay cos he just can't cure it, there have also been post in the forum with the same problem.
Hopefully all will be revealed in the fullness of time.