Well, that's clearly not true. It may be accurate in some cases like short shots or when people pull baffles, but for example D&D Fat Cats and ThunderHeaders are two of the best performing (documented) pipes you can buy. And both are quite loud...

 

And both of them have decently-sized muffler cans, although different designs. This is the only real way to get pipes to tune broadly. Longer version of what Canuck1 wrote.

The muffler cans (and air intake box) on my Busa are humongous. It breaks my heart when I see one of these bikes with those stupid little pipes exhausting right at the rider's foot. Breaks my ears too!

 

Back to one of my questions, I really want to take out the 2-1 S&S SuperStreet 50 state street legal dB reducer. I know the performance issue, but (1) want to hear sound difference, and (2) I’m bored sitting at home. But the bolts holding the dB reducer have some pin in them which doesn’t allow using Allen key. I think* it’s some security lock so people don’t tinker with the street legal. Anybody advice on this particular pipe, on how to take out dB reducer? On other pipes it’s easy.

 

Do a search. There was another thread on this same subject and they found the special tool needed. It's like a torx security head, but different... Definitely not any variation of an allen key,

Edit: Here: https://www.hdforums.com/forum/2018-...tant-bolt.html

 

I have the S&S slip ons, and the cores had the same bolts I think, I used security Torx (they have a little hole in the middle to go around the pin) and it worked fine

 

I thought I read on the above thread that it wasn't actually a security torx bolt. (I never tried it myself) But if it worked, it worked. They are easier to obtain then the $50 tool I thought they were talking about!!

Nice.

 

Yep, they are like a security-allen but I got a torx in there. I have a sport bike convert buddy who only uses metric, even on his standard stuff lol.

Stock 107 I don't feel any loss in low end without the cores, but she does have a little more Yo-Hooo! on the freeway

 

So glad I found these posts. I just had a 124 kit installed in my ‘17 RGS and am experiencing exactly this problem. 150hp and goes like a missile above 3500 rpm, but below that is quite lame, only pulling mid 130s tq. Yes I have a mid range cam CR470, but it seems the high hp Bassani 2 into 1 is too free flowing, check the size of the collector. The supplier of the 124 kit is sending me a S&S db reducer, so I’ll be keen to see if it lifts the torque curve below 3500 like the dyno chart comparison above.

 

I'm keen to see if a S&S dB reducer fits a Bassani muffler.

 

I’m told it does. Will soon find out.