Mufflers and Baffles

[Jeff]

On my 78 XS1100E..... the PO has removed the entire baffle from both mufflers leaving them pretty much straight pipe.

Is there an inexpensive replacement muffler that will work ok with the stock headers? Or..... is there anyone who sells a replacement baffle assembly that can be fit into the stock mufflers?

Currently... the bike is XSesively loud and runs poorly at low rpm. I assume that with the reduction in back pressure at low rpms... it is causing the mixture to be too lean.

[strom]

If you can take the pots apart, you can make your own... just get a pipe, make a LOT of holes in it, take some glass or rock wool or sth like that, fill it around and viola!

LP

[Jeff]

I mean.... these mufflers are EMPTY. The entire back end is a wide open megaphone that I can look down and see the inside of the header way back there. There appears to be absolutely nothing in there to restict exhaust flow and no visible means to support any sort of baffle that does not have some sort of rear plate or cone. When the bike backfires.... I get a nice jet of flame from the exhaust.

[Paul G]

In the tech tips check out installing HarleyFat Boy mufflers It may be what you need.

Paul

[strom]

OK Jeff, u're halfway there then.

Measure the diameter of the mufflers (ends) and get somebody to drill out a end-piece. It would be quite expencive (OK, 20$ or so), then drill holes so you can screw the ends in.

But before you do that, go to a muffler shop (not fancy, alredy made stuff... normal auto exhaust repair shop) and get a pipe with holes or sth (or drill em out yourself, more holes, more silence). The diameter should be large enough, to catch the front end of the muffler so that it doesnt bounce around. Have the end caps drilled out to the same diameter, so it would sit in the endcap (and not fall out).

Stuff a lot of stone/glass wool used for roof insulation all around the pipe, assebmle and you're all set.

At the end, it should look a bit like this... dunno how it'll turn out here:
__________________
/__________________|\ Place insulation here. Steel spunges work too.
/00000000000000000000\ A pipe with holes in it
|00000000000000000000
\00000000000000000000/
\__________________|/ End cap... have it made. But be sure that all measurements are correct first. It should go bout 1cm into the muffler so you can screw it in place with 3 screws.

God, I hope you can see sth from this pic. If you dont, I'll get you a scanned one that my friend made.

LP

[strom]

OK... finally some pics of the home-made exhaust system for the 78 XS11. The pics are a bit dark, but it was cheaper to borrow a friend with a dig. camera than getiing my own.

OK... here it goes...

The before picture....



And the after picture...
Here are the components...
The assembled pot on the left and disassembled one on the right. Muffler thingie is the ugliest thing on the pic. Cant miss it. The end cap is turned so you can see the back side. OK, cant see much, but there it is.




OK, this one is from the back... Theres a groove drilled on the endcap so the muffler-thingie can slide in and the end cap holds it in place at the back. The gray area inside the pot is temp. resistant paint. It should start rusting a bit later I hope.



Here are the header pipes. Just being painted with the temp. resistant paint. The top pipes are original and you can see where they were welded to the new pipes. The original material was weird and it didn't weld nicely, so I couldn't polish it to have it chromed.



Just so you see it can be done. It take some time and work, but it can be done.

[Jeff]

Well.... I came up with an acceptable solution to my gutted out mufflers. I found a set of Jardine slip ons on E-Bay for $99 and managed to win the auction since no one else bid on them. They should be here in a few days.

Now that I have the bike running good.... it's time to start working on the cosmetics a bit. Just refinished one of my rather banged up instrument housings and it turned out nicely. Now time to do the other. Hopefully I can find a set of side covers soon.... when I have the funds to get them.

[Jeff]

Just got my Jardine slip-ons from the ebay auction. I was expecting USED mufflers from the description. Unpacked them and found a bright shiny NEW pair of mufflers that have never been on a bike.... complete with crossover pipe. The picture of them looked good but I didn't expect them to be pristine. Especially since I got them for $100 for the pair.

Hopefully I will have time to put them on before the weekend and be able to ride without setting off every car alarm in a one block radius like I do now. LOL

[webbcraft2150]

The mufflers on my 80g finally went south. I bought 2 "extra long" mufflers from JC Whitney for $40 each. I cut the mufflers off just ahead of the crossover, got two adapters from Pep Boys to reduce the header pipe to fit into the new mufflers. Did a little bending and twisting of the stock mounts and got them to work with the new mufflers. Had to fab a new center stand stop (not hard). Also had to do some slight grinding on the brake pedal to clear the mufflers. They look stock, sound good, and I have not had to do any carb adjustments. JC whitney has several lengths of mufflers, in retrospect, I should have bought the shorter ones that would stop just before the axle, would make tire removal easier, but the longer ones end at the same place as the stockers. So far they are workin good.

[uaefiddler]

Muffler replacement - Crossover?

I won some Harley Sportster mufflers on Ebay - My XJ has rusted at the point where the mufflers connect to the header pipes - I was going to cut off the crossover section (badly rusted - with holes) and just connect up from the headers - Is it necessary to have that crossover tube? My Harley mufflers are set up with a crossover port on the side - Was thinking of closing them and just doing a "slip on" installation without a crossover- Will I have to rejet the carbs for this?

Any help is appreciated!

[Jerry]

Muffler theory says the crossover will help the XJ develope more low-end power. I doubt you would have to re-jet if you eliminate the crossover, but you may notice some low-end power loss. Then again, with the system as it now is, you may not notice any difference....

Jardine and some other after-market 4 into 2 systems kept the crossover, FWIW.

[uaefiddler]

Thanks
I think I'll setup a crossover - just to keep things somewhat as planned for the exhaust!

[strom]

Finally sealed the mufflers/headers properly... purring like new... now I gotta figure out why the bike idles at 3000 rpm... All I did was playing around with idle mixture screws and raised the fuel level to original specs.
Eh, well... tommorrow is another day

LP

[Geezer]

I'm going with Harley mufflers too. I just bought a set of nearly new Road King mufflers on eBay. With shipping they were just a little under $25. I'm still waiting for them to arrive but if they're as nice as the description, they should be like new. I think the guy said they only had 2 miles on them.

The Sportster and Fatboy mufflers are a lot shorter than the touring ones but that might be better if you want to be able to remove the rear axel without dealing with the pipes getting in the way.

I'll pist some pix when I get them done.

Geezer

[Geezer]

Did you make your own cones for the muffler bodies?

Geezer

Originally posted by strom
OK... finally some pics of the home-made exhaust system for the 78 XS11. The pics are a bit dark, but it was cheaper to borrow a friend with a dig. camera than getiing my own.

<Snip>

Just so you see it can be done. It take some time and work, but it can be done.