Hello! Newbie here, needing help with carb i have 2003 road king CV 40 carb engine is stock except for a hypercharger pro r series air cleaner and Vance and Hines true duals with thundercones. i am running the sportster needle with 195 main and 48 slow a/f screw turned out 3 1/2 from seat it had drilled vacuum port hole drilled to 1/8Th and yost kit i replaced the slide to a new slide no drilling and stock emulsion tube basically back to stock except for jetting. seems at anywhere from 40 to 60mph i can open throttle and it seems to pull some but not like i think it should has like a rough /stuttering feeling trying to excel up it takes off great from a dead stop and through gears great but at normal mid sucks when opening throttle wide open to pass or just get up speed is there something in the mid need to be changed? drop jet sizes slow and main or would the thundercones have something to do with as i read about those needing to bend tabs and such. any help would be appreciated. the jet sizes where reccommended by yost tech with their set up, he says exhaust i have may need bigger slow and back out to 3 1/2 that's where i left it after taking out their kit and still same results as it was with there kit. thanks

 

That sounds like the sort of problem you could chase around for a long time and get nowhere! Frankly I would visit a local indy to see if he can help. It is impossible to diagnose problems like that on the internet, without seeing and hearing what is going on!

 

yes i hear that i,m burnt out on jet changing gonna get me set of andrews tw21 cams and install then take in for fine tuning which i think i need to get the most out of them thndercones with the v&h dua head pipes thanks for the in put