First of all, you really need the correct X and Y pieces in the powerjet setup for it to work properly.

Second, the pilot jets were a big issue for me. The entire time I lived in Japan, I used only #35 (smallest size available) pilots both when my engine was stock and after all the mods and overbore. The airbox mods tended to make the pilot circuit run richer, and even with a 35 I was sometimes too rich. I am now living in an area that is typically higher air pressure and much less humidity, and am running #38's. Keep in mind, though, I am still using the oil injection system.

Last of all, check a few things on the bike. Make sure the compression is up to par. If not, that could be a problem. Also check the reeds and make sure they are sealing properly. Deteriorating reeds can really wreak havoc on your jetting. Check the wires to the coils for corrosion, also, they seem to be a problem with alot of NSR's (luckily I havent had any issues).
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Paul Herr
'88 FZR4/GSXR/YZF Frankenbike
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