Bonneville America Forums Forums Technical Forums Exhaust Baffle removal

I just bought a set of like new mufflers for a 2003 America on ebay. My plan is to remove the baffles. Looks to me like there are two welds at the rear end to drill out and the rolled edge to grind off. If I do these two things, will the baffles slide right out?

I think that's right but I just drilled a few 1/2" holes around the pipe that bisects the rear-most baffle, removed the pipe, and ground down the remaining plate section until only a 1/4" inch or so was left as a ring around the inside of the muffler. I then used the LONG 1/2" drill bit to drill 4 holes in the next baffle plate up stream. Sound is VERY sweet!

here is how i did:

At the rear of the pipes the insert is welded in place by two welds, you will see where it is on the outside of the pipes, drill those weldings out.

Take the pipes to a machine shop and saw of the pipes to the length that you
want ( i like the stock look so i did only saw off the end that is bent, this has to go or you cant get the insert out.) with the right saw the crome will not be
damaged.

Now you can take the whole insert out and then remove the sounddamping
material on the inside of the pipes.( removing this is what make your pipes
sound sweet!, you can drill out the baffles all you want but if you dont take out
the whole insert and get this out it never will sound right!)

Rebolt the hangers

At this stage you got the pipes that will make you the guy that draws all the
attention at the bikemeet :-) (to loud and screaming out at crusing speed!!)

What i did after that was take the inserts from my Raask aftermarket pipes
and fitted them inside, just slipped them in and used one of the holes i had
made drilling out the weldings to fasten it. perfect fit same size of the pipe!

I am sure that you can find some other aftermarket inserts that will fit the stock pipes

I now got a bike that looks stock but with a great sound, and after fitting
UNIfilter, changing to 140 mains and 3 turns out on the idle screw the bike
runs great, and no popping at all.

Hunt up the holesaw thread. There is a holesaw circulating around with an extension welded on so you can cut out however many baffles you like without cutting the pipes at all.

Bmwhd,

Loud is not the reason for removing all of the insert, i did drill out my baffles using drill and saw but did not get the sound i wanted.

IMHO, removing it all and use aftermarket insert created a better "sound" for me but not louder.

Hey it works again!
I have Mikesr's hole saw. It goes out to ImOk
next. I had my computer crash (actual meltdown) so it's off as soon as I get to the Post Office today.

I was going to go with Todd's method drill out the end plate and then four holes in the second plate. But I took the end tube out (first plate) and it sounded just what I was looking for! The tone is incredible volume stepped up, but by far it is not too loud. I am going to leave it that way until spring and then see how I like it after a run at high speed. I did go for a 3 mile putt down a snow covered road (very slow) on the 7th of Jan, it was cold but it was great! Sounded awesome! So thats my story and I'm sticking to it.
ed

Todd,

I had the fore sight to make a recording of before and after the removal of the end baffle, as soon as I figure out how to make it work with the new forum, I will get it in here.

ed

Yep, basically what I did. I still had to persuade them a little to come out, but the hardest part was getting the brackets bolted up again. I ended up using one of those spring pick-up thing, that you get at the auto store, to hold the bolts while I tighted the nuts on the outside. I installed a set of 6" (or maybe 4") aftermarket baffles. I am vey pleased with the sound.

Guess I did this wrong the first time, it doesn't look like it took.

Anyway...here is what my stock pipes sounded like before and after I removed the end baffle "tube". I stopped there as I was happy with volume and tone it produced. Check it out youl'll get an idea if you are considering this.

If you have Windows media player click on this link and wait for the file to fully loadbefore you play it.

http://www.pressenter.com/~eddy1016/BA/OldNewBonnie.wav

If you have Real Audio player go here (smaller file)
http://www.pressenter.com/~eddy1016/BA/OldNewBonnie.ra

give you a good idea of what to expect. I would suspect that the more baffles you take out, the louder it gets and maybe deeper the "tone".

ed

With what Ed did plus the addition of four 1/2" holes in the next baffle upstream, mine is deeper but not much louder than his.

Is there any fine tuning you can do? I've got 2 baffles out but it's pretty jagged in the pipe. It sounds okay but not great, I still don't have the 70's triumph sound I am looking for. Should I get in there and do some filing or would that help?
thanks,

-PS

Dremmel tool on the outboard baffle, the second may be too far in? At least that is what I did. I stopped at the first one. A long rat tale file (Chain saw file) may work?

ed

what size jets are you running now?

I haven't been able to run it up long enough to check the plugs. Running from idle and reve, it seems ok, but I can't really give it a raod test till spring.

From what I hear, the best is to check the plugs for proper burn...so, I wait.

ed