Jump to content

Recommended Posts

I know this has been discussed here before,but I picked up a new set of rk mufflers that came off of an 09 roadking. I asked the service guy if they had the cats in one or both of them. He didn't know what I was talking about, he said there is no cats in the mufflers from factory, if there was it would calif. only. I did look down through them and there is a difference between the two. So tonight I removed the stockers and just slid them on to hear them, I likely!! Anyhow with one being different than the other would exhaust flow be affected from one side to the other? One a v-twin I guess it would have the same effect as a v4 with both muffs being different. I don't want to modify these mufflers if I don't have to to balance out both sides as flow goes. At idle it does seem as though the left side is a little louder and has some more exhaust flow than the right. I'm waiting for the mounting brackets and clamps to show up to complete the install. Can anyone else tell me if the installed the mufflers with different internals,and if so did you notice any differnce other than sound? Thanks.....:confused24:

Link to comment
Share on other sites

Just because it has a CAt .. does not mean it would restrict flow. A cat when clean wil flow just as good as the rest of the exhaust.

 

Its my understanding that all of the new HD have a cat in one muffler... not sure which side tho. You can easily punch out the cat.

Link to comment
Share on other sites

I have the older RK`s on mine, but I would think that the back presure needs to be the same between the 2 mufflers.., I am sure some one with more knowlege will chime in on this..

 

 

K

I agree with Kbay.

I put Roadhouse exhaust on my bike (sounds like a corvett on steroids:680:) and did the AIS bypass and also had carbs synced after install. I am sure someone will help you out.

Edited by FuzzyRSTD
spelling problem
Link to comment
Share on other sites

Thanks, for the replies. I'm a self employed auto mechanic,and I know what a cat. convertor looks like on a car ,but not sure about a bike exhaust. I looked down through it and it doesn't appear to have any type of honeycomb blockage only a half moon looking baffle at different stages through the muffler. Since both mufflers are some what different inside I'm sure the flow would be different from side to side. These were new take off that didn't even have any exhaust blowed through them until tonight on the venture. I did see some other posts about the stock hd muffs.being as quiet as the venture stock muffs. I can tell you these are not. At idle they have a pronounced low deep rumble an do bark nice when the throttle is opened up. Maybe I'm getting older,but I think they sound pretty good stock. I guess if they were installed on a harley they would work alright with maybe different exhaust pulses being a v twin vs. a v4, just not sure...

Link to comment
Share on other sites

Well I did go through the 2nd gen tech section and on page 65 according to others when looking down through the muffs.there should be a yellow looking brick inside and that is the cat.These muffs. are from an 09 and do not have the cat. in them. So I guess not all later mufflers have the cats. Maybe by certain applications, don't know. I did look at both ends and the one has like offset plugs and the other looks a different with no offset plugs.I guess when the rest of my parts get here I will finish the job and road test.:fingers-crossed-emo

Link to comment
Share on other sites

Look in the front of the right muffler. There will be a cat in there. Not a problem to drill out, just get a long, (aircraft drill bit) 12", approx, say 1/4" drill bit and drill a series of holes around the OD of the cat, then from the back, get a steel rod or pipe and punch it out, not a big deal, then drill out the baffles with a,(i think) 1 1/8" hole saw, Ya gotta do this part first.

 

You will love it.

Steve

Link to comment
Share on other sites

I just picked up a set of mufflers for an Ultra Classic. Have the same thing you have. One muffler is almost empty with just a small baffle extending inward from the outlet side of the muffler 3-4". The other muffler has a long multiple offset baffle that goes all the way through and you can't see light through it.

 

I have been examining the muffler with the long baffle to see if there is a way to get it all out. The flow will definitely be different between the two from the looks if you leave them as is. The Ultra Classic ( and RK) has a balance tube/collector between the head pipes up stream of the mufflers.I think its kind of a 2 into 1 into 2 system.

 

You definitely don't want unbalanced mufflers on the yamaha. I paid $20 for mine on craigslist so I may carve into them for fun, or I may keep looking for a non cat set.

 

Question for those with the non cat early type mufflers. Do they look identical inside Left and right?

