Decatting header
Grand HDF Member
Joined: Jul 2007
Posts: 3,723
Likes: 8,459
From: Bates County MO
Seasoned HDF Member
Joined: Jun 2014
Posts: 5,448
Likes: 6,275
From: pacific northwest
Took me about an hour to drill out the cat on the RGL, and did a stage 1, main reason I removed the cat is my wife felt so much heat on her leg on a hot day. it runs great with the tune Fuel Moto sent for my PV.
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Grand HDF Member
Joined: Aug 2017
Posts: 3,573
Likes: 886
From: Nowhere
Thank you for all the replies. So initially i thought about cutting the window to remove the cat while I believe most of folks here simply drilled it out from the back without the need to weld anything?
Also does anyone did it without removal of the headed or this is rather not doable?
If I can avoid welding and removal from the bike it would be my ideal solution but not sure if I am not asking too much.
Also since my bike is stock will I need a tune after this modification since it was mentioned air flow is rather same as stock?
Also does anyone did it without removal of the headed or this is rather not doable?
If I can avoid welding and removal from the bike it would be my ideal solution but not sure if I am not asking too much.
Also since my bike is stock will I need a tune after this modification since it was mentioned air flow is rather same as stock?
Seasoned HDF Member
Joined: Dec 2009
Posts: 17,684
Likes: 6,061
From: Niagara, Ontario, Canada
Thank you for all the replies. So initially i thought about cutting the “window” to remove the cat while I believe most of folks here simply drilled it out from the back without the need to weld anything?
Also does anyone did it without removal of the headed or this is rather not doable?
If I can avoid welding and removal from the bike it would be my ideal solution but not sure if I am not asking too much.
Also since my bike is stock will I need a tune after this modification since it was mentioned air flow is rather same as stock?
Also does anyone did it without removal of the headed or this is rather not doable?
If I can avoid welding and removal from the bike it would be my ideal solution but not sure if I am not asking too much.
Also since my bike is stock will I need a tune after this modification since it was mentioned air flow is rather same as stock?
I don't believe you can get all the cat out clean with a drill. I cut the patch and cleaned it out like a kid licking the inside of a chocolate ice cream bowl
Last edited by kel03; Dec 11, 2023 at 06:51 PM.
Road Master
Joined: Jun 2015
Posts: 804
Likes: 1,510
From: Bloomington, IN
Sheffer Performance in Evansville Indiana has many builds using the stock decatted header on the M8 with great results. Even some 124/128 builds pushing big power.
A majority of my friends and I use the stock decatted header as well. From mild stage II's like mine and a couple 128's. I can't say if we switched to Fullsac we'd gain 3 horsepower or whatever, but our numbers are right on par with other builds using aftermarkets headers and the torque curves look good. I'd decat and not worry about buying Fullsac.
A majority of my friends and I use the stock decatted header as well. From mild stage II's like mine and a couple 128's. I can't say if we switched to Fullsac we'd gain 3 horsepower or whatever, but our numbers are right on par with other builds using aftermarkets headers and the torque curves look good. I'd decat and not worry about buying Fullsac.
Stellar HDF Member
Joined: Aug 2020
Posts: 3,159
Likes: 2,202
From: College Station, TX
I recall someone on the Forum saying they removed the cat while the header was on the bike. But that it would have been easier and faster (not including the removal and reinstall time) if it had been removed. I think it was mentioned in the cam testing post from Steve Cole and $tonecold a few years ago.
Mine was removed because I installed a cam at the same time. And FWIW, the header is not difficult to remove.
Paul
Mine was removed because I installed a cam at the same time. And FWIW, the header is not difficult to remove.
Paul
Cruiser
Joined: Aug 2012
Posts: 240
Likes: 53
From: pontiac
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