I fitted the  Smartpartz Quiet Baffles for Big Radius (SPZVHBR) on my bike and I am very supprised what a difference they made, the bike is much quieter when riding but still has a nice deep sound when reved , the down low power has improved dramatically especially 3rd and 4th gears.

I am verry pleased with the result as I did not think they would be such an improvement.

 

The bike is a 2012 ,103 fatboy with Fuelpak and K&N filter. . 

I put a set on the Mrs Yamaha 650 which had the V&H Cruzers on it. it quietened it down just nice.....I actually was considering them for Kerker Mean Mothers I was going to get for my Softail in case they were to loud,,,,,,,,,,,but I ended up going a diifferent way,,Screamin Eagle......my ears are old.!!!

Put the same baffles into a big radius 2 into 2 of my 07 FXDL; what I've notice is the added torque.  Before, I had to be at least going 90 kph before I could shift into 6th gear in the flats, lower than that you feel the engine laboring.  Now I can easily cruise in 6th gear at 80 kph in the flats.  And its not only in 6th, from 3rd I'd notice the difference,  Also, the sound it produces when cruising at 80 kph in 6th (when the engine is just a little above rev range from being under rev) that for me is what a harley should sound while cruising.  I installed the baffles a few days before an 8 days, 4T+ km ride last month.  Also, probably improved mileage per tankful.  But probably also still not safe from EPA.

I have a set in case the EPA sniff my arse, and I can tell you that in a set of Big Radius on a 96er, they don't get you under the limit. My bike is still up over the 100db mark with them in.