The first thing I did was check the genuine Yamaha parts, and yes, I damn near had a heart attack! I'll have a look around for the pump you mention, at �30-�35 I may as well replace it to be safe, rather than have my pump pack up on me while riding.

I wondered if it might be something to do with air because I remember on my old bandit, (carbs and no fuel pump) if it was left in the sun (it was black as well!) it sometimes wouldn't start - if I sat quietly I could hear air hissing out of the filler cap! So I'd just pop the filler cap, pressure would release and the bike would start right up. I'm not entirely sure why pressure prevented it starting, may have just been a coincidence.

Anyway, thanks Pleiades!