Starting issue

[ghostbiker]

well this is an odd one.
Went out today and bike as allways started at first touch of the button (with choke)
came off choke affter 2 mins idle and took it for a blast.
bike behaved faultlessly other than the tyre letting go a number of times. but its just passed its wear markers and the grip just seems to have gone from good to 0 in about 50 miles lol
anyway, clocked up about 40 mile then stopped. waited 2 mins and started fine, rode a few miles. stoped and waited 5 mins.... bike wouldnt start.
turns over like a good un but just wont catch. there is a smell of fuel but not realy strong.
affter a few mins trying it fired up and the instant it fired up it ran perfectly again.
stopped a few miles down the road again, waited 5 mins and again it wouldnt start. took a few mins trying and then it caught and away i went.
Parked up at home left bike for an hour or so and went out. started first press.
im at a loss