Inlet manifold worked loose, gasket fail

So I've been using the scoot happily for a long time now with little bother, typically once a week getting to work in Bristol. It must be over two years of reliable starting and riding in all weathers - hot, cold, wet and dry. The only thing I've been having to stay on top of is a very slow loss of air from the rear wheel and regular disintegration of my air hose regardless of whether I buy Indian or Italian. Regular oil checks have revealed no noticeable oil loss through leak or burn. MOT's have gone without a hitch.

All good then, until a few weeks ago when midway through my journey home from work it started running rough - not idling without throttle, and low on power. A test ride the next day revealed that the engine would race frighteningly fast with choke on, and die without it. This is symptomatic of air getting into the cylinder not via the carb.

Then it went cold. Then it snowed:

Finally today the snow has gone and basking in 8 degrees warmth I was able to take a look at what's going on. The inlet manifold has become loose and part of the gasket disintegrated, allowing air ingress. With the choke on this had the effect of a wide open throttle.

So now I need to drop the engine by a few cm's (again) to get the manifold off, replace the gasket, and fit it back with some nylock nuts and wavy washers. Tight. And hopefully this time it'll stay on!