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C14 Muffler - Cat removal

FYI, it is a absolute waste of time removing the cats for more noise as it does very little, if anything, in that department. But, remove the cat, the baffle behind it, and them drill the rear like Todd did and it is freaking awesome!! I highly recommend sending your mufflers to Todd for this, it is worth it if you want what I call the perfect sound.

Clayton,

You're going to have to "beat me on the head" with this one...

HOW did you get the catalyst out of the stock muffler?
 
Ok, that makes sense. Do you often switch back and forth mufflers? How to... take a cut off wheel on a hand grinder and cut the front of the muffler off at the factory weld, then take a 4 or 5 inch lag bolt and thread it in to the center of the cat, use a slide hammer and drive it out and weld the front of the muffler back on. make sure you put timing marks on the two pieces so you have them clocked just right when welding them back together. Since you don't care about sound you can leave the front baffle in.
 
Ok, that makes sense. Do you often switch back and forth mufflers? How to... take a cut off wheel on a hand grinder and cut the front of the muffler off at the factory weld, then take a 4 or 5 inch lag bolt and thread it in to the center of the cat, use a slide hammer and drive it out and weld the front of the muffler back on. make sure you put timing marks on the two pieces so you have them clocked just right when welding them back together. Since you don't care about sound you can leave the front baffle in.

Thanks. That helps a lot!

I have had the stock mufflers on for a while and liked them, but then got a new rear tire and put the Mistrals back on. I think the stock mufflers are going to stay on and the Mistrals will be go up for sale.
 
How to... take a cut off wheel on a hand grinder and cut the front of the muffler off at the factory weld, then take a 4 or 5 inch lag bolt and thread it in to the center of the cat, use a slide hammer and drive it out and weld the front of the muffler back on.
You also have to drill out the tack welds on the back end of the cat plate.
 
FYI, it is a absolute waste of time removing the cats for more noise as it does very little, if anything, in that department. But, remove the cat, the baffle behind it, and them drill the rear like Todd did and it is freaking awesome!! I highly recommend sending your mufflers to Todd for this, it is worth it if you want what I call the perfect sound.

Hi Clayton,

I'm wondering with your experience having the modified (gutted) stock mufflers installed did you feel a need to do any fuel modifications because of the change? I know Todd feels a fuel modification is in order for any changes (including stock) in the mufflers but I would like your opinion if I could hold off for now on the fuel mods and the bike still run reasonably well.

Thanks,

Dave
 
Sorry Perk, I had already done Todd's fuel mods prior to gutting the mufflers. But.... of all the mods I have done to the bike the fuel mods were the single best investment as far a the bike running better. I highly recommend it before any exhaust mods. I know it's a lot of money but it's worth it. But know this, the fuel mileage sucks balls at anything over 70mph now and what's worse is my running buddy always runs 85 down the interstate. I might get 30 mpg at that speed.
 
Sorry Perk, I had already done Todd's fuel mods prior to gutting the mufflers. But.... of all the mods I have done to the bike the fuel mods were the single best investment as far a the bike running better. I highly recommend it before any exhaust mods. I know it's a lot of money but it's worth it. But know this, the fuel mileage sucks balls at anything over 70mph now and what's worse is my running buddy always runs 85 down the interstate. I might get 30 mpg at that speed.

Thanks for getting back with me and your brutal honesty on the mpg. Please tell me that was with 2 up riding since that is probably 85% of what I do.

I guess now this leads to another question. What exactly were the fuel mods that were done on your bike?

Thanks,

Dave
 
But know this, the fuel mileage sucks balls at anything over 70mph now and what's worse is my running buddy always runs 85 down the interstate. I might get 30 mpg at that speed.
While these are certainly thirsty motors, and worse when the air temps are cooler, pull and send me the PC-V map, and I'll make some tweaks.
 
Perk, my fueling mods are Todd's full shebang minus exhaust. And 2 up doesn't seem to affect my mileage nearly as much as speed does.

Thanks Todd, will do as soon as I get her back from Mi.
 
I recently had Todd perform the cat removal on my Custom.

I have to say I'm totally pleased. There is a little more rumble at idle and a slight higher tone was added at freeway cruise. I was not looking for loud. This is perfect to my ears. Plus, she runs a little cooler.

I already have the fuel injection system installed and Todd even gave that a second look which is now even cleaner running than before.

I'm totally satisfied. Now I might take a look at the rear suspension adjustment. Or maybe slow down! ;-)
 
anyone just drilled the back baffle, i.e. left internal baffle and Cat in place. Would be interested to hear what that sounds like
 
It actually made quite a difference at idle, the exhaust pulses are a lot more distinguishable. Off idle tho still whisper quiet. The next logical thing to do is to insert a long drill into the end and drill a hole. Starting small of course and increasing as you want more noise. I'm hesitant though, it will be irreversible and my luck I would develop a whistle and sound like tweety bird flying down the highway.
Did you ever get around to drilling out the end baffle? And if so what size hole did you end up with?
 
Pretty sure I went with a 1" bit. I took a piece of 1" CRS and turned one end down to fit a 1/2" drill and tacked the other end to a drill bit. Worked well.
 
Hello , what would it cost to have this done on my Eldorado ? I know I would have to get them to you and me living in Canada could end up costing a pile of Dough . Please let me . Thanks
Thanks Brad, but as it says, email me to that address. Publishing pricing here always bites me as people search this years later and ask why it's more expensive, often 5+ years later.
 
I recently had Todd perform the cat removal on my Custom.

I have to say I'm totally pleased. There is a little more rumble at idle and a slight higher tone was added at freeway cruise. I was not looking for loud. This is perfect to my ears. Plus, she runs a little cooler.

I already have the fuel injection system installed and Todd even gave that a second look which is now even cleaner running than before.

I'm totally satisfied. Now I might take a look at the rear suspension adjustment. Or maybe slow down! ;-)

Hello , I think your bike sounds awesome , if it is the one I have heard on Youtube ? I think I will be sending mine in as well .
 
OK, so I modified a set completely, including drilling out the rest of the mufflers. Video below.
85 db at idle, 95 db at 3k RPM steady, and a loud 110 db at quick jab of the throttle at close range. We also did a set of LaFranconi Competizione versions, with the same db results (db-killers out) but with a a slight deeper sound. Internally they are identical internally to stock (including cat-cons), outside of the removable db-killer and end propeller design element.
We can offer this service with exchange of your mufflers. Contact me direct for more info and pricing; Info at GuzziTech.com


Hello All I'm new here as I just got myself a C14c. Fantastic forum, great way to share ideas and get info.. I just bought the computer flash setup ( can't wait till it comes ) from GTM. Meanwhile I want to mod my stock mufflers per video. I've read everything about it on this thread, but would like a little more descriptive detail, pics, ect, back plate mod maybe. Can more be done for a deeper tone? All comments would be very appreciated. Cheers!
 
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