I don't know this bike and no idea what Carb it's using. I'm guessing it's some sort of small Chinese CV carb? ... so should be a Fuel Screw (AKA Pilot fuel/air adjustment screw) on there somewhere.
These screws are often hidden under float bowl, possibly recessed, hidden with tin cover blocking access. (easily removed)
To Note: It's not unusual to lose A LOT of power at high altitude. Even with proper jetting and with Fuel Screw leaned out sufficiently, you will still lose A LOT of power. It will get worse as you go higher.
And F.I. system may run cleaner up high, a F.I. bike will lose just as much power as Carb ... all due to lack of Oxygen at higher altitudes.
Adjusting the Fuel Screw will help starting, idle and throttle response off idle, but will NOT increase power. (Sorry!)
|