Motorcycle Questions? Ask a Mechanic.
I'd say that the issue is with fuel being picked up, and being delivered out of the tank to the carb
as it only suffers on an incline then I'd say its possible the pipe exit is either being blocked by something or its moving around
I'd also check that the filler cap valve isn't sticking and so creating a vacuum inside the tank
if you loosen the cap when the issue occurs and it helps then I'd replace the cap
do you still need help?
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