I have just fitted a vance and hines big radius 2 into 2 system to my 2017 Fatboy and have a strange sound in the low to mid rev range under load that I cant track down it sounds almost like a sewing machine. I've been back over the install on pipes everything is tight. As yet I have not had a tune done which is next but just thought I'd see if anyone might have done ideas as I'm not sure getting the tune done will solve this.

 

Maybe one of the baffles are rattling, check when hot with a large screwdriver.
You can also check if the sound is appearing without the chrome covers, just with the bear pipes.

 

So an update on my noise its apparently a valve guide issue and needs a new head gonna take a month or two as Harley dont have the parts really disappointing for my first Harley bike is only 12 months old with 3500kms I bought it and I e done less than 70km on it

 

Deleted.... I just noticed you're not in the US.

Good luck with your issue.

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