Installing Aftermarket Fuel Pump on ZX10R

The Crim had been developing a problem with losing power at full throttle which got worse as the speed rose. It was really noticable recently when doing some high speed stuff under controlled conditions (HG ). The power loss felt like it was hunting or surging and only seemed to happen from around 1/2 throttle to full throttle. In other words I could get it up to fairly good speeds with partial throttle i.e. 180-230km/h, but as soon as I opened it right up it went to shit. At lower speeds it was noticeable, but not quite as bad.

I had my suspicions that it was something to do with the fuel pump, particularly because since I parked it into the mound of dirt, the pump was making all sorts of strange noises.

I pulled the pump and gave the filter a good clean as it was filthy, but aside from a slight improvement it didn't really help. Once it was back in I took note of the volume of fuel it pumped out during its 4 second prime. According to the manual it should be over 72mL, I was getting anything as low as 50mL

A bit of research on ZX10R.net showed that there were a few others who'd had their fuel pump go and given how costly a new one was for them (AUD$300 in the states), they'd used an aftermarket Walbro GSS 342 fuel pump instead. It wasn't a straight swap but had solved their problems.

I checked out the cost of a new pump from Kawasaki Aus and they wanted $595 for it!!!!! and the yanks thought it was expensive for them.

So plan B came into effect and a Walbro pump was purchased on ebay for the princely sum of $165 delivered

Time to hit the garage.......

So the pump arrived and I got an afternoon in the garage to get it installed.

Shiney!!!!

First I had to pull the old pump out of the tank...

As you can see, the actual pump is buried in the middle of all the other bits...

Next step is to pull it all apart to get to the pump and as you can see, the new pump is a bit bigger and not exactly the same at either end, so there'll need to be some modification to shoehorn it in there....

First up the tabs on the end were dremelled off, followed by a fair chunk of the rubber in the middle of the black bit.

Then the pressure regulator needs to have a bit of the tube on the bottom of it trimmed off to allow room for the plug on top of the pump...

before

after

There are a few other bits that needed a bit of adjustment too which I forgot to get photos of but basically they are the bits at the top of the pump that go over the outlet to seal it where it goes into the regulator assembly. The pump overall is longer than the stock one, but with a bit of adjustment it has fitted in there snugly.

The other thing that needed doing was to solder and heatshrink some terminals on the wires for the pump so it can be connected up.

The end result...

So with a bit of a wiggle it fitted back inside the tank, I plugged it in, attached the fuel line and gave it a prime. No longer do I get an anaemic squeal...much more of a purposeful whir

The two big tests are how much fuel it delivers when it does it's 4 second prime and how it goes at full throttle. The prime now delivers approx 90mL of fuel but I haven't really had a chance to test the full throttle high speed stuff yet.

Initial impressions on a quick blast to work and out for lunch is that it has gotten rid of the hesitation that had crept in when first opening the throttle and it's back to ripping your arms off as soon as you crack it open

Nice work.. luv a bit of garage engineering..

Good work! You can afford to do this three times before you break even with one factory pump!

Good work Mick. Nothin like saving a bit of dough with some fettling..

Well I figured if worst came to worst I'd stuff it up and end up having to buy a new one, and then I'm out of pocket $760 instead of $595, which doesn't sound anywhere near as much a difference (especially if you say it really quickly)


....but it's a shit that you can't buy individual parts for the whole fuel pump assembly, you're only option is buying the whole thing


I forgot to mention that the ebay ad says that these pumps can support 500hp, so my bike must have 500hp now!!!!!!!!!

I forgot to mention that the ebay ad says that these pumps can support 500hp, so my bike must have 500hp now!!!!!!!!!

Still not as much midrange as a 9 though

Good one Mick . Thanks for the info .

I forgot to mention that the ebay ad says that these pumps can support 500hp, so my bike must have 500hp now!!!!!!!!!

Still not as much midrange as a 9 though

Yep and its easier to fit an aftermarket fuel pump to a nine as well