[bjl4776]

I picked up a 08 250r that was wrecked as a project bike. Bike had been sitting for a long while and didnt run when I purchased it but had good compression. I rebuilt the carbs and adjusted valves to the looser end the specs. Bike had a slip on and factory air box when I got it. The carbs werent too bad but i went through everything, had stock jets, no shims, and correct float height. Got it all back together and it started right up but was running rich at idle and until about 5k, then it would break up a bit uptop. At this point I already knew I was going to have the carbs on and off so many times I removed the stock airbox for a k&n 0990. Put it back together with 3 shims per and found it ran good until bout 9k and it would break up. Checked plugs, too lean. I know I need a jet kit after removing the stock box but I decided to play around in the meantime. Started adding 2 shims at a time until it pulled hard to redline with 7 shims. But with 7 shims it was running way to rich down low and would flood coming down to idle after running it hard. I went back down to three shims and used "tuning" tape to cover the airfilter until it pulled good to redline. At this point I thought everything was good and went for a long ride. Bike ran great while it was cold and always pulled hard to redline. After riding for a bit it was good and hot I got stuck in some stop and go traffic and she was flooded. Wouldnt rev past 2k and if I let off the throttle she would do. After a few engine starts I got her to clear out and rev fine in neutral. When I would goto take off she would bog again. I would have to slip the clutch keeping it at about 5-6k to keep her goin then it would pull hard to redline but problem would repeat when coming to a stop. I tried removing some tape to a point where it was breaking up a little up top but still had the same problem down low At this point I just pulled all the shims out and put it back together but haven't tried it out yet. What could causing it to be running so rich down low even though im leaning out up top.

Also, even when the bike isnt fully warm and running pretty good sometimes it would stall out when coming to a stop if I dont keep the throttle cracked. Idle has been adjusted by opening idle screws till highest idle rpm is achieved. Smoked tested both carbs for vacuum leaks and didnt find any leaks. Secondary air has been removed and capped. Crankcase vent has replaceable filter. Fuel is 89 octane with stabilizer, fuel filter installed.

I am a L1 BMW tech and know fuel injection like the back of my hand but this is my first in depth use of carburetors. I have a wideband 02 sensor laying around. Im about to weld a bung in my exhaust and ride around with a laptop in my backback and datalog it.

Any help is greatly appreciated,
Thanks
Brandyn