'04 Stumbling @ 6,000 RPM

[HiYaBruceA]

I have an '04 with Brock street megaphone, Brock top end kit, small airbox mod and PAIR removal. I had it remapped and dyno'ed in September because the engine was missing. After remapping it ran fine for a few weeks but the problem cropped up again: wanking the throttle causes the engine to bog/stumble at high rpm's.

I changed the plugs but the problem remains. An interesting comment was made by the dyno tuner. He said my TPS setting was off, but he reset it. Can the TPS setting move by itself? I set it myself at C00 years ago and carefully tightened the Torx screw to prevent the setting from changing while tightening.

I've seen other posts on similar stumbling problems here that addressed replacing the 'rectifier', which sounds like one of those old construction job practical jokes "Newby, go get the latex rhomboid hypothecator so's we don't have to seal this here concrete." I also read that it could be cam timing, but why would the bike run fine for a while then start bogging down again?

Does anyone have a diagnostic plan that I can use to sequentially locate the source of this problem. I'll start by checking the TPS setting and re-installing the new map. Any other ideas?

[suzuka1980]

injector problems

[HiYaBruceA]

Originally Posted by suzuka1980

injector problems

No, found out yesterday it's the fuel pump. I will be on my third, for an 04 with 46,000 miles on it.