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Need carb tech please

2020 Views 27 Replies 8 Participants Last post by  Gpz 1100
I have a Gpz 1100 all stock and it sat for years and only has 4500 miles on it. Tore down carbs and replaced float needles and went threw all carbs and cleaned. So bike idles and there is no mid range it falls on its face and if you roll throttle easy it鈥檚 ok. I鈥檒l put new plugs in and run around the block and they are black. Running rich. ????? Needle is stock and can鈥檛 move clip. Jet is stock smallest they have. Compression is same across the board. All plugs are black across the board. Any ideas I鈥檓 pulling my hair out with this bike. Please help
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Side thought... does this bike have a filter installed? If so has it been checked out, for fuel flow with and or with out?

Carry on thought I would throw that out there.
Open the throttle until it just starts stumbling and spray the boots and intake area with carb cleaner. Possible vacuum leak.
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Possibly oil fouled spark plugs? Maybe rusted cylinder walls allowing oil by? Possible weak ignition system?
I'm all out of ideas. :confused:
I have removed intire air box and cleaned and replaced air filter. Absolutely no vacuum leaks. Compression is straight across the boards. Just a thought could the jets I just got which are stock 35 could they be smaller causing bike to be lean at idle ? I checked ignition and all good. I rode the bike when old jets in which I accidentally drilled due to blockage and bike idles with them but not the new ones I bought with the smaller hole in the pilot.
I have brand new plugs in it.
Float level will not have a effect on idle circuit? Sense changed to new pilot jets it willl only idle. Soon as you pull throttle instant stall.
Float level will have an effect on the idle circuit, same as the main - too low and it's lean, too high and it's rich.
When you cleaned the carb, did you make sure the air jets were clear? Too little air into the emulsion chambers will have a big effect on how it runs, especially at idle.
Yes checked all air tubes clear. I adjusted floats at it lowest point. Being as lean is I could get. 16.5 mm. Then went to 18.5 mm and both adjustments were the same. I checked all four small holes in front of butterfly. All clear. Blew out all holes and Ali with carb cleaner.
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