needle height issue?

[Steggy43]

I took my race fzr600 1990 3HE out for its first shakedown test yesterday, and for the few laps i did (due to an oil leak), the exhaust did seem to pop at times and the bike felt loud for a short time around 3/4revs approx, apart from that it seemed to run fine. The main prob was riding around the paddock before heading out to the track. It really coughed and spluttered and I really had to rev it high to keep it going. This makes me think the problem is on the needle. I took the carbs apart and found that it has what looks like factory pro needles on clip 4 from the top with 3 washers under the clip. one is small diameter which probably came with the jet kit, one is slightly larger diameter and one is very thick plastic.

As I bought the bike with this setup, I have no idea of what is standard and what a fpro/dynojet kit should be set to start with. Does this sound right to you guys. Unfortunately I dont have time to dyno it before its first race which is this weekend.

The engine has a skimmed/ported head with 1mm oversize pistons and reprofiled cams and I have K&N pod like airfilters on the carbs with no airbox. I am racing this bike in the uk.

Any comments will be much appreciated.