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Since I've had my bike, I've noticed a slight hesitation or flatness in the powerband right around 4500 until about 5k rpm when I accelerate slowly like when in normal traffic. At worst, I'll give a light constant throttle input and the bike will stop accelerating at 4500rpm and I have to feed more throttle to push past it. At its best, the power goes just slightly flat around there and eventually pushes through on its own after 5k. Has anyone experienced this?
 

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I get this now and then, but only right after the bike is started. It seemed to start happening for me when I put in my Power Commander, but now that we're talking about this I haven't noticed it lately... and of course now that I said that it will happen tomorrow :)
 

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Don't worry Mase, mine does the same thing. I think it's normal. Once you're done breaking it in just fly through the rpm quickly until you're at your cruising speed and you won't even notice it. This bike likes to sing so keeping it down low will always feel 'off' compared to being higher up
 

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Since I've had my bike, I've noticed a slight hesitation or flatness in the powerband right around 4500 until about 5k rpm when I accelerate slowly like when in normal traffic. At worst, I'll give a light constant throttle input and the bike will stop accelerating at 4500rpm and I have to feed more throttle to push past it. At its best, the power goes just slightly flat around there and eventually pushes through on its own after 5k. Has anyone experienced this?
This sounds to me as an issue with the The air induction system (AIS) you need to block the system off,this will typically remove the majority of popping on deceleration that can be experienced with un-burnt gasses within the emission charcoal. www.spearsenterprises.com/yamaha-r-3.html Emission block off plates....

This is a scratch of the surface...but pretty much what I have seen....
 

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I was about to make a post about this. I've noticed it while riding to work the past few days. Mind you I'm only at 500 miles, so still in break in, but I noticed the same thing. My bike knowledge is limited so I wasn't sure if it was normal or not.
 

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if you have a look at the dyno run sheets for R3's you will note that there is a blip torque curve at the 5k mark, no rise in torque for about 500 rpm, I have felt this on my wifes R3 and its not as bad as some bike out there, R15 in particular its very pronounced at 3 to 3.5 k, and putting a free flow exhaust make it worse. Maybe a Commander V will help
 

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It's a good point to shift gears before that in normal traffic, or above that in track environments. A characteristic of the engine.
I know my suzuki had that point at 5-5.5k rpm.
from the factory, that was a lean point, to improve fuel economy where the engine would be revving most of the time.
Mine had a carburetor, so raising the needle a bit helped the issue.
on a fuel injected bike, it's much harder to do.
 

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I was thinking it was a bike thing. I'm a car guy so everything I know has at least 4 cylinders and 4 wheels, this whole bike thing is new to me.

Cruising at 45 I'm right at 5k RPM. Cant remember if its in 5th or 6th though for me to avoid 5k while cruising. No dash lights, a little extra input on the throttle makes it go away, still averaging over 60 MPG on my way to work, and seeing this on here makes me feel much better about it being a normal thing.
 

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I have this behavior too and it sucks. My carburated bikes didn't had it.
Does someone checked the sparkplugs gap?
I'd really like to solve it.
tks.
 

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Since I've had my bike, I've noticed a slight hesitation or flatness in the powerband right around 4500 until about 5k rpm when I accelerate slowly like when in normal traffic. At worst, I'll give a light constant throttle input and the bike will stop accelerating at 4500rpm and I have to feed more throttle to push past it. At its best, the power goes just slightly flat around there and eventually pushes through on its own after 5k. Has anyone experienced this?
I had the EXACT SAME problem a week ago before I visited my mechanic. We discovered the sparkplugs are semi-burned due to me always using 100-octane fuel on hot summer days. Switched to 91-Octane and Replaced my sparkplugs. Ran like Brand new again. 100% sure it was the plugs because it was the ONLY ONE we replaced. REPLACE YOUR SPARKPLUGS!
 

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I have noticed this on my bike every morning on my first run through the gears. I saw a dyno chart from one of the exhaust companies that looks like the power band dips around there but I could be crazy. Haven't noticed it after the bike is warmed up tho.
 

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BINGO! I removed and cleanned out my spark plugs, the falures reduced arround 70%, because I still had some high octanage fuel in the tank. The best to do is spend all the high octanage gas first, and than install brand new spark plugs, or make a very good cleanning on it with a sandpaper number 280 or 600, or even an stailess steel brush.
I'll change mine for iridium later.

To remove the spark plugs it's necessary to remove the fuel tank. Be carefull on this procedure. It is not necessary to drain out the fuel, but how less fuel, the better, because will reduce the tank weight. You'll have a little gas leakage, arround 10ml, when disconnect the tube that brings the gas to the injectors, so put some tow under the plug before disconnect it.
The spark plugs tool is 16mm size and has to be long, because it goes inside the engine head arround 12cm.

I'm not a mechanical, so I can not blame myself for any mistake during this procedure.
If you don't feel comfortable to make it by yourself, please bring the bike for any good service center.

Zachie69, thank you.
Good job for who will try this at home.
 

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I have noticed this on my bike every morning on my first run through the gears. I saw a dyno chart from one of the exhaust companies that looks like the power band dips around there but I could be crazy. Haven't noticed it after the bike is warmed up tho.
This is normal behavior while the engine is cold, don't worry. :D
 

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Guys, i think the spark plugs cleaning was just a placebo effect. After some days the failures returned. I don't know what to do anymore. If someone have any other idea, please share.

Thanks
 

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Guys, i think the spark plugs cleaning was just a placebo effect. After some days the failures returned. I don't know what to do anymore. If someone have any other idea, please share.

Thanks
Marc, what your experiencing is not a failure at all. If you ride the bike hard, cranking through the gears at full throttle you will not really notice any flatness in the power band. However if you ride slow through the gears you will notice between certain RPM intervals you will have less power. There is something called PEAK horsepower which is what the actual horsepower is rated at. You notice how they say this bike is
XX hp at XXXX rpm? That is because at a specific RPM the bike will have its most power. I think its around 7k+, anything before that will be slower or not have the same power. You cant have peak horsepower at every RPM. I hope this explains things for you. MY advice is to power throttle all day baby ;p
 

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I've noticed mine doing this after a cold start. I'm giving it more throttle and acceleration just stalls, then suddenly there is a rush of acceleration with a bit more throttle. I had a bad incident of it practically stalling then hitting back with all power, throwing me forward then backward.
 
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