Thoughts on Cat being restrictive......
Road Warrior
Joined: Aug 2010
Posts: 1,268
Likes: 8
From: Detroit, the asshole of America
It's not restrictive enough to reduce power on a stock or stage 1 bike. Do cams, compression, headwork, etc, and it starts to become a bottleneck. But, for the average person running around with slipons and the a/c swapped out, removing it gets you nothing on a dyno. Just posting pictures of what a cat looks like doesn't mean much, there is enough volume there to support what the engine is capable of pumping through it at WOT.
It will be cooler and the sound will be louder if you ditch it, though.
It will be cooler and the sound will be louder if you ditch it, though.
Seasoned HDF Member
Joined: Sep 2008
Posts: 20,880
Likes: 33,837
It's not restrictive enough to reduce power on a stock or stage 1 bike. Do cams, compression, headwork, etc, and it starts to become a bottleneck. But, for the average person running around with slipons and the a/c swapped out, removing it gets you nothing on a dyno. Just posting pictures of what a cat looks like doesn't mean much, there is enough volume there to support what the engine is capable of pumping through it at WOT.
It will be cooler and the sound will be louder if you ditch it, though.
It will be cooler and the sound will be louder if you ditch it, though.
Road Captain
Joined: May 2008
Posts: 563
Likes: 0
From: Kansas City, MO
I've got an '11 RKC. I put Rinehart 4" slip-ons on the bike. I left the stock head pipe in place and intact with the cat. I live in KCMO (hot & humid summers). I like the sound from the Rineharts. When sitting still (bike idling), it's hot, but not JUST from the cat, everything under my a** and the gas tank is hot. When I start rolling again, it's not bothersome. Simple.
There may be ways to boost HP or torque, but really, the bike moves my big a** where I want to go as fast as I want to get there. If I was going to race, I'd have bought a 'bussa.
There may be ways to boost HP or torque, but really, the bike moves my big a** where I want to go as fast as I want to get there. If I was going to race, I'd have bought a 'bussa.
Road Master
Joined: Mar 2010
Posts: 943
Likes: 41
I didn't make any inference toward power output. In fact I didn't notice any power increase at all. I merely stated that I noticed an increase in sound and not as much heat on the right side. To me, it was worth the cat removal for the heat reduction alone.
Seasoned HDF Member
Joined: Jan 2007
Posts: 20,616
Likes: 4,440
From: anacoco, la
when the dealer told you you had to reflash the ecm, what he really meant was you had to reflash 150 from your bank account to his.
Road Master
Joined: Apr 2010
Posts: 795
Likes: 1
WRONG !! HD stage 1 recalibration for correct VE when changing intake and exhaust. It also adjusts the timing as well as raises the redline. Well worth $150 if you are not going to do more than intake and exhaust. XiEDs ($100) would help the closed loop. Both items are a good combo for stage 1.
Seasoned HDF Member
Joined: Jan 2007
Posts: 20,616
Likes: 4,440
From: anacoco, la
WRONG !! HD stage 1 recalibration for correct VE when changing intake and exhaust. It also adjusts the timing as well as raises the redline. Well worth $150 if you are not going to do more than intake and exhaust. XiEDs ($100) would help the closed loop. Both items are a good combo for stage 1.
but my point is, just removing the cat does not require a reflash by the dealer. now with the stage 1 done, should he have some type of fuel management? sure, but again, not sure the dealer flash is the best way to go about it. no matter what, the dealer flash has to stay within epa mandated parameters. that means, still lean.
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Road Master
Joined: Apr 2010
Posts: 795
Likes: 1
i'm not sure that the dealer flash actually changes the timing, have heard some say it does, and some people who really should know say it doesn't.
but my point is, just removing the cat does not require a reflash by the dealer. now with the stage 1 done, should he have some type of fuel management? sure, but again, not sure the dealer flash is the best way to go about it. no matter what, the dealer flash has to stay within epa mandated parameters. that means, still lean.
but my point is, just removing the cat does not require a reflash by the dealer. now with the stage 1 done, should he have some type of fuel management? sure, but again, not sure the dealer flash is the best way to go about it. no matter what, the dealer flash has to stay within epa mandated parameters. that means, still lean.
Elite HDF Member
Joined: Apr 2007
Posts: 3,766
Likes: 16
From: Roseville, CA
WRONG !! HD stage 1 recalibration for correct VE when changing intake and exhaust. It also adjusts the timing as well as raises the redline. Well worth $150 if you are not going to do more than intake and exhaust. XiEDs ($100) would help the closed loop. Both items are a good combo for stage 1.
Running great does not always mean fully optimized and tuned.