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Duckhunt
Guest
About 6 weeks ago I did a cheap Cat Converter removal I wanted to share. I did notice a difference in sound. Tone remains same, but it's crisper, far less back-rap, and although I did a gear change at same time it does pull harder. But I can't say how much was from Cat removal. It definitely freed up the exhaust. My wife and I both notice quieter trail riding because of less back-rap and because it's crisper.
Before beginning WELDING IS REQUIRED FOR THIS. Once you have the rear fender assembly and all the exhaust shields off, I sawz-alled the CAT out between the clamping points for the CAT exhaust shield which I reused. Make sure to leave enough pipe between clamping point and your cut to slide the adapters over and weld (if you want to reuse shield). There is a secondary shield that goes over the first CAT shield so it might not matter.
Once the CAT is cutout I used 3 adapters that were in stock at O'reilly's Auto Parts. They are $2.99 each. Their website is down so I can post part numbers later...
1.5"OD to 2"ID (1.5" goes to head/mid pipe)
2"OD to 2.5"ID
2.5"OD to 2.5"ID (used to make up rest of length needed)
If you do the math the adapters are not routed "correctly". Typically you'd want all the adapters to go into the next with exhaust flow, not over, like this. If you did it correctly you could clamp an adapter instead for a removable muffler. But this is what I did and my welds don't leak (yet!). You need to go from 1.35"ID to about 2.4"ID in if I remember correctly 7-8" length.
On the muffler end adapter 2.5"ID-2.5"OD, cut a .5"-to-0" angle on the 2.5"ID (larger) end, or about 11 degrees. Then piece all the adapters together in the machine, right were you want them. Use a welding blanket or something to cover the entire engine and wheeler, tack them all in place to each other and muffler. DO NOT weld 1.5"OD end to the small exhaust head/mid pipe. Then you can simply take the muffler off with the adapters tacked to it and weld complete on your bench. Then reinstall and weld the final 1.5" piece to the head/mid pipe. It took maybe 90 minutes total not including fender and shield removal since I already had that off. And maybe 5 minutes of run time to finish burning the UPC decals off the adapters!
Before beginning WELDING IS REQUIRED FOR THIS. Once you have the rear fender assembly and all the exhaust shields off, I sawz-alled the CAT out between the clamping points for the CAT exhaust shield which I reused. Make sure to leave enough pipe between clamping point and your cut to slide the adapters over and weld (if you want to reuse shield). There is a secondary shield that goes over the first CAT shield so it might not matter.
Once the CAT is cutout I used 3 adapters that were in stock at O'reilly's Auto Parts. They are $2.99 each. Their website is down so I can post part numbers later...
1.5"OD to 2"ID (1.5" goes to head/mid pipe)
2"OD to 2.5"ID
2.5"OD to 2.5"ID (used to make up rest of length needed)
If you do the math the adapters are not routed "correctly". Typically you'd want all the adapters to go into the next with exhaust flow, not over, like this. If you did it correctly you could clamp an adapter instead for a removable muffler. But this is what I did and my welds don't leak (yet!). You need to go from 1.35"ID to about 2.4"ID in if I remember correctly 7-8" length.
On the muffler end adapter 2.5"ID-2.5"OD, cut a .5"-to-0" angle on the 2.5"ID (larger) end, or about 11 degrees. Then piece all the adapters together in the machine, right were you want them. Use a welding blanket or something to cover the entire engine and wheeler, tack them all in place to each other and muffler. DO NOT weld 1.5"OD end to the small exhaust head/mid pipe. Then you can simply take the muffler off with the adapters tacked to it and weld complete on your bench. Then reinstall and weld the final 1.5" piece to the head/mid pipe. It took maybe 90 minutes total not including fender and shield removal since I already had that off. And maybe 5 minutes of run time to finish burning the UPC decals off the adapters!
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