i have a problem i cant seem to get this thing to idle smoothly. i have to play with the choke all the time. i adjust the two screws on my carb ( see attatchment) back and forth and cant seem to get a good starting point. one i think i have it down it bogs out when im riding and then i have to play with the choke ( press , depress) constantly to get it to go. the last thing i did was change the fuel filter and air filter.