ZXR750K1 flatslide jet anomaly?

Hi... am new here & hope someone with more knowledge than me can shed some light on this...

I have an original ZXR750K1 which hasn't been started for 3 years (I know it's sad, but genuine reasons)

Anyway, I am working through it mechanically now with a view to getting it up & going again, and during the course of cleaning out the flatslide float bowls (& jets, needles etc) I discovered that the main jet for the cylinder no. 4 carby has a no.75 stamped on it, whilst the other 3 carby main jets have no.138 stamped on them.
Other than this anomaly, all the other jet sizes are the same.

Eyeballing the sizes of the main jet orifices, they both (75 & 138) look exactly the same, and all have the Keihin "star" mark stamped on them. The bike ran without problems when last ridden & there are no other indications of individual cylinder issues.

So... anyone know why no.4 might have a different no. stamped on it's main jet???

Thanks!
Jason

Its probably been jetted & the shop didnt have 4 matching jets, so they drilled a 75 out to 138.. You would really see the difference if it was a 75 compaired to a 138.

Have a look here mate

http://www.duncanracing.com/TechCenter/ ... etting.pdf

http://www.carbparts.com/keihin/needles ... r_carb.htm

.75 will probably be an OEM Kawasaki part, the others will be Keihin replacements