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OK heres the deal. I have a 97 CBR900rr. Sitting for 3 years. I cleaned the carbs, sync'd the carbs, startes the bike. Bike runs off choke at 1100 rpms with mildly rough idle. Pilot screws are 3 turns out. Dies with even a little choke. same with 2.5 turns out. Choke works great one full turn in, bike dies if given any gas. Gotta have bike runing this weekend.
 

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Oh boy.. Sounds like an accelerator pump problem, but given you had the carbs apart, could be a number of things - jets, needle valve (and height) come to mind. Doesn't sound float level related (that usually is either too lean or too rich).

The accelerator pumps (there's one on each carb) overcome a problem that happens when you first crack the carb open. Carbs work off the Venturi effect - a low pressure area is created by the throat of the carb being constricted, which in turn causes fuel to bleed in from the float bowls, metered through the jet, and mixed with the incoming air inside the carb's throat.

When you first crack the throttle open, there isn't enough low pressure to "instantly" pull fuel into the airflow.. Thus, the accerlator pump was added - when you open the carbs, the pump squirts a small amount of fuel into the carb, achieving the same effect mechanically.. For sure your linkage attaches to it on the outside of the carb somewhere (and as I don't know your motor or have a manual, I can't get specific).

This is the place I'd start.. I would make sure all the accel pumps are all hooked up via the linkage and working properly. I would also make sure that when you crack the throttle open, you see a small amount of fuel being pushed into the carb (I don't know where the pump injects the fuel into your carbs - usually there's a small hole from the pump to the carb's throat).
 

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Could be - I don't know the carbs.:idunno: Are your carb slides round or flat? If round, good chance it doesn't have the pumps. If flat, good chance they do..

In any case - let's say there's no pump. You should re-inspect your cleaning. Start looking at your needle valves and diaphragms. (Unless you have direct-lift slides - that's a nice $$$$ add-on.) If the diaphragms are not seated properly, or leaking in any way, the needles won't lift properly. Re-check the needle operation and make sure that nothing is blocking the needle or jet.. Also re-check your pilot jets (the smaller one) - it's there for low-speed/idle operations. If it's clogged it'll definitely impact your idle-to-run cross-over.
 

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They don't have pumps (if they're stock). When you had them tore apart, did you try and squire carb cleaner up through pilot jet to check for clogged passages? There should have been a strong stream exiting a small hole right in front of the butterflies. Spray the pilot jet hole, then install pilot jet and remove mixture screws, should be spray coming out mixture screw holes. Finally, spray through air hole in the back and make sure it gets all the way to the hole in front of butterflies. It doesn't take much at all to block these passages.
 
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