Its not a flathead its an OHV setup. Look in the 3rd picture and you see the camshaft gear meshing with the cranshaft gear. You can see the
There does not seem to be a valve issue either no marks on the piston and it looks like everything was fine in the valvetrain.
Its a pushrod setup if you look close you can see it.
It has a splasher and I was not running it any different than the factory setup.
I did buy this kart used (1 year old kart) and I cannot be certain about the history of the engine.
Another full engine costs $1K.
I am looking for a short block since the externals are all still good.