| Hi dodgydan
Check the posts under 851 / 888 and you'll find that my own SP4 did the very same thing just a few months ago. I rode the bike home without noticing there was even a problem, but as I pulled up on the drive and the revs dropped, on came the light. Same symptoms as yours - would go out above 2,000rpm.
I fitted an Electrex regulator, and the problem's cured. Cost me about £70 in total. It's easy to fit - it's a straight swap and plug in.
Steve |