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Discussion Starter #1
Hello,
I have a 2019 MT09 with 87xx miles.
The bike suddenly fails to accelerate at close to or at complete WOT. The studdering is worse in the lower gears but highway pulls are a no go. The bike will continue with this behaviour until I release the throttle and reapply a lesser input.
I first suspected and changed the spark plugs but did not see a change.
Has anyone experienced such a problem?
Thanks!
 

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Why would you suspect spark plugs at 8k miles ,why would they miss fire at certain throttle ,it certainly sounds like traction control issue
 

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Discussion Starter #9
Why would you suspect spark plugs at 8k miles ,why would they miss fire at certain throttle ,it certainly sounds like traction control issue
Correct me if i am wrong, but the book suggests plugs be changed at 8k?

My understanding of internal combustion engines would suggest a spark or fuel delivery issue when the engine is at full song. Also an ignition/fuel system(s) would start to show a weak point at full throttle, high load

fuel is fresh 93 Octane,
the plugs were in great shape for their age, just starting to show electrode wear, (photo attached of worst plug)
159099


based on the lack of fault codes; i do not see traction control being an issue? I did not see a change when switched between modes.

The machine is still under warranty so i have called to have a diagnostic done.
 

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the wheel speed sensors can have issues but not throw codes, verify the traction control light on your dash is not on when it is occurring. if it is you likely have an issue with a wheel speed sensor
 

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Discussion Starter #11
the wheel speed sensors can have issues but not throw codes, verify the traction control light on your dash is not on when it is occurring. if it is you likely have an issue with a wheel speed sensor
Thanks cyclenut, alas the light stays off. You think the factory quickshifter could be messing with things?
 

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this is going to sounds crazy but a friend of mine had the same issue with his mt07 and during the winter a mouse had built a nest in his air box, was your bike sitting for a period of time before the issue started
 

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Discussion Starter #14
this is going to sounds crazy but a friend of mine had the same issue with his mt07 and during the winter a mouse had built a nest in his air box, was your bike sitting for a period of time before the issue started
Sadly no, I was able to ride often throughout the winter, I rode all day, suddenly when I cracked the throttle open, it started and hasn't stopped
 

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Discussion Starter #19
Have you tried the aps and tps sensors?
I have checked for condensation between connectors but did not see anything. I zapped them with a keyboard cleaner compressed air bottle and put it back together.
 

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I'd replace those plugs first, it's easy enough. Then look elsewhere if it doesn't fix it. Coils?
 
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