HI  all,

I have a YZF 750 R from 1993 and the oil light come on when I rev it at about 12000rpm and then stays on till I rev it again! 

I check and there is always enough oil. Is that the  sensor?

any help will be welcome

Regards

Andrea

If it's anything like the Thunderace, it probably burns a certain amount of oil as a general course...
It could be that you're not quite topping up as much as you think. Make sure you're topping up the oil on a level surface and that the bike is perfectly upright (ether on a pair of stands or by looking for the balancing point).
My Thunderaces light comes on when the oil is a little low at high revs, but goes off again once I drop the revs again and the oil pools a bit more. It may be that yours is doing the same thing but has something else on it that's holding the light for longer...
 

When was your last complete oil change? Even topping up regularly still ends up with week oil eventually.