I went to the website of the company that offers cat removal and saw a cut away view of the cat itself. That convinced me that the cat must go! Both for heat build up and sound. I was planning a slip on in the short term and complete exhaust long term, but now I've decided to save the money on the slip on and put it toward complete exhaust now. Thanks for the insight into the cat issue.

 

I just saw a video of a guy that used a hole saw with an extension. He bored out the cat on his bike. All he had to do was pull off the slip-on and run the thing in the pipe. You might want to search for the thread. I am pretty sure I saw it here.

 

You guy's can do what you want but unless you have some previous experience I would caution you against messing with the cat yourself. The company you referred to I suspect is Fullsac?? They are very good and very experienced at what they do. I agree with the concept of totally removing the entire system and install a new system without the cat. I doubt if you can install a complete new system without installing a tuner?? Maybe you can, but for sure you will need a system that accommodates the new small size O2 sensors which as you know have been moved down to the cat area on the 2010's. I have a 2010 Ultra and took off entire system and replaced with a D & D 2:1 with a tuner. Solves many issues. Good luck.

 

I drilled my CAT out on the advice of the HD Dealer techs back in Oct when I bought my '10 SG. Easy to do and ZERO problems and lots less heat.

 

With your post I'm rethinking total replacement short term. Did you use a hole saw or hog it out with a bit? Head pipes off the bike or in place? I might get out the chop saw & wire feed and take the "fullsac" approach but it's more work and maybe not justified to get it all. Did you remapp after drilling it out? Thanks for the help!

 

I have the D&D Boss Glide on my 2010 FLHX.

FTR - This comparison is to my 2008 FLSTN with Vance & Hines 2-1 Pro Pipe, S/E Stage 1. Sound was much better on the 2008 V&H.

However, considering I am comparing a complete exhaust ($$$) to a slip-on ($$), the performance is where I have the difference. I did not change anything else on the FLHX other than the Air Cleaner, S/E Stage 1

Dyno on the 08 FLSTN
MX Power 71.57 Torque 83.96

Dyno on the 10 FLHX
MX Power 72.56 Torque 87.37

*Since this post in April 2010, I upgraded cams & change pipes