Have a 99 Honda CBR600 F4, bout 45k..... Purchased it almost 2 weeks ago, Well kept apparently & looked like it hadn't ran in quite a while. I'm a country boy so yes I'm very mechanically inclined & a bachelor's degree in common sense.....lol......anywhoooo, My machine is doing the EXACT same thing .....of course I took off pair & LEFT the 2p just hanging, Tee'd exhaust valve reads with a pitcock drain valve ( "crackle" adj ) .... inner carb vents tee's was removed n naturally venting ( along with valve cover crank case vent hose free ventin/Outer diaphragm vents tee's to breather box per non cali diagram & all other box vents closed off & vacuum supply t running from carb to evap controll valve blocked..... evap is removed also..... Bypassed fuel cut off relay and fuel Transfer to run when key comes on per jumper the blk/bl wires.... Replaced fuel transfer pump with Holly Many fuel pump which is 2 to 7PS side good up to 500 HP.No filter cause Use prescreen on tank fill... Same original Original coil packs , with new E3 plugs..... Now common conventional naturally aspirated engines want air Air ..... the easy part is shovein air down its throat helps combustion rate blah blah blah, dumping fuel @ the correct ratio coinciding 4 carbs This is sweet spot. But like you said 1st 2nd gear up to 8-9 grand or 55-60 miles an hour does like its supposed to then Acts like there's a safety feature or something cutting it off. I know it's not the oil because the light never comes on and I have tested it it is working great. ETC works,, tps Nothing that should warrant That happenin..... Has new battery and check the regulator/rectifier and it's working fine..... However we instructed behind a truck while trying to test drive and figure this out, the air was taken off the front of the machine and it seemed to pick up but when I came around it fell back flat on its face.. I got to thinking what if the air that's come through the DAi Creating or shoving air into that the Diaphragm Vents.... So I doubled up the white cotton filters and put a small hole In a screen restriction apparatusSo it wouldVent without beingInfluence with the DAI...... Seem to get a little better but comwas still a huge issue. Out of frustration I took my hat off n stuck it into the front ofOf the cowl, blocking it of n ####BOOOOM SHACKALAKKA..... 85 to 90% Of the machine's power. Taken into consideration I've yet to sync the carbs cause waiting for gauges...... haven't gotten it At a 100% because it's still hiccups in stutters, especially if the wind is blowing really hard straight at it..... My main burn brain is This is the year before the deadline Jackson, it's naturally aspirated Just like a pump carb or such.. Looking through the schematic I didn't see anything relevant that would cause a regulation in my prior for/RPM like it was doing Looking through the schematic I didn't see anything relevant that would cause regulating my mph /rpm like it was ACTING LIKE..... As for the DAI messing with the Chamber venting,,,,, I could see a little bit of Happening on paper, witness It happene on the bike myself...... think another tailed sign was there was a lot of residue on the inside of the airbox carburetor side, as if it was getting blown back out the carburetor...... But like I said, it's not a 100% I could use all the help I could get. Cause I'm about to go bloopy Over not figure This app. ConventionalMechanicalWisdom tells me How to feed the beast. In short.....wanna Shove air & fuel .....More fuel more oxygen, easy in, easy out equals horsepower & performance..... As far as I know everything is stock in the carburetors k&n air filter with the FMF slip on exhausts..... Any and all help be greatly appreciated

 

OP has F2 and you've got F4. Might be good idea to start your own thread to not get them mixed up.