2003 blaster question plese help

[1130all]

i recently rebuilt my blaster and when i put it together it had a knock sound coming from the motor piston is tight in the cylinder and the rod bearings is tight .could the crankshaft bearings cause this .my blaster motor sounds bad compared to my buddys,i would like to make it last.thanks for any help

 

[R&S Polishing]

sounds simple but is their oil in the tranny? the other thing i have seen is the cir clips come loose and allow the wrist pin to slide out? just trying to help