Bogging out with air filter on

[Hyper29er80cc]

I’ve built a few bikes, but this time with the air filter on it Boggs out at about half throttle than wants to die out. First time ever with this problem after about 12-15 builds. I just run it without the air filter, only ride on paved roads. This bike pictured is my daily driver, hyper 29er with a 80cc.
halifax, ns, Canada here.

 

[Greg58]

Welcome to the forum, sorry we missed your post. If it runs better without the air filter you need a smaller jet.

 

[Testname111]

Oil seals? They tricky