My brother has a ’98 Kawasaki Ninja. He got rocks in his carb after putting down his gas tank on some pebbles. He cleaned them out, his bike was continuously flooding, he replaced the float bowl valves, still flooding.

I drive 5 hours to fix it for him, he had his needles in wrong, so it wouldn’t start, I fix that, it starts. He drives it, one of the pilot jets vibrates out because he took it out for some reason and didn’t tighten it. Put it back in. Can’t get it to start again. At this time, it is too rich to start, my brother was being stupid and light a lighter trying to start it, and it could literally sustain a 2 foot long flame from the unburnt gas fumes from out of the exhaust.

I take the whole thing apart and put it back together, cleaning it very thoroughly, I didn’t have any brushes, but I sprayed carb cleaner everywhere, made sure it was all on tight. The only thing I couldn’t make sure was in perfectly was the left diaphram area since I couldn’t get the cover off due to a stripped screw. He doesn’t take very good care of stuff like that. The right diaphram is tight and sealed in it’s seat. The needles are on correctly, already did those before.

I start it up, it works again. Won’t idle, dies very quickly if I don’t give it gas. The right exhaust has white smoke, lots of it. Left exhaust looked fine. After about 30 seconds of running, then continues for a while after being turned off. Very rich still.

I go to replace his spark plugs, he’s using CR7HSA’s, you’re supposed to use CR8HSA’s, the 7′s are what I use up in Flagstaff, AZ, during the winter, when I can’t get my bike started because it’s 15 degrees out. I replace these, I get it to idle and I get it to start fine. Smoke is gone. One thing though, while I can smell gas, I know it’s very rich. The old plugs didn’t look rich at all. They were dark around the bottom portion, but the top of it was grey, a bit rich, but mostly normal. They were properly gapped, not oily, no debris, nothing wrong really aside from the part number used. New plugs are properly gapped at about .675 mm.

But it still runs very rich. After taking a ride on it, I literally smell like gasoline from the exhaust itself.

The idle mixtures are all the way lean, the float bowls are lower than suggested (which I read may make it leaner). Needles are stock, jets are stock. Float valves work, airways are clear, needle doesn’t stick, jets are clear, they’re not sync’d but they look close enough by eye. I will sync them if it needs it, done it before.

He did have a problem before all of this, said he was getting a bit of a rotten egg smell, and it was a bit rich. If anything, it’s back to what it was before him getting rocks in there. just trying to improve it for him so it doesn’t break down again.

I actually own the exact same year of bike, worked on it for a few years, redone almost everything on mine, and mine runs great. I’ve gotten his to the best condition I can, now I need help, is there anything else I can do to make it leaner?

Sorry if my question is long, figured I needed to explain everything to anyone, to give a better picture!

Thank You.