a backfire is caused by incorrect timing or not enough back pressure in the exhaust pipe
Unburned fuel in the exhaust system causes the backfire from the exhaust pipe.
I think you are hearing pressure pops. Not a backfire.
A motorcycle jerk or backfire can come from the choke not shutting off completely, the fuel jets might be clogged, a gasket or seal may be broken. Valves that are out of adjustment could also be the problem.
to much fuel is going to the engine for it to burn it all
It's lean.
It's lean.
probably a bad spark, itll cause your engine to misfire flooding petrol in without igniting it, when it sparks afterwards it ignites causing a bang and backfire.
Backfire is normally caused by engine out of time, or spark plug wires installed incorrectly.
bad gas
Too much PSI.
Out of time.
Your car is running too rich.