Please help, My Son has a Beta Rev 50! the poor little engine struggles at the bottom end picking itself up! Can anyone advise on tuning etc? Or is it a characteristic of the engine?

Spark plug ?

Spark plug gap?

Mixture screw setting?

Oil mixture?

Any other advise?

Thanks Chris

A beta 50 should make reasonable power but any wear on any 50 has a disproportionately negative effect on performance. I would check the exhaust and exhaust port are not coke up. Take the barrel off and check for bore rings and piston wear.

the ignition system can be weak and this reduces bottom end power. An iridium spark plug will help. Other than that make sure the air filter is clean and the carburation and timing are spot on.

Thats great advice thanks! Sounds like I need to give it a strip down and freshen it up a bit!