Triumph Tt600 Cutting Out At High Revs

HI i have a tt600 which runs fine around town and country roads but when on a bypass or fast road when you accelerate higher up rev range around 8000 9000 revs it splutters and cuts out. When you try to restart fuel pump wont prime after about 30 mins fuel pump primes and bike starts. Any help would be appreciated.
Thanks

 

You need to check fuel pump out put, possibly replace filter ad as something is restricting fuel flow/out put.

Cheers capt

 

OK thanks got fuel filter today so will try that first.

 

Fuel tank breather blocked perhaps?
If opening filler cap doesn't fix it - then I'm wrong.