adjusted

I have about two second delay between when engine revs and xr50 picks up and goes when I throttle up . also jerks when throttling down. It's an 03 xr50 stock motor. Just replaced clutch plates and put bbr springs. Clutch is adjusted properly and broken in. Carb is adjusted properly. Anyone...

Just wanted to find out if anyone would know a possible solution to a problem im having, if I roll off the the throttle not even that quickly sometimes the bike seems to backfire a lot. Also im getting quite a bit of oil and smoke coming out of the exhaust. I have adjusted the screw on the...