81 yamaha it175?

Question

hi thanks the engine idled really good before i took it a part.the issue was when i hit the throttle it would bog down wanting to die out.tomorrow i will check my reeds and clean out my jets.

Answer 1

If you did a bore job top end it is probably dragging aluminum piston on the cylinder walls and will need to be torn down again.If the ports were not champhered after a bore job the rings will hang up on the ports causing burs to gouge into the piston skirt.So ,if I am correct you will need the ports champhered,aluminum removed from cylinder with boric acid and a light honeing and the piston will need either replaced or sanded a little.Could also be a bad air s***w adjustment  and/or improperly timed.