Back firing

[Roy]

Why did my xs1-b start popping, backfiring during deceleration? This is a new development.

 

[jpdevol]

Why did my xs1-b start popping, backfiring during deceleration? This is a new development.

That's a classic symptom of too lean carburetion - particularly the pilot circuit. It's unusual for it to show-up in summertime (warmer less dense air) without some preceding mechanical change. There are other causes, but I might open the pilot screws a half turn, just to see if it changes anything.

 

[5twins]

Sounds like you may have developed an intake air leak somewhere.

 

[gggGary]

a throttle cable can easily get in trouble, hooked, bent, just routed oddly, throwing the sync between the sides way out of whack.
snap, crackle, pop.

 

[Raymond]

Why did my xs1-b start popping, backfiring during deceleration? This is a new development.

I've had this happen due to the pilot jet getting gummed up with modern fuel with ethanol content, especially if the bike has sat un-used for a week or two.

 

[Paul Sutton]

Another cause is air leaking into the exhaust pipes. Could be a hole or loose clamps.

 

[JJames]

I've had this happen due to the pilot jet getting gummed up with modern fuel with ethanol content, especially if the bike has sat un-used for a week or two.

Yep, little chunk of something broke loose somewhere.