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Discussion Starter #1
So I have a 2016 GSXR 1000 a guy brought in and it keeps hitting this early red line at 12k RPM's only when the throttle is at 100%.

If you hold the throttle at 95% or less lets say, it clears right past the 12k limit and goes all the way to the 14k red line with no issues. It only happens when your 100% maxed out on the throttle and yes it does it in each gear only on the street. I've only got to test this in 1-5 gears at 12k rpms because 6th on the street is too fast lol. Other than that the bike rides perfectly fine no issues. There are no check engine lights.

The bike is bone stock ATM so no PC or flashed ECU or quick shifter to get into the way. These are some of the thing I have checked/fixed to try to get this issue to go away. Swapped the ECU from another bike to see if that would change anything. The kickstand switch is no longer on the bike so the circuit is soldered together. No kinks in the fuel line. Replaced the fuel pump with a Schnitz pump and new filter. Basically sure its not a fuel issue. Checked the TPS sensor and it reads the -C00 so I asume that's correct also.

At a dead end on what else it could be. The only thing I can think of that wont throw a code and ride perfectly fine is maybe the cam position sensor but to be honest I'm not too knowledgeable on that. I'm pretty sure the crank position sensor would throw a code and the bike wont start. Also even if one of these sensors were to mess up while riding the bike shouldn't it throw a code or at least flash or so showing is wrong? Any help is appreciated.
 

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Captain Obvious ... because obviously it’s obvious
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No, you're not sure it's not a fuel issue. If you didn't do a fuel flow code, you have no idea what your fuel system is doing.
 

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Discussion Starter #3
No, you're not sure it's not a fuel issue. If you didn't do a fuel flow code, you have no idea what your fuel system is doing.
Fuel flow code?? By just testing the fuel pump and regulator with a flow/pressure gauge because yeah I did that and its good.

The bike does not fall flat when reaching the limit, its pulling hard and then instantly it feels like its a ignition cut type of deal.
 

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I know things... A lot of things.
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Early redline would imply that the motor behaves like it bounces off the limiter at 12K, but I assume you mean it tops out and stops accelerating past that. Just_Nick probably meant fuel flow test/check, but in any case note that if you just measured pressure with the engine off, or idling, and found it within spec, that doesn't say much more than that you don't have any leaks in the fuel system. If you haven't done so already, you should measure flow, as described in the service manual.

If that checks out, keep in mind that there could still be blockages at the injectors, which the test wouldn't detect. Apart from that, and speaking from experience, such a top-end power delivery issue, without any apparent problems at lower loads, could come about due to worn spark plugs.
 

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Captain Obvious ... because obviously it’s obvious
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Fuel flow code?? By just testing the fuel pump and regulator with a flow/pressure gauge because yeah I did that and its good.

The bike does not fall flat when reaching the limit, its pulling hard and then instantly it feels like its a ignition cut type of deal.
It's not a pressure-based test, it's volume based. The fuel flow test (not code) measures the volume the pump outputs in a certain time, because a pump that's restricted can feel like ignition cutting. Also, the falloff is not going to be linear unless it's only a minor restriction. Which also explains the ability to reach 14,000 RPM when you're not demanding the same amount of fuel.

The test is in the manual.
 
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