QuestionI have an old Kawasaki RX1000 GPz. It runs smoothly at high speeds, but splutters on low speeds. I have taken it into numerous bike shops, but the same problem reoccurs. While on idle and at low speeds it appears as if all cylinders are not firing. What is strange is that I have a stop valve which I switch off just before switching off the bike. When I do this the bike runs better for a short period of time and it revs better (as if all 4 cylinders are functional) Could this be that the carbs are set too high and are flooding?
AnswerGreat classic bike.
It sounds like the carbs and possibly more needs a little attention.
First I would check valve clearances (unless that's already been done) and electrics (with a multimeter).
Then I would look at the plugs to see if there's one in particular which is fouling or running too clean (too lean). That's likely the problem. You may have a sticky or leaking float valve which is allowing too much gas into the float bowl. This gas boosts the mixture and will cause fouling and misfires.
You will likely have to remove the rack of carbs and clean the bad float valve (replace the o-ring too).
If you go through the trouble of removing the carbs then you have the option of really giving them a complete rebuild. Up to you.
Here's some links to some of the steps involved. It's for a different bike with different carbs but some of the parts will be similar:
http://www.thegsresources.com/gs_carbrebuild.htm
http://katriders.com/vb/showthread.php?t=63344
I'm sure there are similar pages for Kwaks but I'm Zuke guy so that's what I know.
