If you're a throttle jockey and whack the throttle on and off quickly ...... the ONLY solution is to go to a smaller carb which maintains vacuum and velocity better ........
Check out what sized carb 65 to 70 HP Jawa 500 cc speedway solo racing engines run ... a 34 mm Delorto !!!!!!!!!!!! And they run that sized carb because they can't afford to have the engine bog , hesitate , cough or sputter when they pitch it sideways into turns at over 160 kph then feather the throttle to keep control of the bike ..... The rear wheel MUST be kept spinning all the time or the rear tyre bites , the bike high sides and throws the rider off ...... A big carb simply won't work with a quick turn throttle unless the rider slows his right hand down ..... The throttles are designed mainly so that you don't have to rotate your wrist so far to get to full throttle to make it easier to hang on and concentrate on controlling and steering the bike under max power ....
Description of JAWA Engine Type 884 and 888
Also ... check out the main jet run with METHANOL on a 500 (a # 230) ......... I read on Planet Minis where one guy was advising people to run a # 240 main in a Mikuni VM-26 on a YX 150 bored to 165 ....... and they call themselves tuning "experts"
VM26 snap crackle bog at 3/4 to full throttle - Planet Minis
Errrr ..... and when you go up above sea level ..... you usually go down in jet size .....
Rocky Mountain ATV Club
Rocky Mountain ATV Club