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1990 Zxr400-H2 running rich no matter what i try

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1990 Zxr400-H2 running rich no matter what i try

Dunno why but this thing is always burning rich.. Set float height at 11mm, no needle seat leaks..

2 1/4 turns out, cleaned carbs few times.. Floats not sinking..

New plugs, wires..

Main jet stock at 98, stock pilots at 35..sea level.

So I machined new needle seat sleeves and presses them into old needle jets.. Seems to have helped a bit.. But after a 200 mile ride today still black powder on exhaust..

Fyi I added diesel injector cleaner.. I need to double check but after I 00 miles I wiped exhaust inside again and it seemed to be much cleaner after second half of my trip..

Installed new rings about 300 miles ago.. No rebore, just new rings.. Bore had no groove at all..

I have valve seals as well, but havent fitted cos its black dry powder indicating fuel not oil so ruling oil out, besides doesn't use a drop of oil far as I can tell..

Should the Needle be totally seated at idle? Bear in mind this bikes needles sit inside a brass tube that has no emulsion tubes.. It somehow criss crosses with main jet and emulsion tube..

Shd I reduce pilot jets?

Also according to factory pro these are very rare carbs where the mixture screws sit engine side yet are in fact air screws... That true?

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