Fuel Pressure Woes

[Terminator2]

Looking for some input. Smelling some fuel vapor (unable to locate source). Riding the bike up a mountain, attempt full throttle and bike starves at 6800 rpm. At home, I warm up bike, able to rev to redline. Idles properly. Installed fuel pressure gauge. Key on....58psi. Engine start/run...50-55psi with fuel gauge bouncy needle. Key off, immediately drops to 45psi. Quantum fuel pump has 30k on it now-5 years old. Volts to fuel pump 0.5 volt less than at battery engine running. On the freeway she'll rock n roll.

I am only a 'B' student, so all of you A+ feel free to chime in . Appreciate your input. Hope all your riding days are going as planned. Thanks, Rick

 

[Sadlsor]

Have you cleaned the carbs?
Oh, wait...
Nah. I got nuthin'.
But I'll follow this thread to learn something.

 

[Andrew Shadow]

Since you installed a Quantum fuel pump the first thing that comes to mind is the issue of the inferior in-tank fuel lines restricting fuel flow that has been reported. Did you install the quantum fuel lines?
The fuel pressure is within specification but that doesn't mean that the volume being delivered is. The specs for that test are in the manual.
Based on your fuel pressure readings it doesn't appear to be a fuel pressure problem. It seems to be more of an engine management issue. It can be as simple as a dirty air filter. At higher elevation more air volume is needed to achieve the same result. The effects of a badly restricted air filter become more evident if that extra volume can't be fully realized. It can progress from there to anything that affects the ECM's ability to correctly read and adjust for current circumstances like a blocked 5-way Tee, a failing map sensor, blocked fuel vent lines, charcoal canister vent blocked, etc.. You didn't state anything about trouble codes so my first recommendation would be to check to see if there are any trouble codes stored if you haven't already.