Drilling out cat
Road Master
Joined: Mar 2010
Posts: 943
Likes: 41
The sound level increased slightly, but not much, and it was a little throatier. I didn't notice any performance increase with just the cat cut out.
Road Warrior
Joined: Sep 2014
Posts: 1,271
Likes: 246
From: Columbia SC
Just drill it, dont over think it.
Most simple thing to do, dont even have to take the pipe off the bike.
1. Buy a 1.25 inch spade bit from Home Depot
2. Buy a 1.5 inch spade bit from home depot
3. Buy a 12 inch bit extension
Pull the mufflers
Drill out the CAT with the 1.25 (hold onto that dill! Its going to bind up in the CAT a few times!)
Once done with the 1.25 use the 1.5 inch bit to clean everything up
When drilling make sure not to go to far and hit the O2 sensors or be safe and remove them (I left them in)
When done with the 1.5 inch, make sure you verify that you got all the CAT out, this is easy to do. I simply used a tent stake and slid it inside the pipe and make sure its smooth/no resistance.
Towards the end I did start the bike once or twice to make sure I blew out any debris that the drill did not push out. Some use a shop vac.
Wear goggles.
To me personally the last step in using the 1.5 inch bit is a step left out by everyone and I think (not that I am right) that using the 1.5 inch is the way to make sure you got everything cleaned out...
1. agree, slightly increases the throaty sound and I like it
2. As far as heat, dont build up your expectations, sure removing an up to almost 800 degree CAT will help but its not going to fix your leg burning feeling, the leg burning thing is the super hot exhaust gases heating up the rear cylinder pipe and the rear cylinder pipe radiates that super heat onto your leg, if you move your leg up and forward that will most likely help more with that issue.
(still I am glad I got the CAT out, every little bit helps I think)
3. You will not notice any performance increase, not that I think anyway, though who knows, to me it sounds better for sure
Last edited by alarmdoug; May 11, 2018 at 06:04 AM.
Advanced
Joined: Jun 2009
Posts: 75
Likes: 1
Can you say you noticed any heat reduction on the right side?
Seasoned HDF Member
Joined: Dec 2009
Posts: 17,684
Likes: 6,062
From: Niagara, Ontario, Canada
I noticed a heat reduction, wish I had taken temperature readings before and after to put it out there. Maybe before someone does it, they'll think of doing that. My version was the window cut out on the back side.
Advanced
Joined: Mar 2016
Posts: 81
Likes: 22
From: Orange, CA
I decatted last year and it may be one of the best mods you can do. Bike sounds WAY better and it feels MUCH MUCH MUCH cooler. I decatted after a trip to vegas in the summer when I almost had to jump off the bike at a red light because the cat was so hot.
Tourer
Joined: Sep 2016
Posts: 368
Likes: 37
From: Montgomery, Alabama
Did the same thing. Cut out a big rectangle so that I could make sure all the cat was removed and walls smooth for good air flow. After that, tig welded it back shut with some stainless rod. A weld shop could do it for you pretty cheaply. It's a 10 minute job at most.
Road Captain
Joined: Jan 2015
Posts: 646
Likes: 167
From: chicago
sent mine to american custom products, they cut it in next to factory weld and removed cat, welded in a baffle to prevent any chance of o2 sensor crosstalk, welded it back together. $199.
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