I'm a tad embarrassed to ask this question. My M20 came to me with the wheels off. They are definitely the right wheels, all matt green. I've fitted them in the frame and checked the nuts, bearings and spacers are all there. BUT I can see the front wheel is not central to the forks. The same is true for the rear, although perusing the various diagrams here and elsewhere tells me (I think) that the rear rim does not run central to the frame.
Is this right?
When I finish the gearbox overhaul I will place it back in the frame and check the chain run to the rear sprocket. For now, though, I'm puzzled.
Allan, neither wheels on an M20 will be in the centre of the forks. But regardless, the centre of the rims should be in line with the centre of the frame. Ron