I had my cam belt and rollers changed today and this is what the mechanic found. He reckoned it was a few days away from total topend destruction. How on earth did it still run and run OK with the timing that far out? It's the cog/pulley off the end of the crank, for those that don't know.

Well that was bloomin lucky

I just thought I'd add that this caused an intermittent rev counter problem as in that it would stop from time to time, which increasingly got worse, as in it would stop working more often and for longer. I expect it was because the timing became further and further out as the channel in the pulley wore. There must be a crank and cam sensor, else how would it know!? The taco has worked fine ever since this was fixed.