50cc Keeway stutters then stalls By mpndb (Read 295 times)

[mpndb]

Please help I bought a Keeway 50cc RX8 a few months ago and found that there was no air filter in the stock air box so I ordered a new performance air filter for it. I put it on and retuned the air and fuel ratio so that it idled correctly. It will idle and rev fine when it is on the stand but as soon as I go over 2O kph it starts to stutter and if I don't feather the throttle it stalls out. I thank its not getting enough fuel for the amount of air. Any suggestions.

[trashtruck12172]

might have to go with another main jet. i think the new air filter allows too much air and your running lean. a plug chop should verify this.