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I decided to create my own slip on system so everything could be taken back apart. My system consisted of a 6" length of 1-1/2 diameter exhaust tube purchased at Pep Boys, a couple of pan-head screws and some Exhaust System Joint and Crack Sealant. The 1-1/2 tubing was a nice tight slip fit right over the header. I left the flange on the header applied a liberal amount of sealer and just butt fit the two pieces together. I drilled a 1/8" hole and locked the two pieces together with a sheet metal screw. The sealer forms a "weld-like" bond but it is one that can be cracked apart for disassembly.
The mufflers have an 1-1/2-ish intake. This is not a slip fit, my guess is its 1-5/8" or some crazy metric size. So I made a run down to Autozone to "borrow" an exhaust spreader. (Autozone allows you to borrow tools, just leave a deposit and bring it back within 5 days.) The plan was to expand the exhaust tube to get a good tight slip fit. The problem was the 1-1/2" expander wouldn't fit into the 1-1/2" exhaust tube they were the same diameter. I would need a smaller size expanded which they didn't have at Autozone.
I decided to go the other direction. I pulled out my Saws-all and cut two cross cuts the width of the blade into the new mufflers. These cross cuts allowed me to reduce the opening to a tight slip fit on the exhaust tube. The exhaust pipe goes in about twice as far as the cuts and bottoms out on the slip in baffle.
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Once it was all dry fit, I pulled the exhaust and drilled a 1/8" set screw hole in the muffler and exhaust pipe. Then I pulled it apart applied more Exhaust System Joint and Crack Sealant and put it all back together. Finished exhaust... no welding.
With two exhaust pipes in hand I pulled out the 1" wrap and proceeded to wrap the pipes. I was taught to start at the muffler and worked my way forward. This way the air is flowing over the seams not running into them. Think of it like rain going over shingles on a roof.
Two wraps at the base of the muffler and a hose clamp to keep it in place. I continued wraping by overlapping each wrap with 1/2 the width of the wrap and finished about 3" from the head of the exhaust. You need to leave room to get the exhaust clamp and clamp locks in place. I finished the wrap by crossing the last wrap under itself and carefully cutting off the "tail" with a box knife this in effect creates a knot at the end of the wrap. Then a second hose clamp over the knot keeps it from untieing.
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The end result is a cool old-school exhaust with a header pipes that could be reused to remount stock mufflers. These mufflers create a little deeper exhaust note and I think they sound pretty good! It'll be interesting to see if we will need to re-jet the carbs to make up for the lower restriction exhaust.
Hey, I have followed your blog for a few things and found it very useful/interesting (especially the Clubman install...). Anyways, what do you think about the shorty exhausts on the 200? How much louder are they actually than the stock exhausts, and did you ever find that you had to re-jet, or did you leave the carbs as-is?
ReplyDeleteNice looking bike. I have a '75 360t that I am slowly beginning to cafe....
Better make sure that your installed muffler will
ReplyDeletegive you increased engine efficiency, performance, power output, and simultaneously decreased overall wear and tear on the engines' components
Mufflers