 

Thanks,

 

ddog

Link to comment
Share on other sites

I never thoght about that balance tube your talking about, that may equalize the exhaust. Not sure if the roadking bikes have this tube. A friend of mine just traded his fatboy that did have the balance tube, but his ultra does not. I looked as other's have said about the supposed yellow brick inside the inlet end and mine doesn't have this. Standing at the rear of the bike the left muffler has a wire mesh throughout the muffler at the outside edge and right muffler has this plug like baffle throughout the muffler and at the outlet end there is a plug type block in the center with holes surrounding it. May be the newer mufflers are a different type of cat if there is one, but I can's see no yellow type of brick inside either one. I did slide them on and the left side is somewhat louder and appears to be more flow at idle. As I mentioned in my initial post, not sure if flow will have an effect or not. I don't want to modify these mufflers and make them loud, just a nice low deep sound at idle and while cruising. I may just drill out that rear plug thing to increase flow and I'm sure it will increase some sound, but I don't want to screw up the exhaust flow from one side to the other and create other issues. The service guy at the dealership said there was no cats. in the muffler or mufflers.

Link to comment
Share on other sites

Guest wrench

Yes, the non-cats are identical inside. I just acquired 2 sets, one used, one new, cut the plugs out of the used set first, just in case I screwed them up it wouldn't hurt so much. I just finished putting the new set on tonight and they look and sound awesome, plus I'm rid of the blistered tips on the Bub's. I have an extra used set of drilled, non-cat Ultras if anyone is interested.

 

UPDATE

My old Bub's are sold, and I'm getting ready to put a used set of Ultra's in the classifieds.

Thanks for all the assistance with the swap,,,,SWEET!

Edited by wrench
Link to comment
Share on other sites

NewVenture,

I have a set exactly like what you describe. The left one has a good bit more flow. I have color tuned and synced my carbs and can't quite get the bike to smooth after putting these darn things on. Youa re correct, there are NOT any cats in these mufflers.

I amy try to knock out that plug you were talking about on the right muffler. If the engine doesn't smooth out after that, these things are coming off. I like the sound, just don't like the rough running engine.

Link to comment
Share on other sites

Dave38x, I have my muffler's installed today and using a p type clamp temporarily until my mounting brackets show up. I will most likely drill out the plug on the one muffler today and see if that increases the exhaust flow, then have the carbs. synced. If this has the same issues as your bike has I guess will remove them and put the cash back to buy aftermarket mufflers. Let me your progress if you get it dialed in.

Link to comment
Share on other sites

Well, I just got back from about a 10 mile roadtest with the hd mufflers. At idle they sound nice, a mellow tone, but while cruising and accelerating the are not to much louder than stock mufflers,as a matter of fact I did the stage one mod on the stock venture mufflers and they had a lower deeper tone at idle and during cruise. Not sure what to do now, either drill them out or leave them on until I get the cash put back for aftermarket mufflers. The hd's are stock now and cost wise it would be cheaper to modify these. I didn't notice any difference on accelerating. Still has a backfire on the right side and now after the hd installs, I have a very slight backfire on the left side as well. I did a complete plug change as the bike has near 10 k on it. Will get the carbs. synced soon as I hoped the takes care of the backfire/afterfire which I absolutley hate, very annoying and embarrasing. Well that's it for my update for now. Ride safe.....:)

Link to comment
Share on other sites

Well, I just got back from about a 10 mile roadtest with the hd mufflers. At idle they sound nice, a mellow tone, but while cruising and accelerating the are not to much louder than stock mufflers,as a matter of fact I did the stage one mod on the stock venture mufflers and they had a lower deeper tone at idle and during cruise. Not sure what to do now, either drill them out or leave them on until I get the cash put back for aftermarket mufflers. The hd's are stock now and cost wise it would be cheaper to modify these. I didn't notice any difference on accelerating. Still has a backfire on the right side and now after the hd installs, I have a very slight backfire on the left side as well. I did a complete plug change as the bike has near 10 k on it. Will get the carbs. synced soon as I hoped the takes care of the backfire/afterfire which I absolutley hate, very annoying and embarrasing. Well that's it for my update for now. Ride safe.....:)

 

I have the HD pipes on my 06 Midnight and prefer their sound over stock.. But it's when it gets cool out that you'll really appreciate the sound.. I love the de-acceleration sound they make.. By no means a "barking" pipes like the Larosa's I have but on mine, these HD's sound much nicer than the stock ones..

 

I'm leaving tomorrow for PA to see a friend.. Maybe the heat and humidity down there causes a softer sound?

