New Exhaust System (part 1)

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Redblock
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New Exhaust System (part 1)

Post by Redblock » Fri Jun 07, 2019 5:09 pm

All,

So I have always disliked the factory pontoons (exhaust system) they are bulky, not stylish and a little too quite.

So after doing some research on various mufflers and muffler repacking materials and baffles. I started a new exhaust system project for my 2015 GU.

Parts.
2 Dime City Cycle 17" reverse cone mufflers
IMG_4062.JPG
1 ISW Stainless steel wool muffler packing kit
IMG_4067.JPG
2 Stainless steel exhaust baffles (Crumb Cups in the plumbing section of Lowes or Home Depot)
2 10" sections of 1 3/4 exhaust pipe
2 1" insulated P-Clamps (and 1/4 inch bolts, lock washers and lock nuts for each)

Mufflers-
I did put the stock exhaust on one side just to heard how loud only one of the reverse cone mufflers was. IT was loud, but sounded awesome at idle. I would not want that as a regular sound level. See the lack of sound insulating material on the DCC muffler.
IMG_4064.JPG
Knowing that the DCC/EMGO reverse cone exhausts are loud and have very little packing, I opted to repack them with the ISW Muffpack materials. The muffpack is a layer of Stainless Steel wool mat, covered by a layer of Fiberglass insulation mat. All reports I have read and videos I have seen show that the muffpack does significantly quiet down Reverse Cone mufflers that come from DCC or EMGO.
IMG_4068.JPG
Crumb Cup Mod - I also added what Ryca motors (Cafe Racer Conversion kits) calls the Crumb Cup modification. It basically is a poor man's muffler baffle. It consists of tack welding a Stainless steel Crumb Cup in place at the end of the baffle. See picture.
IMG_4063.JPG
,
IMG_4065 (1).JPG
Once the Crumb Cup is tacked in and the muffler repacked with the muffpack kit material, reinstall the baffle into the cone and attach the end cap to the muffler. Repeat for the other muffler.

Exhaust Pipe adapters-
Ok - Ural uses a non-standard exhaust pipe od. It is less than 1 3/8 OD. Which means, fitting a non Ural muffler requires reducers to be fitted. I looked at the reducers that can with the Mufflers and they left a lot to be desired. I think the weak point in the whole system will be the reducers. I also tied to get exhaust pipe adapters but was not happy with the selection. That being said, I took a muffler and one of the catalytic converters over to my local muffler shop (Hi-Flow Custom Exhaust). After scratching our heads and looking at the problem, the owner came over and said, rather than using reducers and adapters, that we should just weld a section of 1 3/4 pipe to the exhaust side of the catalytic converter. The pipe was measured to 10 inches and cut. We measured part of the catalytic converter that would be inserted into the pipe, marked it and cut off the excess catalytic converter pipe (we wanted to decrease turbulence) See. the picture below. The Welds were then cleaned up with a flap wheel . This part of the mod is fairly permanent unless you want to buy a new set of cats or delete them.
IMG_4059.JPG
So here is what everything looks like mocked up.
IMG_4069.JPG
IMG_4060.JPG
IMG_4070.JPG
I need to un-mock up the exhaust and paint the exhaust/cat pipes. Then I will get it all put together on Sunday.
I will post part II then and l will record what it sounds like, as well as posting the final photos. I think this is going to turn out well. If not I always have my stock pipes and I will just find replacement cats.

Thanks for following

Rob
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Redblock
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Re: New Exhaust System (part 1)

Post by Redblock » Fri Jun 07, 2019 5:10 pm

So far my total parts for my project are $160 total.

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Lokiboy
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Re: New Exhaust System (part 1)

Post by Lokiboy » Fri Jun 07, 2019 7:53 pm

You’ll have to post video. Nice work.
2011 Gear Up - "Erika"
Yorktown, VA

Mains: 127, Idle: 40, Needle: 1 shim
MKIII air filter
90,000 km and counting

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Redblock
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Re: New Exhaust System (part 1)

Post by Redblock » Mon Jun 10, 2019 1:59 pm

Lokiboy I posted the video's in my new thread "New Exhaust System (part 2)

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