Hi folks! Long time no post! I've been out of the riding scene for years, and browsing my old posts brings back a lot of memories.
Anyway, there is a 2004 'Busa in my shop that was traded in, and a co-worker wants to buy it. First we had to put fuel in it, as it was out of gas and wouldn't start. I took it for a spin and it bogs really bad, sputters, jerks, and it never really put out any power even if it seemed to smooth out at higher rpm. At a stop in neutral, you can open the throttle at any opening and it'll sputter and bog, no throttle response. Open wot and it'll bog and eventually snap to higher rpm.
The bike is stock with 20k miles except for a k&n filter as far as I can tell, even has the stock airbox flapper. I pulled the plugs and they look decent, but very white, which makes me believe it's getting little fuel. All 4 exhaust pipes are heating up. No FI light is on. I have not tried to pull codes. What I did find that seems to help, is unplug the vacuum line from the MAP sensor. 'Course it doesn't want to idle then, but it'll throttle up and rev, and make my d*ck hard (...memories...) with that line off. That should make it run richer in that state, and it runs much better. I installed a different MAP from my old parts, and it didn't help.
Any suggestions on what to try next? I have limited time to punk around with it, unless I want to stay late at work. I'm suspecting a weak fuel pump, something clogged in the fuel system or a wonky sensor. I'll probably check the TPS (throttle sensor), and end up checking the fuel system.
Thanks!