Pocket Bike Exhaust

I let my friends borrow my 2-stroke 49cc CAG. pocket bike a little and he never bothered to check or tighten bolts and screws to be up and caused my exhaust up to crack off, also the exhaust hole where it screws into the engine a missing piece. suggestions on how to solve this problem without having to buy a new exhaust system and engine?

If the frame is steel, it can be welded, but be sure to use a MIG welder. It will be much stronger and hold up much longer. you may be able to make some sort of mounting plate for the exhaust, or you may be able to re-tap the hole and use an oversized screw or bolt to attach the hose.