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Discussion Starter #1
Hello fellow enthusiasts! Its been a while since I've had to visit this site for the wealth of knowledge in here, but I need your help again.

Past issues aside, this bike has been a blast to ride and generally worry free. However, upon some of my last rides, I've noticed that I start to lose power above 7 to 8k RPMs. She pulls like a freight train from idle all the way through the mid range, then kinda looses all that 'umph' she used to have.

Sometimes though, the bike will 'kick' back on at around 9k and pull to 10.2, sometimes not. Sometimes she'll stutter all the way from 7 to 10.

On one run I was holding the throttle pegged in 3rd gear WOT, and it was barely climbing slowly to 7, then 8, maybe 9, and then I ran out of road.

I'm well aware of the flat spots and power losses these bikes can have, but this is a noticeable enough issue since this has not happened up until recently.

I'm also well aware of the 'soft rev' these bikes have and that's already been modded. I double checked the connection there, dielectric grease, secured the wires, etc. to make sure it wasn't loose. It doesn't 'feel' like the limiter, especially since this doesn't happen 100% of the time.

Things I've tried:

Check the soft rev mod
Removed the PC3USB
Reinstalled the PC3USB and reloaded the map
Fresh Gas (non eth premium, ran a whole tank through)

Ideas?
 

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I've been dealing with a similar issue lately. Replaced the coils (original) and plugs (6k miles old) and that restored the pep in the bike.
 

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Discussion Starter #3
Interesting. I know this bike just loves a good plug change (I only use NGK Iridium), but I figure that would affect the whole range, not just the top end.

Worth a shot at least, I'll pick some up and give it a whirl. I also have some spare coils hanging around, I'll try swapping those too.

Anyone who's had fuel metering issues, FPR aside, could this also be a fuel flow problem? I have no issues with cold starts, idle, or any other range. Just WOT / High RPM combo. Perhaps not enough juice up there?
 

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i had that problem to as well last year. come to find out it was a loose coil connection after pushing my bike home a couple of miles and then taking it apart. i agree with spark issues.
 

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Discussion Starter #5
Kicking this back to the top. Took the advice in here and changed the plugs and took her for a ride. The bike revved a bit 'smoother' but my problem did not go away.

I did a little more playing around on it and here's what I've found:

Intermittent power loss at WOT, almost feels jerky, sometimes it'll 'catch' and push me forward.
It's near or at WOT where the problem happens. I actually rev 'better' if I'm at 3/4 throttle as opposed to WOT where it bogs/jerks.
I can recreate the problem more often when the bike is warmed up, but I've had it happen at the start of a ride too.
I did not get a chance to change the coils yet (I need to get a good pair), but would a bad coil be intermittent like this?

On a side note, the fuel pump makes some squeaking noise when I prime it, and sometimes while it's running. I'm wondering if the pump is dying and cant supply all the fuel needed.

Any more insight would be helpful. Thanks guys.
 

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Discussion Starter #6
See now this is frustrating. I just went for a ride and it ran clean, powerful, smooth, strong. No issues. Best it's run in a while.

So I guess I can say it happens after either a) heating up somehow (I got the bike to 210 just to ensure full warm up), or b) a duration of time passes.

I hate tracking intermittent problems. Coils overheating?
 

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Did you get this problem figured out? In my experience (not with the rc) both your fuel system and ignition system will be under the most demand at full power and rpm. Are you able to rule out the fuel system by monitoring fuel delivery pressure while test riding it? Could be fuel pump, fpr, or filter related. Would be nice to rule that stuff out before throwing parts at it. Im not certain what the fuel pressure should be at or if its manifold pressure referenced. I dont have the manual for this bike yet but my guess is fuel pressure should be around or a bit over 30psi. Also since you changed your spark plugs and noticed it running a bit smoother but not affecting your problem, would also lean me more to suspect fuel. A weak ignition system on the way out will usually show a bit of improvement with fresh plugs, indicating you are on the right track.
Im sure that you probably got it fixed by now though, what was it?
 
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