Back pressure
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Joined: May 2009
Posts: 87
Likes: 3
From: ny
Back pressure
Looking to swap out my head pipe. I am seeing some posts about the m8 likes back pressure. Was looking for info on loss of torque. Iam looking at the full sac head pipe or the fuel moto head pipe. I have Vance and Hines slip ons that I will be using. Going to have Screamin eagle high flow round air cleaner. And street tuner. Also over winter going to do torque cam. From your experience will I get that torque drop off with either of those head pipes. Also will the cam fix any torque drop off. I also realize a lot of you dont like the cam but Iam just looking for a little more lower end power and want to keep warranty. I will be able to swap out stock head pipe if warranty work is needed m. Thanks
Seasoned HDF Member
Joined: Aug 2017
Posts: 7,322
Likes: 11,741
From: Omaha,NE
If you have a touring bike and are removing the cat by replacing the head pipe, your warranty is jeopardized anyway. If you're going to do that, go for a real cam and do it the way you want to.
Seasoned HDF Member
Joined: Feb 2009
Posts: 5,641
Likes: 1,985
From: Cleveland Zoo
Looking to swap out my head pipe. I am seeing some posts about the m8 likes back pressure. Was looking for info on loss of torque. Iam looking at the full sac head pipe or the fuel moto head pipe. I have Vance and Hines slip ons that I will be using. Going to have Screamin eagle high flow round air cleaner. And street tuner. Also over winter going to do torque cam. From your experience will I get that torque drop off with either of those head pipes. Also will the cam fix any torque drop off. I also realize a lot of you dont like the cam but Iam just looking for a little more lower end power and want to keep warranty. I will be able to swap out stock head pipe if warranty work is needed m. Thanks
Road Master
Joined: Aug 2011
Posts: 1,195
Likes: 299
From: midwest
Me, gutting the cat gained nothing in terms of either sound or juice. You’re money ahead staying with what you have. Mine’s a 17 107 with a heavy breather and CR460 cam. And actually, the Street Cannons have been great!
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,138
Likes: 6,163
From: SE Michigan
Fuel Moto or Fullsac are fine choices. Fuel Moto in particular seems to put a lot of research behind their products and are well regarded.
Last edited by Keithhu; Jul 16, 2020 at 06:20 PM.
Stellar HDF Member
Joined: Sep 2009
Posts: 2,113
Likes: 666
Keep in mind the w/ and w/o cat performance differences are mainly above where most people ride their bikes.
Most touring bike riders spend most of their riding time between 1500-4000. I typically cruise through town in 4th or 5th on level ground @ 1500-2000.
Just my personal riding experiences on my 50k mile 2017 RG w/SE447 and SE Cannon slipons.
Bob
Most touring bike riders spend most of their riding time between 1500-4000. I typically cruise through town in 4th or 5th on level ground @ 1500-2000.
Just my personal riding experiences on my 50k mile 2017 RG w/SE447 and SE Cannon slipons.
Bob
Last edited by FLTRI17; Jul 16, 2020 at 07:05 PM.
Stellar HDF Member
Joined: Sep 2009
Posts: 2,113
Likes: 666
Bob
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Road Warrior
Joined: Aug 2008
Posts: 1,895
Likes: 121
From: Southern WV
Truthfully, the cat isn't a hinderance in exhaust flow at normal riding RPMs. It does keep the exhaust a bit quieter. If you're worried about the warranty, stick with the SE parts and know that you are leaving performance on the table to keep the warranty. As far as backpressure, I've heard the same thing about the M8 but you can damn near see the exhaust valve from the end of my muffler and the torque will slid your butt back in the seat in every gear. RS468 cam and Fuel Moto tune.
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Tourer
Joined: Dec 2006
Posts: 299
Likes: 121
From: Potomac, Md.
Kazanimo, Hey for what it's worth, just gut your stock head pipe. Opinions differ on whether you gain performance and or sound. But you will lose the "Cat" heat... Spend the money you save on Mufflers, Cam and tuner. Good luck, which ever way you go. CSM-H
Tourer
Joined: Sep 2019
Posts: 430
Likes: 129
From: Harley ville
My advise it will be more rewarding to you to retain the factory head pipe also for exhaust scavenging. it really is a big deal. it will increase your throttle response. I do advise using a tts tuner and you will be glad you did. the power is smooth and it is dyno'ed it will run consistent and no adjusting with app on phone all the time. it is a professional way and be reliable. my dealer did it for me and kept my warranty.