[FiRE Comms]

so the baffles of my reverse cone have shaken lose and I've been considering exhaust options.  Does anyone know the internal diameter of the stock head pipe?  I've been considering scrapping the muffler all together and installing a baffle in the head pipe?  any thoughts? 

[ace.cafe]

The header at the head joint is 1-3/8" diameter. I am not sure what it is at the tail of the header.

However, baffling the tail end of the header pipe would not be a good idea from a performance point of view.

[HUdson51]

By putting a baffle in the header pipe I believe you run the risk of burning an exhaust valve and would cause high back pressure ? Am I correct in that assumption?

[FiRE Comms]

thanks guys, that's why I ask...

[GSS]

Chris,
There are plenty of good options for a C5.....Harley softail, Silman short bottle, megaphones.....etc. available on EBay, Hitchcocks, NFG. You will quickly figure out the pros and cons for each simply by scanning through 5 years worth of C5 muffler discussions!  As the others have pointed out, a baffle in the header pipe isn't a good idea. Almost all 1 3/4" mufflers will need a little shim to fit tight on the header pipe. Thanks.

GSS

[Sectorsteve]

Great thing about the Harley mufflers is that most the sellers on ebay sell 2 as they come in pairs. Cheap too

[Scotty Brown]

I installed a HD 1200 Sportster muffler ( 80 dba ) and have never looked back.  It does require a shim to fit pipe and an exhaust shield to cover the weld on the down pipe.  Very easy install, good sound, and no changes to the ECU.  They are cheap on e-bay or craigs list.  I got mine for fifteen bucks.

[suitcasejefferson]

Just out of curiosity, I keep seeing in these exhaust threads where welds are breaking loose on Enfield exhaust pipes. This seems to happen not only with the stock pipes, but the EFI pipe, most other aftermarket pipes, and even Harley pipes, which are designed to withstand vibration. Is this just my imagination, or is it really an issue?

[GSS]

A couple of folks have reported breaks in their stock C5 bazookas, one maybe had it happen a couple of times. I have run 5-6 different ones on my 2 UCEs with no issues. The Silman sounded great but was a smidge too loud and turned all shades of gold and blue. HD had the best fit/finish/cat converter/nice thump.....plus was less restrictive, so that was the final choice for my C5.  The AEW was horrendously loud on my GT and needed a baffle for sanity.  I have a factory racing silencer that is waiting to self install......but never had any issues with mufflers cracking. Thanks.

GSS

[The Old Coot]

Just out of curiosity, I keep seeing in these exhaust threads where welds are breaking loose on Enfield exhaust pipes. This seems to happen not only with the stock pipes, but the EFI pipe, most other aftermarket pipes, and even Harley pipes, which are designed to withstand vibration. Is this just my imagination, or is it really an issue?

After look at the "Welds" I can well believe it. The "Welds" on my pipe look like they were done using a car battery and coat hanger. 

[Arizoni]

I have read about a number of welds failing on the OEM muffler (silencer), (Bazooka, torpedo, telephone pole, use your imagination).

The sheet metal is very thin.  The welds are not the best.  The front of the muffler gets very hot because a catalyst is located in that area and often overheats it.

I don't recall ever hearing about even a single case where the actual downpipe between the cylinder head and the muffler ever failed.

[gremlin]

HD muffler.

[HUdson51]

Can someone post a picture of a Harley pipe installed on a bike? I am curious about how it looks and exactly which model works best as a donor?

[Gesewa]

Here's mine with a HD sportster muffler.  Not sure about the year it's from, but old enough to not have the crossover ports.

[dickim]

Just fitted the Pwr / k&n / silencer combo and found the silencer ( slightly coned one) is too big for the header pipe & no shims / sleeves - anyone know the sizes to try to buy before I start trying to make my own 

Fitting pwr unit was methodical and straightforward apart from injection connection not "clicking" home - so from fingers crossed, and started & idled immediately.