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Discussion Starter #1
Hello fellow riders!

I have an '08 'Blade with a Yosh R-77 carbon slip on. I bought the bike with the Yosh already on it. The bike is obviously rippin fast when you get above 5k rpm, but feels a little "groggy" any lower.

Do we think (or know) if a stock exhaust would make a noticeable difference in the lower RPM's? My only thought is that maybe the "high flow" slip-on exhausts relieve too much back pressure in the lower RPM's?... ONLY A THEORY. Don't castrate me for saying that- these threads get a little violent at times :nono: :rolleyes:

I THINK this was an older thread, but I'm hoping to rekindle this subject back to life. You '10+ Fireblade riders, lets hear from you too!!!

Thanks
~Matt
 

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Honda titanium exhaust valve.
Its regulated bybservo and throttle cables,it open the exhaust in different percentage depending what rpm range ur on,
Ex.. low end eexhaust opens 1/4. Full throttle all way, honda installed it to create better power. Flow,and more torque
 

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Honda titanium exhaust valve.
Its regulated bybservo and throttle cables,it open the exhaust in different percentage depending what rpm range ur on,
Ex.. low end eexhaust opens 1/4. Full throttle all way, honda installed it to create better power. Flow,and more torque
The 1000RR doesn't have it. So he won't lose anything.
 

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So do you guys think the bottom end power that's lost had anything to do with freed up back pressure?
Could have a slight effect but the changes are so minimal when changing a muffler that you should be be able to sort it out with changes to fueling (re-mapping).
 

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Discussion Starter #8
Could have a slight effect but the changes are so minimal when changing a muffler that you should be be able to sort it out with changes to fueling (re-mapping).
aka a power commander or bazzaz, something along those lines?
 

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yes when u free up exhaust, less back pressure less torque. but like he said PCV or tuner will fix it. everyone says to run a tuner after a can upgrade or air filter.
 

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My opinion here- don't worry much about it. I would certainly recommend tossing a PowerCommander on it, but that is due to the smoothness you can get from the throttle with it. I do not personally dip below 5k rpm very often as I like to be close to the start of the "real" powerband on my 954 (about 6500rpm). I tend to cruise right at 5k and have adjusted all my shifts to put me at a minimum of 4500rpm (MINIMUM) when I shift up.
 

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Discussion Starter #12
My opinion here- don't worry much about it. I would certainly recommend tossing a PowerCommander on it, but that is due to the smoothness you can get from the throttle with it. I do not personally dip below 5k rpm very often as I like to be close to the start of the "real" powerband on my 954 (about 6500rpm). I tend to cruise right at 5k and have adjusted all my shifts to put me at a minimum of 4500rpm (MINIMUM) when I shift up.
When you say "have adjusted all my shifts" you simply mean when you shift the bike, correct? Thanks, btw. lol :thumb:
 

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When you say "have adjusted all my shifts" you simply mean when you shift the bike, correct? Thanks, btw. lol :thumb:
Yes, this is purely my preference on when I shift as to keep the revs and power there for use if needed. A fuel controller can help to increase efficiency in order to avoid some loss of power/tq, but it isn't going to works miracles.
 

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Don't understand how PC can affect the exhaust back pressure or flow for that matter as it controls the fuel mapping into the chamber.
RR8 (an onwards I presume) have two valve in the silencer section as well as O2 sensor.
One valve opens at around 4k, the other above 6~7K. So the exhaust flow (and noise) is dynamically tuned depending on the engine rev.

I am not surprised your bike is running differently with this removed. It can be worse still if you have not got the O2 sensor
 

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I said nothing of it increasing backpressure or exhaust flow, only that it can help to optimize fueling which, in turn, leads to smoother power delivery and a slight increase in hp/tq numbers (if done correctly).
 

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Btw Alaska, I love those rear sets!!!! Are those stock? I don't assume they are, but haven't paid much attention to be honest.. just caught my eye when I was reading through this the first time and I forgot to say something. Looks like the Honda flying wing... awesome!
 

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Discussion Starter #17
I'm almost never in higher revs where the yosh exhaust could do some good. But I bought the bike with the exhaust on it. Stock exhausts don't bother me except for the sound quality... I much prefer the slip-on.
 
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