Help K8 Gixxer won't rev.

[ross79]

Sold the busa and recently bought a K8 gsxr1000 with 3,200km on the clock.
The thing looks literally brand new.
Today we finally had some dry weather so I took it for a bit of a spin. Went to overtake and found the thing won't rev past 8k!! It was a bit of a shock. Tried other gears and all the same, won't go past 8k. In neutral on the spot it hits redline fine and runs nicely. Running on BP ultimate.
Any ideas?

[99er]

may be a vaccum leak,check fuel pump pressure

[Camel]

clutch lever switch.......

[-M-]

Check for an X-TRE. If it has one, the wrong gear "map" is selected.

[ross79]

Ok. Looking over the bike it appears I'm the first person to lift the tank.
No vac leaks, No tre present, fuel line is not kinked, ran diags and that revealed nothing, also TPS is calibrated correctly.

Don't have anything to check fuel pressure, but from what I've read it appears the FPR may be the culprit or blocked fuel filter.
Will try a cable tie on the side stand switch to see if that might somehow be causing the problem.
Camel, what's the best way to test clutch switch?

[Maj]

try and start it without pulling in the clutch

To test the fuel pump ,
get a piece of wire and strip back the end , push that into the back of the fuel pump relay on the yellow/black wire, and bolt the other end to the battery negative or frame
your fuel pump will now not cycle when you key on it will run constant

now disconnect the fuel line from the tank and slip a piece of hose over the outlet and run it to a container with several litres capacity
then with a timer in your hand turn the key on and measure 30 secs of fuel
if you don't have at least 375ml of fuel in 30 secs your filter is blocked

[DAD]

Also check the quick connector on the fuel line that its fully pushed in.

[ross79]

Ok. Ended up just pulling the tank off. Much easier than the busa, it's only 1 screw on these bikes.
Pulled the pump, filter was a little dirty but pulled the strainer and it's completely blocked. Looks like it has been sitting a few years at the bottom of a rusty barrel. Not sure if I'll be able to clean it enough.

I've ordered a new FPR and filter but they want $40 for the strainer!
Bit crazy when you consider they're only $8 in the states.
Are there any cheaper alternatives to the strainer?

[ross79]

New filter, fuel pressure regulator and strainer in. Just waiting for the rain to stop so I can test it out.

[ross79]

Caught a break in the weather and took the bike for a spin. Still no joy. Appears I've gained about 500rpm but still no power after 8k as it won't rev further!!

My guess is it's a fuel pump now? damaged by the blocked strainer? as now it has a new fpr, filter and new strainer.
I tried ringing for a new fuel pump but nearly fell off my chair when a dealer told me 722!! I can get one here from the states under 500 but even that seams excessive to me.

Maj, do you know if there is an alternative pump that would fit? Overall height of the pump is 79mm and diameter is 35mm.

[pete]

instead of a fueling issue,
could it be something electronic,
something in the ecu?
jat, as it happens in every gear at around 8000rpm.

[ross79]

It is possible, the thing that keeps bringing me back to the fuel systems is each gear it revs less. Ie: 1st will hit 8.5, 2nd 8, 3rd 7.5, etc. Which would indicate either blocked fuel filter, faulty pressure regulator or bad fuel pump. Fuel pump being the only one I have replaced due to crazy cost.
Not sure how you can test ECU as they're coded to the key. So you'd have to swap ecu over with ignition assembly, etc.

[ross79]

Does anyone know if a K9 pump can be used in a K8??
From the diagrams they appear to be the same.

[Camel]

Busa yes, not sure about Gixxer. If its the same part number then its the same pump.

[Shifu]

Busa yes, not sure about Gixxer. If its the same part number then its the same pump.

Just odd thought, What is your rev limiter set to?