a backfire is caused by incorrect timing or not enough back pressure in the exhaust pipe
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
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.
motorcycle
It could have to do with the fuel mix or your exhaust might not have enough back pressure, i.e. too short, or not enough muffling.
Yes
Motorcycles can stop faster than a car
All vehicles and bicycles must stop at a stop sign, including motorcycles.
Try the link below for an answer. It is for a different bike, but it is a possible solution. http://faq.f650.com/FAQs/BackfiringFAQ.htm
Stop bike and get in car
gas