I want to knock out the baffles in my pipes.

Id like to for people to hear me before they see me if you know what I mean.

Anyone have some good instruction on how to make stock pipes louder?

Much appreciation for a quick and easy tutorial.

I am looking at doing something like this video. :lol:

http://www.youtube.com/watch?v=11k_A_yzyfc

 

Louder is easy, just go to a muffler shop and replace the muffler with nothing.

Less loud than that is tricky. You can buy an aftermarket muffler, or you can do what I was forced to do when the bike I bought came with a straight pipe. Buy a baffle and some fiberglass, and stuff them in the straight pipe. I used washers to restrict the flow a bit also.

You can get aftermarket mufflers that are in the old megaphone style.

 

The easiest way would be to remove the mufflers and drill through from the exit side with a large drill bit. If you look in there with a flashlight, you will see a baffle about 6" in or so. Maybe even drill from both ends.

I have also seen people drill a series of holes in a circle in the plate around the outlet pipe, but without punching through the baffle I never could see how this does any good.

Be careful with the "knocking out the baffle" idea, you may end up distorting the outside of the muffler "can." I have a Seca 550 muffler with the baffle broken loose inside, and the can is all lumpy-bumpy.

 

If your current mufflers look reasonably nice, you may want to keep them.
Go to an auto parts store and buy the correct size pipe "inner" and a chrome slash tip, weld them up (X2)

You could then experiment with removable washers to modify the sound.

 

I guess there is no easy way.

 

on my v-rod, i drilled holes AROUND the baffle on the end cap. its a cheap and easy way to get more sound and not have to get a chip.
that being said, i dont know how it will affect a carb'd bike, as far as jetting is concerned, as fuel injection can accommodate for SMALL changes on its own.

it gave me a FEW decibels over stock, and that is a HUGE improvement on a v-rod, s it sounds like a sewing machine with the stock pipes and baffles.

the best way to do it (as was found in the forums) was to make a pattern (stock pipes on a rod arent round) in paper, find the EXACT center between the baffle and outer pipe, punch 4-8 holes around the plate pattern and drill with UP TO a 3/8" bit.
using 4 holes at 12, 3, 6, and 9 locations produces little difference, 6 is what i used and it sounded ok, i cant comment on 8 holes since i never did it, but once you START drilling holes, youre stuck with that pattern. the nice thing is a competent welder CAN fill them in if you decide you dont like it, but you can never redrill after that.

 

if you want to be heard before you are seen then you need to turn the mufflers forward. not even straight pipes can be heard (in a car with the radio on going down the highway) until the bike is right next to the car.

as for drilling out the muffler, dont do it unless you are ready to rejet. quite often people drill the baffles out and suddenly have a crappy running bike.

 

I like the "turn the pipes forward" idea....... one of you mod guys need to do this for the est of us to see!

 

From the 1981 DOT Hurt Study, page 411.
"The modified exhaust system was typical of many accident-involved
motorcycles, and also typical of many motorcycles observed during exposure data collection. The modified exhaust is overrepresented in these data, but not with high significance."
Proceed at your own risk. The single biggest means of giving yourself a better chance at being noticed is by increasing your frontal size, via a fairing (again, refer to the Hurt study findings). Loud pipes statistically do NOT save lives, they only serve to annoy and are illegal in most areas.

 

I have to admit, it was hard to respond to the original post without flaming a fellow contributor for purposely being obnoxious. That would be a bit hypocritical, though. I myself have worked hard to bring the straight pipes I bought my bike with down to a reasonable sound level. With all honesty, however, mine are likely louder than what Mr. Brock is going for. I could drop the $$$ for attenuation, but apparently it's not worth 3 digits of dollars to me. Plus, how would my dog know when I'm about to be home?

