i have a kawasaki vulcan 900. when i release the throttle i hear a popping sound coming from the area behind the air cleaner. it happens mainly when i use a small amount of throttle. when i rev it up it doesn't happen. couuld it be the air switch unit? am i harming the engine by riding it?

 

Not really sure. Check all of your connections and tighten or align as needed. Look for anything abnormal.
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