There is no appreciative gain in hp by taking out a cat. The exhaust gases will flow better but it was designed to baffle some sound and burn any remnants of unburnt fuel in the exhaust gas..
Oh, great! Now I better call every drag racer and classic car and muscle car owner I know and tell them they might wanna put their cats back onto their 3-inch exhaust because they didn't gain a thing by removing it.
I got into this arguement with someone else in another forum one day. My question (that nobody could answer) was that if removing a cat makes no difference what so ever in flow or power, why does everyone with cars take theirs out the first chance they get? Leaving a cat in is like running 3-inch exhaust pipe through stock mufflers. It just makes no sense. You're defeating the purpose of doing all you can to get more flow. Sort of why all the aftermarket mufflers for bikes and cars having bigger ports through them. For added flow. Some of us don't worry too much about unburned fuel. But every time I hear or read about someone claiming NOT having a flow-restricting cat, I want to throw up. And your 3 hp claim seems logical. But add that 3 hp's for removing a flow-restricting cat to any added hp you might get from aftermarket exhaust and mufflers and numbers start to climb.
Being Mr Car Photographer for 30 years, I've lost count of the literally thousands of car shows and drag races I've attended, not to mention how many new friends I've made over the years who are into performance and power. I can assure you they would ALL laugh at me until the cows came home if I were to get out my megaphone and make the announcement that removing a cat and freeing up the flow was a big waste of time and has not nor will it ever make any difference at all in power gains from the removal of something that restricts exhaust flow.
You get the point. We could go on and on and on about removing or not removing the cat. But all you have to do is go to ONE drag race or ONE car show and take a poll. Ask how many people left their cats installed but put in headers and Flowmasters or bigger exhaust. Then report the results back into WT.
By the way, the way I lifted my bike, as foolish as it may sound, is to use an engine hoist and a strap through the grab bar. It's not like the back end is super heavy. I never had to remove the hugger nor the entire shock. Just the top of the shock, swing it back, lower the swing arm, and turn the Y-Pipe. Of course I tried to just pick the bike up with one hand and hold it in the air for 10 minutes while I used the other hand to do all the work, but apparently I hadn't eaten enough wheaties that day to lift the back end of a 480 lb (wet) bike and hold it in the air for 10 or 15 minutes. My friend used the hoist to lift his 919 with no issues, so I did it. No issues. Hey, it's bolted into the frame.