there is a sprag clutch in the starter system the motor can run backwards for a bit if you turn off with the key switch
or kill on the right handle bar // by using the compression release on the left the engine does not hammer the Sprag
then turn off the key
the Sprag is a very expensive repair and over time you will get longer life out of it
also never back down a hill with the engine off using the clutch to hold you back
as it makes the sprag in to the brake and that is what it does break your pocket book
do not ask how i know ..just look in my empty pocket book
dave
https://en.wikipedia.org/wiki/Sprag_clutchas the motor runs and you turn it off with the key it can come up against the compression stroke...
if it stops or backfires against the piston and then it can run the motor back wards you may hear it as a loud bang
even as loud as a shotgun
and it may start but will probably be spreading broken metal parts threw the engine
if a bike has a compression release i always use it to start the bike as well as stop it
also while we learn ...read this for that fire breathing beast you want to ride
https://en.wikipedia.org/wiki/Slipper_clutch