What main jet size do i need for 70cc kit

hello i have a 2000 yamaha bws with athena 70cc kit and sport muffler what main jet size is needed?? right now i have a 92 sized jet but the scooter dosnt run good at all my carb is the original one that came with the scooter!



alright thank you for the info i have the lighter rollers in the bike with a sport filter but i will change the jet! i find the scooter takes off alright then it just dies down on us!


thanks for the help

hi there

if your still using the standard airbox id recommend changing rollers to a lighter set all depending on how you scooter responds as now the 70cc kit provides power over a wider range maybe the easiest thing to try at first, if you replace the stadard air box to a sports filter you will need to change the jets 10-15% bigger ( 100-102 etc) if you decide to do the jets make sure you get the correct "mm" thread usually 6mm on a smaller carb , but if your saying it doesnt run so good as in spluttering etc upjetting will be needed (10-15%) bigger jet with the standard airbox , when changing jet size start big and work down till the correct one is found , hope this is assists you [Y]