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So I just recently did the Reflash of my 19 R1. To me, I’ve always been a fan of shorter pipe that tuck away rather than the side mounts. Many have said the crossplane engines do not like the short pipes and benefit more from longer length. Someone support this claim or have more info on it?
 

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Venom X/O
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I think the best support for this is the midrange gain from the graves EV exhausts that show the midrange increases greatly as back pressure increases. It’s something like 30hp in the midrange
 

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So I just recently did the Reflash of my 19 R1. To me, I’ve always been a fan of shorter pipe that tuck away rather than the side mounts. Many have said the crossplane engines do not like the short pipes and benefit more from longer length. Someone support this claim or have more info on it?
Lots of variables, cam profiles, engine compression… but a rule of thumb: longer cans = more hp at the top
Short cans > mid range torque
 

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ive been told my modded Comp Werkes pipe is making me lose power all over . It’s basically that exhaust , race filter and a reflash.
Depending on how interested you are in the reason for that possibly accurate statement you could or could not look into reversionary exhaust flow and exhaust design.

Very short (think top fuel cars) to short pipes (headers with collector) give better high end power at sacrifice of low and mid tq and hp.

Mid (that’s you) to long (stock) will produce back pressure. This effect helps with cylinder fill because of valve overlap and increases low and mid tq and hp while sacrificing high end power due to pumping losses and air charge temp increases.

Pipe diameter also has great influence. A large long pipe looks shorter then small mid pipe to the air compressor that is your engine.

Sadly there is no solution that is great across 14000 rpm. More like you can design one for great performance over 1000-2000 rpm and ok performance for 1000-2000 on either side. So a happy 3-6k wide band , say 4, where she really can breathe. If your a redline performance kind of rider than you stand to loose out on that top end ok portion. Pick the exhaust that gives you power where you want it.

That’s the short version.

Choose carefully that’s one them expensive parts.
 

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ive been told my modded Comp Werkes pipe is making me lose power all over . It’s basically that exhaust , race filter and a reflash.
@RedWolfR1, can you elaborate on which comp werkes exhaust you have and what was modded? Does your bike backfire on decel?

I have a similar setup on my 15 R1 (flashed, comp werkes, filter, block off plates) and the back firing is annoying. Was told exhaust leaks or improperly installed block off plates could cause this but I doubt they're the issue. Back firing is not consistent. Was also told by my tuner that what I most likely need to fix the back firing is FT-ECU's "active tune" set up. it actively adjusts fuel and air as needed. Makes sense I guess, especially because my flash deleted O2 sensors and runs a single fuel map.

Interested to hear how your bike runs with your current setup and If you've experience issues like I have.
 

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Not an R7, next best thing!!
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The backfiring will not be fixed with the activetune. I have it on my bike, with smog blocks, race filter, and a Graves slipon. She pops a lot on decel at pace, not so much on the street though. If you want to hear the pop, which is really not that loud...just jump to minute 3:18.
 

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Unacceptable
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I think the best support for this is the midrange gain from the graves EV exhausts that show the midrange increases greatly as back pressure increases. It’s something like 30hp in the midrange
I can almost guarantee that the midrange gains are nowhere near that. :LOL: A much more realistic gain would be more like 6-8 bhp at best.

I'm running the EVR on both my R1 and my MT-10. Ecu was flashed by 2WDW.
 

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Venom X/O
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I can almost guarantee that the midrange gains are nowhere near that. :LOL: A much more realistic gain would be more like 6-8 bhp at best.

I'm running the EVR on both my R1 and my MT-10. Ecu was flashed by 2WDW.
Graves posted dyno’s. Check them out, I could very well be wrong but that’s what they were claiming at the time
 
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