Ive got a DS with a flatslide(TM) with a clamp-on K&N and I need some help on jetting. Its got a 11.5/1 so I run supreme and it runs fine but if I lug it and gas it hard it misses. Does anyone have a simular setup. Im at sea level. Its got a 40 pilot and a 142.5 main with the clip in the middle. Anyone got any ideas for me. Took acc pump off and didnt help. Its seems nothing helps.

 

I know everyone gets tired of the jetting questions but its killing me. Any help would be great.

 

What size is the new carb and what was on there. Its possible, when going to a larger dia carb, the velocity of air slows down, and he torque goes with it.
Try pulling the choke on while it experiences the flat spot, and if it gets better, then its too lean.
Try pulling the air box lid for another run, and if its better, then its too rich.
Usually a miss indicates a lean condition. If you are at partial throttle ( less than 3/4 open), try richening up the needle.
Heres an article on jetting and symptoms.

jetting

 

When I used to run the TM45 carb in order to eliminate the hesitaion I had to turn the pump nozzle squirter so that it would squirt directly at the needle. This would keep the solid stream of fuel from entering the chamber and break it up to mix with the entering air.

 

Thanks Ill try that.