Kawasaki Sportsbike Riders Club - Australia - Online Forum

Hello all.

I have a question that I'm hoping some expert out there can answer regarding the 39mm Keihin FCR Flatslides that I have fitted to my ZXR750?

The long story very much shortened is that one of the twin accelerator pump fuel one-way check valves isn't blocking return fuel flow back into the float chamber. Initially both accelerator pump check valves weren't blocking fuel, but one has started working again following a lot of carby cleaner and encouragement.

Anyway, this check valve (or shutoff/non-return valve.. whatever you want to call it?) is a nylon looking thing located in the accelerator pump inlet passage on the underside of the float bowl. It looks looks like a restrictor in the passage, but obviously there is more to it than that? I can't seem to move it in my feeble attempts (VERY limited access & not wishing to cause any damage) and am not sure if it supposed to be removable at all? It sort of looks like it is pressed in?

If someone out there is still reading this thread & thinks they have an idea.... I'd very much appreciate it?!

Jason

found these
http://www.thumpertalk.com/topic/196617-tuning-the-keihin-accelerator-pump/




any help

Yes... thanks, that is interesting. What I am calling a check valve they are calling a leak jet.

In my case, I don't have what looks like a leak jet (with an orifice) but rather a square nylon looking thing that appears pressed into the circular passage from the float bowl to the accelerator pump chamber. I guess it could work the same as a jet, with fuel flowing around the outside but it doesn't sound quite right to me?
Also, one of my "leak jets" only allows fuel to flow in one direction (into the AP chamber) as I think it should, but the other one allows fuel to flow in both directions which I think it shouldn't?

Anyway.... I'll keep soaking them & searching for info.

Thanks