Sounds like the sustained high speed might have sucked some trash into it. Or there's hole in the diaphragm. Its purpose is to hold a "valve" open so fuel will flow for as long as there's vacumn applied to it. Insufficient vacumn, no -- or slow -- fuel flow.
I would pull the tank and drain it, pull the petcock and disassemble and inspect the parts very carefully. Use a magnifying glass if neccessary to inspect the diaphragm for a split, a pinhole, or a tear. Clean the nylon screens meticulously. There are two -- one in the bowl and a "sleeve" that fits over the feed tube. And inspect the o- rings, also two -- one in the bowl and the other secures the sleeve at its base in the throat of the petcock. Check the vacumn supply tube from the engine to the petcock for leaks. And clean everything twice. Regardless of what you do or don't find, I'd install a rebuild kit. They're about $20. Your bike's 30 years old and the rubber's tired. -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en.
