RK Muffler install

[gibvel]

Okay. Yesterday I tried to install the RK mufflers I got. These are 07s if I remember correctly so they do have a cat. I don't know if that makes any difference on installation.

 

I got a pair of the 31-9920 Chrome clamps. I've spread them out as large as I can make them with a screw driver. I go to put the muffler on and I can only get it on so far. There's about 1/4" of the mating pipe showing still. I've tried using a wood block and a hammer but I don't want to damage any of the upstream exhaust by pounding too hard. I'm thinking of the "Y" weld... don't want to crack that in any way.

 

I used a little anti-seize as someone recommended. The end of the muffler seems to be spreading a bit as I push it on. I'm assuming this is normal. I'm also assuming that the clamp is supposed to go on up to the heat shield and none of the existing exhaust pipe is supposed to show.

 

Let me know if you've experienced a similar situation and what worked for you.

[Hummingbird]

I put them on my 2007 Venture and I remember having to help them a little. Did you clean the receiving end on your exhaust ? There's not a lot of free play and just a little rust/build up can really hinder the sliding.

If the RK's have an indentation from a previous clamp, that could be part of, if not all of your problem.

[Hummingbird]

I just re-read your post -

The catalytic converter may require some jetting work to you Venture. I know it will have SOME effect, I just don't know what

[gibvel]

Yeah, I was wondering about cleaning it the receiving end of the exhaust. I was going to put something about that in my original post but forgot to. That was something I was going to try doing with the next go at it. Thanks for that tip!

 

As far as the Cat causing problems, I guess we don't know for sure because nobody has, as far as I know, tried this type of muffler on their Venture. Do you know this for sure or are you just speculating? I thought about the possibility but decided to go ahead and see what they were like and if they did cause problems.

 

The insides are definitely different. I'll try to describe it best as I can. The one with what I believe is the Cat in it is straight through to the bottom where you see a round disk at the bottom with a cross shape on it (almost looks like a screw on cap). The sides have a steel mesh material all the way down. looking at the output side there is a tube that goes up, maybe 4 to 6 inches into the pipe. at the top it appears as though the tube was crimped in from 4 directions to a center point making a puckered "cross" where they meet at the center The sides of this tube have 1/8" or so holes all the way around and up to the crimp. May be able to get a photo of that but the inside from the input is a no go.

 

The other pipe has nothing to drill out at the receiving end. It goes straight down and there is a flap that juts out of the side of the pipe about 10 or so inches down. The opening faces down toward the output end. If you look at the output end you'll see a similar flap on the opposite side facing toward the receiver end. I assume that this has the flow double back into a second chamber and exhaust out the output end from that chamber.

 

Wish I could get photos of the insides of these buggers. I may be able to get shots of the output sides.

 

I would think that the flow has to be the same between the two as I'm sure the flow and back pressure would need to be the same for both cylinders of a Harley.

 

If all else fails I run to the Local Harley place and see if they have any non-cat mufflers hanging around that they don't want.

[Freebird]

I think you may not get them on any further. It seems that when I tried the RKs on my bike, there was a weld or something that created a bead inside the muffler that prevented it from going on any further. I'm not sure if they are all that way but I know that some are.

[BradT]

Careful how far you beat them on as they do have to come off as well. If you have a wide chisel it make it easier to spread the clamps further than a screwdriver.

 

Small wire wheel on a drill will clean up the recieving end and make things easier. Also double check what Don mentioned as I have seen this as well.

 

Brad

[gibvel]

Thanks Brad and Don. These are things I'll check into. I was able to pull the muffler off again just by wiggling. The clamp I had to spread with a screwdriver and twist off. So they both come off again with a little coaxing.

 

I may just have such a chisel and I'll check for the weld, as well. I'll probably just scotch-brite the end. Have a dremel with a wire wheel but I think that's a bit small.

[SilvrT]

I use emery paper to clean the exhaust pipe coming off the Y. It's easy cause you just wrap it around and hold the two ends with your hands and pull back and forth.

 

My RK's slipped right on all the way and there's no "pipe" showing between the clamp and the heat shield.

 

I've read that some folks have had to take their mufflers to a shop and have the ends expanded a bit to get them on. Might want to try that.

[OutKast]

I put 07 RK's on mine. They were left stock with NO drilling. Seems to run great without any jetting. Just as fast as any other 2nd gen.

 

They will leave some "raw" pipe exposed at the front, but will work OK. The stock mufflers go up on there a really long way. If your new backets are made according to the drawings in the tech section line up with all the bolt holes, that is as far as the muffler will go on.

 

That is why if you search the threads, there are many references to a wider clamp they get at the harley dealers. They leave the clamp hang over the front of the mufflers just enough to cover the raw pipe so all you see is chrome.

[gibvel]

Thanks for all the replies!!

 

Squidley even called and we talked about it for awhile.

 

I may have to run them over to a muffler shop and see if they can expand the tips some as He and SilvrT suggested.

[gibvel]

Think I figured out why the muffler wasn't going on any farther. There's a "step" inside the muffler that is stopping it from going all the way on. The other one, that I wasn't trying, has no such step.

 

This step, when measured with the collar installed, is 2.3" back from the end of the collar. May look into having this ground off, if possible.

 

Sorry the photos are so blurry. It's hard to get a shot of it.