[Flip]

The switches are not the best to be honest, I replaced mine when the bike was about four or five years old and the second one didn't last that long so I gave up as you can always tell when the gearbox is in neutral anyway and I'd rather trust my 'feel' than a potentially dodgy switch with I hit the starter while it's on the side stand (no in-gear cut out on the early bikes remember).

As Utopia says (on the early bikes at least) the switch was supplied with some shims to enable the switch to light at the correct time (I presume there must have been some tolerance issues with the engine cases?).