Swinging arm flex

Hopefully the swinging arm has no (or minimal) sideways movement otherwise you will get an MOT failure and intersting handling. However you will get a bit of movement due to the isolastics. Working from memory I would guess that the gap between the passenger footrest and the singing arm varies by maybe 1/4" when the rear wheel is given a bit of sideways force. I can check properly once sat in front of it if no-one comes up with anything better.

I'm no expert but I think Tony is about right, of couse there should be basically no play between the pivot and the gearbox cradle, if there is any play here you'll need an oversize swinging arm spindle (if they are still available ?) - About 20 years ago I had trouble with my first Commando (a MK3 Interstate) at my local MOT station who failed itbecause 'the swinging arm bushes are worn out mate' - The tester 'proved' this by moving the back wheel both ways laterally, stating that there should be no movement. Of course he was actuallymoving the entire engine/gearbox/swinging arm/wheel in the Isolastics. I pointed out that on the Commando the whole thing was rubber mounted and that he should just look for movement at the pivot instead, he took this on board, checked it and passed it so all was well in the end !