muffler mod

BA · June 05, 2009, 08:26:07 PM

Terry,

I did the mod last night after work and road home, then did the round trip to work today. I like the aggressive sound as you accelerate, not much difference while cruising down the highway, but decelerating I get quite a bit of popping from the exhaust (more so from the left side). It seams a little raspy but not obnoxious, and they are no where near as loud as Chad's V&H pipes.

BA

TLRam1 · June 08, 2009, 12:27:37 AM

Quote from: BA on June 05, 2009, 08:26:07 PM
Terry,

I did the mod last night after work and road home, then did the round trip to work today. I like the aggressive sound as you accelerate, not much difference while cruising down the highway, but decelerating I get quite a bit of popping from the exhaust (more so from the left side). It seams a little raspy but not obnoxious, and they are no where near as loud as Chad's V&H pipes.

BA

Great BA, I like the popping personally, you and Chad can get that out easy though. I also get more from the left side it seems, for one reason.... you hear the popping more now rather than stock because the stock are quiet and you might need to adjust your carbs.

I thought you and Chad did some work on them, a little popping is fine just not your big backfires. You have one of the guys in the know in MI. so you are in good hands.

BA · June 08, 2009, 10:40:28 PM

Yes, popping is more on the left side of the bike. Another guy on the ride had done the original muffler mod and removed the rear baffle, etc., but I really didn't care for it. It just didn't sound right accelerating and quite a bit more popping.

I plan to sync the carbs then use the exhaust gas analyzer at school to set the mixture and run it on the dyno to check how the main jets/shims are. That'll be the best opportunity to get it right.

hootmon · June 09, 2009, 09:21:05 AM

Quote from: knrhodes on May 29, 2009, 09:53:00 AM
Nice - I have already done the two hole - 1/2 (I need to sand it down and paint to make it look pretty) - it louder but l would like it to be even louder - might look into the two larger holes - but curious wouldnt one larger hole be the same?

Who has done one hole, then gone to two holes?
I presently have one and would like to go to two.. I would not mind it being even a bit louder. It would seem at some point it would might actually get quieter with less restriction and more places to escape..
Also back pressure changes.. I added 1 shim, but wonder if I might need to go to two if I add another shim.. Any opinions??

Does anyone know what the baffle looks like inside?? Would it be possible to weld a HSS drill to a rod and send it up the baffle and drill a single hole in the far end?? (assuming it is tapered and welded at the far end..) None of the Tips and tricks photos show the baffle..

Charles S Otwell · June 09, 2009, 09:55:39 AM

Here are pics of the rear plate removed, the rear plate has a resonator which in this pic has been cut off. The actual baffles are farther up in the muffler as you can see in the next two pics, they are welded in.

hootmon · June 09, 2009, 10:53:10 AM

Thanx Charles.. So, do you think it would be possible to drill through the resonator with the method I suggested? (No picture looking into the resonator)
Anybody have an opinion on if that will give the exhaust a tinnier sound?
It should relieve backpressure, No?

Charles S Otwell · June 09, 2009, 04:11:49 PM

In the top pic the middle section is the resonator and all three pieces are already open, You can start by cutting off the short piece in front of the resonator (far right in pic) if that's not loud enough, you can cut the resonator next, each cut it'll get a little louder. If you cut the pieces at a slight angle (so you can realign) the process is reversable with a little welding. The next step would be to enlarge the center hole in the end plate, after that Greg's suggestion to drill holes in the actual baffles with a long bit. Don't know if anyone has tried this yet, maybe someone else can answer that question. I stopped with removing the resonator, to me it sounds better than stock but not as good as Vance and Hines and a whole lot cheaper. It's my wife's bike now and she wants it louder, but rather than drill the baffles (which I consider erreversable) think I'm going to bolt on four Sportster shorty's. I can pick up pull-offs for about $20.00 a piece. Takes a little modifying but not bad.

Capt. Howard · June 09, 2009, 05:57:46 PM

Charles....about the Sportster pull offs....Are you referring to the stock mufflers and what year models?..I want to quieten mine down...It came with drag pipes that really "SUCK"...I want something to modify that has baffles...Thanks in advance......

Charles S Otwell · June 10, 2009, 02:40:06 AM

Not sure what year models are alike. As far as being quieter I'm not sure they would be, even on the 883's each muffler is built to handle 440 cc's so 750cc's divided between four is probably not going to have much if any back pressure. I ran across these pull offs while looking for a muffler mod for a 650 Savage (thumper). The one I bought was straight thru, looked like a chrome glass pack. I will check for ones with baffles , but the one we put on the Savage was good looking but loud, Anyway I'll get more info and pics on the sporty mufflers first chance I get..

Are you interested in trading or selling your Drag pipes and what kind are they, wouldn't mind having a set of the straight style drag pipes , don't much care for the megaphone shaped ones.

Capt. Howard · June 10, 2009, 02:49:27 PM

Charles...Thanks for the info on the muffs....I would not sell the straight pipes to anyone...They would need to be re chromed...I will gladly give them to you when I get something else...I just got me shop built and I'm a small engine repair shop...lawnmowers,weed-eaters,chainsaws..ect..This is the busy time of year so it will probably be winter before I get to mod my bike....But you do have first grab on pipes if you want them...Thanks for your help...I believe I will build 4 into 2 when I make the mod..