Hi Steve, be very wary riding with dodgy float shut offs – I had a similar problem with my RB some years back after having it laid up for a few months – and after one ‘spirited’ ride out on dry roads I had a monumental rear end slide that very nearly had me off. The only thing I could trace the slide back to was petrol on the rear tyre….
So be careful and make the time to clean out the float bowls PDQ Steve.. 
Cheers.. Glenn