Did you start in the middle, to the side or ? What happens when you have much of it out and there's not a solid surface to start the bit on?

 

I pretty much went in concentric with the straight outlet pipe first, then moved over and drilled another path more-or-less in line with the perpendicular outlet. After that, I used the piece of 3/4" conduit with a three pound hammer to shear the rest of it out, finally scraping along the insides of the can. The last step was to put the roughly 45 degree angle on the last 2 inches of the conduit to reach the otherwise inaccessible part that is hidden by the perpendicular outlet.

All this would make sense if you were looking at one; probably doesn't otherwise.

In any event, it was an easy though somewhat time consuming exercise and very much worth the trouble in my estimation.

I'm an old fat man and removing and replacing the pipe while squatting was a pretty daunting chore. Wouldn't have been if I had a lift, but, alas, I don't.

 

I did go ahead and remove the baffles from the extra set of mufflers I had and installed them; I didn't like the sound (too harsh) and put the originals back on. I think I'll be happy with the combination of the de-catted pipe and the original mufflers at least for a while. I think I'd rather spend my next "mad money" on a back rest and maybe a luggage rack before I'll worry about mufflers.

For what it's worth, removing the baffles is extremely easy; I used a 1 1/2" hole saw which just fits inside the first inch or so of the baffle and cuts the rest of it off where it steps to a smaller diameter. The result is a muffler that still looks stock even if you look pretty closely but is straight through from inlet to outlet with just some packing around the outside.

 

If I understand correctly, you only drilled two holes and used the conduit to bash through the rest?

 

That's pretty much it. You can drill the first two holes, but after that, as you had surmised in your first question, there really isn't anything to start a spade bit on. By using the hollow piece of conduit, it is more of a chiseling operation than bashing, but the material is removed in chunks.

I held the pipe vertically in an old "WorkMate" and dumped the material out periodically. The whole process took about thirty to forty minutes. I went pretty slowly, figuring it out as I went. I could probably do another one in half that.

There are other threads wherein people cut the chamber open, cleaned out the cat, and welded it back together. I read all I could find before I did mine. I reasoned that I could try the drilling/bashing method first and if I wasn't satisfied I could still cut it open and finish it. However, it is my belief after having done one that this is the superior method.

 

it is a better way to remove it. i used an angled pry bar to tap any material left over out.

 

Perhaps a stupid question... but can this be done while the head pipes remain on the bike, on a lift? If so, I may decide to tackle it on both the wife's 2010 RK and the 2015 RGS. It was always something in the back of my mind... it's just hard to justify spending time doing this rather than riding ;-). This looks to be the least expensive route though while still being effective after seeing these pics, especially when two bikes are involved.

 

I've tried the window method and it does work but I will say that you need to be able to weld it yourself or have a friend that will do it for free - otherwise you might as well buy one off ebay as the cost won't be that much more. Also, it needs to be welded in a jib or on the bike........had mine done (welded) on the bench and the heat must have shifted it as the RH side outlet move slightly inboard making lining everything up with sufficient axle clearance a bit of a PITA.

Honestly, having done the window thing and knowing what a pain it was to grind everything clean inside, I really didn't think you could drill and get it as clean. Photos prove me wrong though. I had planed to get one of ebay (which is less than dealer cost on the cheapest aftermarket header) but now I guess I will get a drill bit and give it a go. Question is, on or off the bike - I'm thinking on will be easier once its up on the lift .


PS - for those without a camera to check progress.........go on ebay and search "scope camera" There's loads of USB versions with lights for next to nothing - as little as $12

 

I've been debating this topic for a week. One buddy with plasma cutter and another claims he can weld. So in the end I got on line, found a guy who does it right including grinding the weld down..... God, I'm so lazy.

$150. Shipped this morning. Could have bought it $125. shipped from same fellow. No biggie. It's on its way.

My stock head pipe is probably worth $75. Or whatever. So we'll see how it goes.....

 

Either way will work; your choice. I prefer the drilling/chiseling method because it's faster, easier, and doesn't add a chance of rust or warping. Plus it is invisible from the outside. But the window method will get you to the same place, and one thing I'm pretty sure of is that you'll be happy with the results either way. I don't really think it's much if any louder, but the sound is deeper and much more pleasing to my ear. The real treat is a noticeable increase in torque.

I really would recommend taking the pipe off the bike to do it though, especially if you have a lift. It is an easy job and that allows you to hold the pipe vertically and look into it well while you work. It also allows you to dump all the debris out as you go. I think I mentioned I used a Black & Decker "Workmate" to hold mine; worked great.

It's good to see all the interest in this; glad I bumped the thread up. The OP did a great job of taking pictures.

I went to my dealer and got a new takeoff pipe to work on so I wouldn't have to modify mine. I'd recommend that if you can; that way you can experiment all you like with getting all the cat out before you have to park your bike.

I say to anyone considering it---go for it. Mine took about 2 hours start to finish, including removing and reinstalling heat shields, right footboard, right saddlebag, and right muffler. Take the single screw out of the clamp that holds the crossover pipe to its bracket (just in front of the rear tire) and the left muffler and crossover pipe pull out of the header very easily. Once you've done all that, you only have to loosen the one bolt that holds the cat to its bracket and remove the four nuts that secure the pipes to the cylinder head and it'll all come right off. At that point you'll need to unscrew the two oxygen sensors...be sure to note which one went in which hole; it matters. Reassembly is the reverse, though I'll admit it's a little clumsy.

I think I could do another one in an hour and a half start to finish, especially if I had access to a lift.