I almost said the same thing about facing the pipes forward, but Mr. Brock didn't say anything about increasing safety with increased sound. Perhaps it's because I live by the beach, with a lot of motorcycle traffic on the weekends, that I perceived his intention as towards people sitting in their homes watching tv, not out on a highway. That's the only place I ever hear motorcycles. I also hear helocopters and fighter jets, but since I've spent a lifetime on military installations, that's nothing new to me.

Mr. Brock, if you do decide to go very loud, I will trade you pipes. I would like very quiet. I ride like a Ninja. Quiet, effective, and without getting myself hurt.

 

I truly value everyones opinion. With that being said, Im still waiting for the answer. LOL.
Welding and Studies will not make my bike louder with ease. :?:

 

I personally would like to see the inside of a Maxim muffler, to see how it is made. If we knew that maybe we could tell you how to (or even if you could) take the insides out without destroying the outside.

That is pretty much what you want to do, right?

I just watched the video, btw. I think the title should be changed, since they never actually remove the baffle. There were a lot of similar videos, have you tried those?

 

I know what's in a Seca muffler and I suspect the design is pretty much the same; there's an inner pipe suspended between two bulkeads with baffles obstructing direct flow to and from said inner pipe.

Pretty much like any old-school car muffler.

The mufflers on my Norton however, are quite interesting: You can look right through them. Inside, the inner pipe flattens on two sides and along those flattened areas are a series of "shark-gills."

They were stock in 1974 and therefore perfectly legal but the bike has a really nice bark.

 

Is the inner pipe offset? I always wondered that in stock motorcycle mufflers, since they are so small I don't really see much chance to have an offset, especially in a megaphone type muffler.

Also, it almost sounds like you would have to break the weld from the bulkhead to the shell to get the baffle out, is that the case?

I bought some baffles online for $15 that look alot like what you are describing for your Norton. I had some washers welded into them to create a constriction/expansion/constriction effect, wrapped them in fiberglass, and stuffed them into my po's straight pipes. Sounded like a 125cc when they were at the end of the pipe, but once I stuck them down further it went from a piccolo to a tuba. Not too bad, and a lot quieter than most, but still not Ninja quiet (the assassin, not the motorcycle), like I would prefer. Very distinctive, that's for sure.

 

The one I saw cut open, I'm pretty sure the inner pipe wasn't offset by much, IIRC.

Right. Which is why I mentioned my one lumpy-bumpy muffler, the innards are broke loose and it distorted the can. (I'm not running that muffler, it got replaced.) Which is also why I recommended drilling through the baffle rather than trying to remove it.

Based on the construction of the Yamaha mufflers I'm familiar with, and my experience with a set of "drilled" Seca mufflers (they went back, I didn't fit them) I don't think drilling holes around the outlet pipe will be effective as long as the innner baffles are intact.

One quick personal note: I spent a lot of time, effort, money and tears getting two stock exhaust systems back onto my 550 Secas. I'm NOT advocating loud exhausts at all; I love the quiet "whoosh" of the 550 at low rpms and the stock exhaust provides a very satisfying HOWL when the tach gets past 6K.

I just don't want to see somebody screw up a perfectly good set of mufflers trying to make them louder when it can be done nearly invisibly, albeit conservatively.

 

Sell off your stock mufflers and pipes and buy some headers made with removable baffles. Let someone that is looking for a nice stock exhaust pay you good money for them and buy what you want. It would be better to work with a set of headers anyway to get the sound you want. Look for a 4 into 1 set up.

 

I've got a set of 650 Max mufflers that have had the rear caps drilled. I'd love to trade for a set that haven't been thusly modified.

 

My pipes are welded to the mufflers.

 

Robert,
What do those sound like?
Do you have a picture of one end?

 

Bill, the carbs are off of the bike at the moment but pictures would not be a problem. I'll try to snap some off this weekend.

 

i was just wondering if they sound different than stock mufflers.

 

I put screamin' eagle slashed exhaust tips on my xj650 and it sounds really mean at idle.

 

They are a little louder but not overly obnoxious. I'm waiting on an airbox for this bike (it had pods) so a sound bite will be a while in coming.