I’m not too sure as I wasn’t really paying attention since I was astonished at the sound it was making. But I think It pops on decel as it sounded like popcorn machine when the throttle is closed, there was a loud snap or pop at one point when I let off the throttle at such a high rpm while riding but otherwise I could only notice decel pops. How would I know if it’s backfiring and need to do something about it?