2004 Hayabusa, 2nd gear jolting under hard acceleration

[Hannibal23]

Hello,

I've got a 2004 Hayabusa
Recently had a full gearbox rebuild (six months ago) , also had the top end rebuilt ( two weeks ago) , heads machined, new piston rings,gasket done, clean etc etc. Now just about a week ago. The bike will now jolt in 4rev,6rev,8rev,10,rev when accelerating hard in 2nd gear. I've had this problem before. Had the gearbox and bottom rebuilt which sorted the problem, then a couple of months later it wouldn't rev pass 7,8rev in 6th. Dropped in some very good injection cleaner and loaded the bike up into 6th gear and open full to clean the injectors, which then fixed the problem. Same thing happen about two weeks ago, wouldn't rev about 9rev in 6th gear. Put some good injector cleaner in, problems solved And now again, this time putting injection cleaner hasn't fixed the problem, feels like it does when the gear box went. I've brought this bike second hand and have had it in the work shop more then i have ridden it. I only had the busa for about a year. But there has been problem after problem.

I've had the gearbox fixed 6 months ago i can rule that out, same with top end. It also doesn't feel like it trying to jump out of 2nd gear into 3rd. Feels like there is a blockage in the injection lines or the lines need replacing. I ride the busa, every day in stop and start traffic normally get the usually carbon deposits in the lines, open little throttle before and after you leave for work (clears out the deposits) and ride it hard on the weekends.

My next course of action, will be to clean the air filter, check the fuel tank line, and injection lines.

Other then that i'm not a mechanic, only know how a bike works and generally necessary things, like replace pads, oil change, head lights etc. I prefer not to touch anything major. It has only been at one work shop while it has been with me. Im beyond pissed off , beyond annoyed.
I'm out my wits end.
Please if anyone could help diagnose the issue.

Kind Regards
Hannibal23

 

[sixpack577]

Fuel filters clogging and fuel pumps failing is common on gen1 Busas.
From the sound of things, one or both is likely your problem.
Especially in all gears, having already had your trans undercut, and it not revving past 8 or 9k rpms.
There are "how to" threads on fuel pump and filter replacement here.
Not a big deal since you can do those other things you mentioned.

 

[Samaki]

If you have a Power Commander installed I would suggest removing it and see if it performs the same. The PC connections into the harness are less than ideal if you use the cheap little splice connectors with the kit. It should be hardwired in for reliability.

 

[Kevin Jones]

Do the fuel filter bypass, I think its a sticky on here somewhere. It doesnt really cost anything and you dont need to be a mechanic. That POS filter/reservoir will clog up and you see a thread about someone with a similar situation once a week on here. Even if that isnt the problem, it is a good solution to a bad Suzuki design. Here is a test you can do. Prop the tank and take the fuel line off. The one that goes to the rail. Make a little cheesy hose to get the fuel so it doesnt spill on the wiring and stuff. Shove that line inside or somehow make that line an extended line so it goes off a few feet. Unplug the electrical connector to the pump. The yellow/red stripe (someone check me on that) is the + and the ground is black. Take some alligator clip leads straight from the battery, put small pieces of paper clip on the ends that you will insert into the plug to touch the male connectors of the yellow/red and black and cover the rest of the clips with electrical take so only the tips of the paper clips are exposed metal so as to avoid any accidental sparking. Basically you are putting 12v right to the pump with the line going into a measuring container. Have a buddy with a timer hold the line into the container so as not to spill as you hold the leads onto the pump, essentially hotwiring the pump for 30 seconds. See how much fuel is in the container. The container should hold at least 60oz. Its a fuel volume test and will tell you exactly if your filter is clogged. You should have 40oz of fuel in the container at the end of 30 seconds. I bet you dont.

 

[dadofthree]

to the oRg

If it's second gear only, get ready to have the tranny worked on and get second gear undercut, if that's what happens.

 

[ky busa]

 

[ajones1976]

bent shift fork will cause the saving gear not to engage properly.. then you get the jerking.. it's going in and out of gear. #1 culprit. . shift fork. I'm fixing mine now