Busa Spuddering At 5000 Rpm Under Hard Load

[Hitman wffw]

I have a 2000 hayabusa with a 1397 big bore kit and I did the ecu fly wheel swap .. I would go out and the bike is good under a small load but if I was to dumb the throttle it gets to 5,000 and bust up.. I changed fuel pump to a inline pump with new regulator and changed TPS sensor .. I found out the injectors where very dirty we cleaned them and the bike sounded a lot better but went for test ride same issue.. I don't have a pc3 but my ecu is flashed . I am lost for words don't know what to do need help bad

[omally]

Hi bud im new to Busa's and ive been thinking of a big bore job what this about a fly wheel swap I assume its the norm

[Hitman wffw]

Well i have a 99-00 busa which has the 16 bit fly wheel.. but the 01-07 I believe has the 32 bit fly wheel which sends more spark thru the ecu which makes it run a lot better check it out

[over200]

It sounds like fuel delivery for sure, I had a very similar issue and it was the aftermarket fuel/ ignition kill switch. Zip tied the plug into switch and problem was solved. I have a FBG tethered switch for LSR.

[omally]

Well i have a 99-00 busa which has the 16 bit fly wheel.. but the 01-07 I believe has the 32 bit fly wheel which sends more spark thru the ecu which makes it run a lot better check it out

Thanks for the info ill try that ;-)