no video ?, but i rebuilt a top end on a trx400fm years ago, started right up, then had the loudest knocking noise i've ever heard ?!. tore the head back off, seen the problem right off the bat !. some how ...do not know how or where from ???, a screw got sucked through the carb, into the intake, and got settled on top of the piston, and was getting hammered to death !!. so, word from the wise, when doing top end work ?, ALWAYS MAKE SURE ALL SCREWS ARE TIGHT ANY WHERE NEAR THE CARB..AND INSIDE THE CARB !..LOL.