as you know i put a crf70 head, cylinder and carb on my 07 crf50. Now theres no power in 1st and 2nd didnt even try third. The bike goes, then boggs out or revs out way fast. When i let off the throttle, seems like the engine braking takes over and it stops quite quickly. Whats going on with my sht????

Also oil sputtered out of the black box that the air filter hose usually plugs into. The motor started smoking when i tried to do first gear circles. Whats up????