HarleyTechTalk

I've yet to see the sense in removing a perfectly good cat. Does anybody have numbers to show measurable gain/loss in doing this?

I'm guessing any difference would only be felt at higher rpm due to whatever flow restrictions the cat imposed.

I believe the real rationale for pulling them is to increase volume and /or tone. Heat is a issue for some, but personally I ride solo and that's never been a problem.

You might gain a couple HP at high RPM, and you will remove some heat. The heat issue is the biggest reason mine is gone.

Quote from: PoorUB on July 13, 2017, 07:47:32 AM
You might gain a couple HP at high RPM, and you will remove some heat. The heat issue is the biggest reason mine is gone.

Same here.

I have a 2013 street glide w/o cat and installed RC Mufflers. Son in law has 2014 street glide with cat and RC mufflers. Noticeable difference in sound & heat! Frank

Noticeable reduction in heat  My backside could not find any difference in horsepower though.

Some folks found early on if they tuned a cat equipped bike richer, it got hotter real quick. Easiest way to prevent that was to de-cat the exhaust. Most sheets show a measurable gain above 4K by removing the cat.

Did  mine  for  the  heat may get  one  or  two  hp that's  all 

Quote from: Boe Cole on July 13, 2017, 09:20:10 AM
Noticeable reduction in heat  My backside could not find any difference in horsepower though.

Gonenorth and I both have 2016 Limiteds. His is stock, mine has a gutted stock head pipe, Fulsac recore kits and returned with a TTS. Last week out on Montana we pulled up a step grade, purposely running in sixth gear. He lost some speed but his bike leveled off about 65 MPH. I was able to pull up on him and drop off the throttle and run along side him at part throttle and could roll on the gas and easily accelerate where he had all he could get. There was definitely a difference in power. Not sure what RPM we were at but running 65 in sixth so around 2500 RPM.

I agree with Poor from the get-go,,, bottom line get rid of the cat & GET RID of some heat. If the cat holds in "sound" it holds in HEAT as well .GET RID OF THE CAT. then get a good tune. All is good with life 

Quote from: PoorUB on July 13, 2017, 07:47:32 AM
You might gain a couple HP at high RPM, and you will remove some heat. The heat issue is the biggest reason mine is gone.

When you sit at a traffic light in 85* & 90* temps you can tell that some heat has been remove.......Ha......balony

Quote from: Panzer on July 13, 2017, 07:12:07 PM

Quote from: PoorUB on July 13, 2017, 07:47:32 AM
You might gain a couple HP at high RPM, and you will remove some heat. The heat issue is the biggest reason mine is gone.

When you sit at a traffic light in 85* & 90* temps you can tell that some heat has been remove.......Ha......balony

Believe it or not, but in stop and go traffic with the cat in place I have dropped the jiffy stand and got off the bike to cool off my legs. After the cat was removed I never felt the need to bail off the bike.

We ran 250 miles in 90 degree heat a few weeks ago and I thought my inner thighs were going to burn up. Last week we ran hundreds of miles in 100 to105 degree heat and my inner thighs were not as hot as the previously mentioned trip. The bike was more comfortable, heat wise.

My 12 EG was undeniably hotter with the cat but the same time I installed a cat free head pipe I also loaded a fatter PV tune.

I've removed the cats on 3 different 2010 bikes and tuned them, it helped some with heat but not much. I have a box stock 2015 RK and it is as cool if not cooler than the tuned and gutted 10's. I did have a 2007 Ultra that was a heat monster. I did all the stuff and the only way I got rid of the heat was to get rid of the bike.

Something else to consider. The exhaust will be considerably louder. I went thru several sets of slip-ons trying to get my 2010 Ultra to sound better. When I put the cat-less headpipe on, suddenly my Rush pipes were almost too loud-lol. Luckily they have interchangeable baffles and I was able to buy a smaller set to quiet it down some.

I don't like loud exhaust. I don't mind a little rumble, but the loud barking or cracking exhaust I don't like. I will put hundreds of miles on in a day and the loud exhaust wears me down. The 2" Fulsac recores just rumble nicely while running 80 MPH down the slab. I had a set of mufflers on my '05 years back, guys called them SE 98B's because of part number and they were popular. I got a set cheap, had them on the bike for 500 miles took them off and sold them, too damn loud!

Quote from: PoorUB on July 15, 2017, 05:51:38 AM
I don't like loud exhaust. I don't mind a little rumble, but the loud barking or cracking exhaust I don't like. I will put hundreds of miles on in a day and the loud exhaust wears me down.

Same here, Krusher Mellows with the baffle drilled to 3/4" seem just about right. Not really noticeable at all until I really wick it.

Just getting rid of the cat reduces the heat some, but combining cat removal with an appropriate flash (like a canned map) or better yet, a good tune, will reduce the heat a lot more.

I've been fighting this with my 2012. Finally went with Vance & Hines Power Duals, SE Street Cannons, and a few rounds with my SEPST, and it seems to have helped a lot. Looks like about 75 to 80 degrees drop in temperature on the rear head. I've been measuring right next to the spark plug.

Needless to say, the SEPST has been a learning experience. I'm still thinking in terms of jetting a carb.

I had a 2010 Ultra..installing a Fuel Moto catless headpipe made a big difference in performance.