Link to comment
Share on other sites

Seaking, Quite possible about the heat and humidity. Wife and I are going with others tomorrow to York Pa. for the save the plant ride. Local HD. plant may be shutting down and they are having a ride tomorrow and then on Monday another ride from York to Milwalkee with their petition. Other's we are going with all have HD's. and we'll be on our venture, may we'll get the mufflers burned in some and they will somewhat be more pronounced. I can't really notice any bark during accel. May have to modify some. As I said earlier the stock venture muffs. with just the rear cone removed and some holes drilled in the rear baffle were louder. With the stock HD'S on I now can hear the whine again, oh what to do...I would hope all bikes are allowed on this ride not just HD'S, if so we may have rocks throwed at us, ha,ha. Seriously though I hate to see any U.S. industry go down and out...:doh:

Link to comment
Share on other sites

Well I had a fellow venture rider help me sync. my carbs.last night and what a difference. I bought this bike last year and with the help of this site I'm more happy now with the bike than before. The road king mufflers are starting to come around now,a little more pronounced,but not loud. As in my previous post I had some doubts on the muffler switch, but I made the right call. The loud afterfire/backfire is now gone only a nice low rumble on decel, not the embarassing popping. The bike has better acceleration when rolling on the throttle and no slight flat spots throughout the riding rpm's, also idle is smoother. I can 't say enough about the help that fellow venture riders here have helped me with my bike. I purchased the hd mounting plates here from another member and the quality is great. Powercoating is nise and they fit right on without any issues. I can say I practially had a smile on my face the whole 30 or miles home.:big-grin-emoticon:

Link to comment
Share on other sites

  • 2 weeks later...
I purchased the hd mounting plates here from another member and the quality is great. Powercoating is nise and they fit right on without any issues. I can say I practially had a smile on my face the whole 30 or miles home.:big-grin-emoticon:

Where did you get the HD mounting plates? Thanks!

Link to comment
Share on other sites

I've had my RK's on for a few month's now and they had all the baffles so, a couple days ago, I drilled all 3 of them out. Well, does she ever BARK now when I crank it on! Under normal riding, they're not that much louder and the funny thing is, before I drilled them, the sound seemed to come more from under me than behind the bike...now, the sound seems more behind the bike. I LOVE IT! If you got RK's with the baffles and want a bit more rumble and some great BARK, drill out those baffles!

Link to comment
Share on other sites

Did the dirty deed today and drilled out the baffles. At first I was a little disappointed because it was not much louder or deeper idling in the garage. But is like SilvrT says, it comes alive when you get on it. I really like it. It is not much louder than stock RK at highway but you can definitely hear it when you twist the throttle. My GW riding buddy was behind me today and he could hear me everytime I opened it up, but otherwise not.

 

Just curious SilvrT, you mentioned drilling all 3 of the baffles out...where are they? I found two in each muffler and had to drill from front and rear on each one to get them out. Or did you have one muffler with only 1 and 2 in the other??

Link to comment
Share on other sites

Did the dirty deed today and drilled out the baffles. At first I was a little disappointed because it was not much louder or deeper idling in the garage. But is like SilvrT says, it comes alive when you get on it. I really like it. It is not much louder than stock RK at highway but you can definitely hear it when you twist the throttle. My GW riding buddy was behind me today and he could hear me everytime I opened it up, but otherwise not.

 

Just curious SilvrT, you mentioned drilling all 3 of the baffles out...where are they? I found two in each muffler and had to drill from front and rear on each one to get them out. Or did you have one muffler with only 1 and 2 in the other??

 

Far Out! ...

 

glad you're not disappointed coz I sure wasn't going to accept any blame!!

:sign20: :sign just kidding:

 

In mine there were 3 baffles in each muffler...one in the middle closer to the inlet end... one about 6" in from the inlet end and the 3rd about 6" in from the outlet end.

 

Are you sure you got them all? Could you see daylight from one end to the other after you drilled them out?

 

Have you noticed if the sound seems to be coming moreso from the back of the bike versus below you or what?

Link to comment
Share on other sites

Yes there were only 2 baffles in each. I looked straight through end to end so there are no more. :detective:

 

The low rumble at cruising speed seems to come from down below as before, but when you get on it, the sound comes from behind. Weird huh? Weird or not it sounds good...lucky for you SilvrT cause I was definitely gonna blame you!:stickpoke: Gotta a beer for ya next time we meet OK? Thanks for the help.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...