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My, How to Build a Cheap Exhaust Muffler and Header thread

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So I dont feel like paying 500-800 in a full exhaust so I figured Id give a crack at building a full exhaust system for my DRZ for cheap.. I started off by picking up some

4" Diesel exhaust

1.75 Auto Exhaust

2 1.75 couplers

16 gauge 6"x18" sheet metal

And Exhaust packing

So Far I have $25 into the muffler, Packing is cheap..

I also used the design from the MRD exhaust that Ive been studying..

l_2b75e5fa2b1f41e6850636b8b396e487.jpg

I then cut the 4" exhaust down to 14" long

l_d3b8d354246b4130b56cbad91cd4dbfb.jpg

No was the time to trace the 4" diameter to the sheet metal

l_e1234044abbc4d15b8122269e6fb5091.jpg

I didnt get and pics of some of the setup but I cut out the 4" disk, and then cut a 1.75 hole in the ceter of that, you weld the disk to the coupler and then to the 4" tube

l_0e3c8fb2e4f64f6cbc441f9496173d3a.jpg

Next was the pain staking moment of measuring and drilling an ass load of 1/4" holes alternating all through the 1.75 tube

l_94d41dfdcb924ba188d824334ccd4b82.jpg

l_59ad89d914d148fdb8051deb0d2548af.jpg

After drilling I went and made another disk to fit on to the inner tube and also cut a 1" peice of the 4" tubing and removed 1/4 inch so the 4" tube can fit into the other 4" tube, weld

l_288eae3e0a304c1992823c200f933a34.jpg

l_9dd7671414ee4463900864800e848ecd.jpg

l_d55178ea3cd54321bb092ac439314769.jpg

And there you have it, in the last pick I dont have the inner section into the outer.. Still have more grinding to do to make it look nicer, also have paint and I will be trimming the inner tube alittle more but that will come when I start bending tube for the header and intermidiate tube.. More will come

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awsome work man!:) I love homemade mods:banana:

ingenuity at its finest right there, can't wait to see the rest

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I think you got the easy part done... bending the header is going to be a lot harder.

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Can't wait to see how it goes. Kudos on the DIY

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great job. i've thought many times about doing that very same thing. all i would need is to get the materials and, well, learn how to weld. :)

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So I dont feel like paying 500-800 in a full exhaust so I figured Id give a crack at building a full exhaust system for my DRZ for cheap.. I started off by picking up some

4" Diesel exhaust

1.75 Auto Exhaust

2 1.75 couplers

16 gauge 6"x18" sheet metal

And Exhaust packing

So Far I have $25 into the muffler, Packing is cheap..

I also used the design from the MRD exhaust that Ive been studying..

l_2b75e5fa2b1f41e6850636b8b396e487.jpg

I then cut the 4" exhaust down to 14" long

l_d3b8d354246b4130b56cbad91cd4dbfb.jpg

No was the time to trace the 4" diameter to the sheet metal

l_e1234044abbc4d15b8122269e6fb5091.jpg

I didnt get and pics of some of the setup but I cut out the 4" disk, and then cut a 1.75 hole in the ceter of that, you weld the disk to the coupler and then to the 4" tube

l_0e3c8fb2e4f64f6cbc441f9496173d3a.jpg

Next was the pain staking moment of measuring and drilling an ass load of 1/4" holes alternating all through the 1.75 tube

l_94d41dfdcb924ba188d824334ccd4b82.jpg

l_59ad89d914d148fdb8051deb0d2548af.jpg

After drilling I went and made another disk to fit on to the inner tube and also cut a 1" peice of the 4" tubing and removed 1/4 inch so the 4" tube can fit into the other 4" tube, weld

l_288eae3e0a304c1992823c200f933a34.jpg

l_9dd7671414ee4463900864800e848ecd.jpg

l_d55178ea3cd54321bb092ac439314769.jpg

And there you have it, in the last pick I dont have the inner section into the outer.. Still have more grinding to do to make it look nicer, also have paint and I will be trimming the inner tube alittle more but that will come when I start bending tube for the header and intermidiate tube.. More will come

Looks good...

Instead of bending tube, by mandrel prebent tubing made for header fabrication. Google mandrel bent exhaust tubing. Get steel, not stainless, far easier to work with.

Also, you can buy stuff called perforated tube to save you the agony of making a core in the future :) .

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That's looking great, good luck with the header.

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Im looking at doing the header into 2-3 sections and weld them together after mocking it all up, Ive got a mandrel bender so Im going to go that route rather than ordering the kit and having to spend more money than necessary

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i dont have a drz, but i really like this, it would be interesting to see it on the dyno compared to stock and other brand's systems, even if it doesn't make as much power as say an mrd system, if its more than stock its worth it in my bike, especially for how little money you have into it. good gas your way for your ingenuity and showing others :)

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Nice job on the home made.

I just finished adding my own baffles to a UK spec E exhaust system, so the noise performance is now the same as the stock UK SM system. It's now a semi reflective / semi disruptive flow system.

Using the noise meter on my phone, these were the reading, all taken from the same place in my garage, approx 5ft away at 45degrees to the exhaust outlet & 1ft above the exhaust level.

Standard SM

Idle 83db Max 113db

Standard UK E-exhaust system

Idle 100db Max >114db (my meter only reads to 114 db & it was painful to be in the room with it) This max level could have been from the pops on deceleration, as the UK system is basically an open can. When I was careful & wound it up & down slowly, so no pops, it still topped out at 114db.

Modified E-exhaust

Idle 84db Max 112db :) (50% throttle sustained 97db)

The flow still feels much stronger than the standard system though, only the dyno will tell, must get it booked for a run. it's now got a 31mm outlet compared to a 25mm outlet as standard.

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Nice! Please post up video so we can hear it when your done. I am very interested!

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