Irregular acceleration/revving

[markv3719]

Thanks for advice on a checklist to overcome folowing problem:
My Monte S2 accelerates nicely up to 3500rpm but goes into a dip between 3500-4000rpm. Above 4000rpm, acceleration is impressively good and even better since I installed a CSC exhaust.
The hesitation between 3500-4000rpm also occured with the standard exhaust and is apparant in all gears.
Can anyone let me know what the most sensible sequence of checks are that in I need to do to find the cause?

Thanks

[DJ]

I'd think about playing around with your carb main jets, emulsion tubes, and air correctors. It's all highly dependent on your particular environmental factors (altitude, etc.)

I can't remember the normal point of transition from idle jets to the mains but the emulsion tubes have a large part in controlling this transition point. My Scorpion had a stumble like you describe and different emulsion tubes (F24, I think) made a big difference.