This is a picture of the catalytic converter on the intake end of one of my mufflers from a 2010 FXD. Though I know the principles behind how they work, I'm amazed at the degree of restriction the converter places in the muffler....the orifice openings are about 1/64" (or less) of an inch each...like a rolled up piece of superfine corrugated metal cardboard. The stock mufflers are much heavier than the V&H Straightshots I put on yesterday, and the bike now sounds like a Harley. Sorry for the poor quality of the picture, but I thought a few forum members might find this interesting.

 

when i get my ultra the first thing I'm doing is getting rid of those damn pipes

 

krusty,
What do you figure will happen with age?
Will those little holes plug up?

 

Man they look focked.

 

Thanks for posting this! I just got some Rush 2" mufflers in, ready to replace the stock mufflers. I probably would have wondered what that was.

 

Well that is how the inside of cat's on a car or truck look. Yes they can get plugged up over time and even melt and make an issue. The stock mufflers on my 08 Z1000 has cat's in them like that, but they are off the bike now. I still have a small cat on that bike in the Y-pipe, but it not to bad and helps with back pressure since I have very high flowing pipes. The EPA is on all types of vehicle now and will stop at nothing till out air is clean LOL! Well enjoy the new pipes.

 

Yes, they will plug over a long period of time.

I recently replaced the original catalytic on my '86 Corvette with a high-flow unit. Out of curiosity I cut open part of the old cat. About half of the little holes were plugged. I was amazed that the thing flowed exhaust at all.

 

I can't see how they wouldn't (which is confirmed by others' experience in this thread). I'd be even more concerned about the cats in HD's touring bikes because they're in the headers (the Dyna's stock mufflers with cats are quite large in diameter), and those header cats could only have 1/2 to 1/3 the available surface area exposed to plugging, and the same displacement (so the exhaust volumes would be similar).

I can see why automobile cats are getting stolen off vehicles (and of course why they're so expensive to replace)....there's a lot of metal in there (wikipedia says it's platinium and iridium)....these things are extremely heavy compared to any bike muffler I've ever handled.

 

Ya got it easy, baggers will have the cats in the headpipe, all you got to do is dump the mufflers! That should cool it down some and give you a little low end grunt, plus got your sound back! EPA bikes don't ya just love em!

 

Right! they will be in the headpipe and not the mufflers on the baggers!

When it was just Cali and CVO bikes it was no big thang! Now from 2010 on they all got em! I am predicting the EPA will go after our aftermarket people as we are all of the same accord "the cats gotta go"! You get the sound back, a little of the power back and cool em down a little, the cats gotta go!

Get em while you can!