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Discussion Starter #1
Sup guys, I own a 2001 929 and the dyno tech had an issue while trying to dyno my bike. First off i have a pcIII, a D&D full system, flapper mod done, and the egcv wired open at the 180 degree mark. While making runs he tells me that at above 9000 rpm it starts losing fuel pressure and he can't figure out why. FPR is brand new and is functioning properly, fuel pump has been checked and is in working order, injectors have been cleaned. Brand new battery, and brand new ngk irridium spark plugs. Neither he or I can figure out what can be the cause of this. That's why I've arrived here to get info from experienced fireblade brothers. Any info?
 

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Just because the Fuel pump is working when you check it, does not mean it is working to its full potential. Things dont always fail completely.
 

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Discussion Starter #3
True, but the tech's notes states that fuel pressure tested good at 60 psi and fuel flow tested good at 160 cc/10 secs. According to him that's what it should be, but the issue still happens at the 9k range.
Side note, i run 93 octane ethanol free gas so i know fuel isn't the problem.
 

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At 9000 RPM, under load (the dyno) you are placing a high demand on the engine, and the fuel flow requirements. I suspect your fuel pump is unable to keep up with the demand at that RPM / load. Have you checked the voltage to the pump at idle compared to 9000 rpm. Low voltage at the pump will reduce the pump's flow capacity, causing the pressure to drop during high demand.
 

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Discussion Starter #7
I haven't done so yet but i will asap. Also after a quick ride the other day i heard a slight ticking sound, which led me to believe it was a valve or something.
 
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