Sound from the muffler should be directed BACK and AWAY from the rider... something isn't right from the sounds of things
I'm wondering if the new muffler has a 'complete and proper seal' around the 'muffler / mid-pipe section'... it could explain why the noise is louder for the rider and not those behind you, might be letting exhaust/sound waves out and back towards the rider if the muffler has any kind of gap around it and the exhaust pipe
?? Just a thought from someone a thousand + miles away, maybe start the bike and use your hand around the muffler and other exhaust parts to check for any air leaks ??
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