3000 RPM surging

rob702

Registered
Help my 2005 when riding below 3000 rpm feels like the bike is surging and if you open the throttle the engine seems to miss before taking off . I can go back to the bike a hour later and the bike will run and ride perfect
When the fault occurs the idle speed drops from 1200 to 1000 rpm and the engine feels uneven
Fault happened today as I was riding home so I took the plugs out and all four Plugs were dry but completely black

List of thing I have tried up to now
4 new plugs
Change all 4 coils
Had injectors cleaned and tested
Balanced T/B
Changed all vac pipes
Any ideas will be much appreciated
Thanks Rob
 
My mileage is 13000 and mods are ti force 4into1 small air box mod and re-mapped but this was done a couple of years ago and the has run great until a month ago could it be the fuel pump ? When I got the bike it had been stood for 3 years and had a lot or surface rust in the tank
 
Is the flap in the airbox OK...had the diaphram on my old 03' bike fail and the engine wasn't happy

Fuel pressure regulator...has it been checked.
 
I have the same problem. So I hope you figure out a solid answer. All I have is slip on dual Yoshi. About to add a PCIII. Between 2.5k and 3k is where I get it.
 
How did you address the rusty fuel tank issue? My latest Busa acquisition had also sat up for some time, and had what I would have described as "surface rust" in the tank. After pulling the tank, and before all was said and done, I had removed probably close to an ounce of "loose" rust. I then treated what remained by filling the tank with five and a half gallons of "Metal Rescue" for a 15 hour soak. Judging by how black the liquid was post soak, I'd probably removed that much rust again. If you haven't already, you might want to look at your filter, and or pump.
 
Its under the tank,,you have to drain fuel,,remove tank and turn tank upside down...its the black plastic unit inside with float hooked to it...problem is they didnt make it a cleanable filter...and new filters run (entire black unit) runs $250-$300...there has been a few ways around it by drilling out filter and running inline filter..and theres a fine screen pickup also that cloggs attached to black unit inside...
 
I stripped the fuel pump today and washed the filter in a bowl of fuel lots grit and little specks of rust came out and the strainer at the bottom of the pump had lots of rust stuck to it. Put the bike back together and went for a ride, bike seemed OK so think I need a pump or a filter. The dealers want £267 ($447) for the filter so think I will look for a second hand pump does anyone know if a gen2 pump will fit as they seem to be a lot cheaper than an intank gen1 pump ? Also could anyone explain why a block filter would make the bike run so rich I would have thought it would make the bike run weak
Thanks Rob
 
I stripped the fuel pump today and washed the filter in a bowl of fuel lots grit and little specks of rust came out and the strainer at the bottom of the pump had lots of rust stuck to it. Put the bike back together and went for a ride, bike seemed OK so think I need a pump or a filter. The dealers want £267 ($447) for the filter.
Thanks Rob

Good to hear you've got things sorted, but that's WAY too high for the filter. You might check with the sponsors here on the org to get some realistic pricing.
 
My bike has similar symptoms... I look in my tank and it looks good from the top. On yours could you see that there was rust in it?
 
Basically its not as smooth as it was before. When I just crack the throttle the bike surges forward. When I am trying to just maintain my speed and the RPM is below 3k it lurches forward and back. God forbid I have to roll on to the throttle in a turn under 3k. Its pretty unsettling. Any idea what the problem could be?
 
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