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Discussion Starter #1
So its been a while since the last post I made. I been through the bike from top to bottom with new mods and the last thing I wanted was my bike to die on me while I'm riding.... long behold it did, mid acceleration in 4th gear and my bike loses all acceleration and power. So I pull over and check things out and this is what I came across.
25929
It was a brand new spark plug (1 day) and gapped to the recommended spec. Why did it weld itself close??
 

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Why do i see a .... 9Y ?

Do you have the right plug in it ...

SPARK PLUG.png
 

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KRT
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Wow... So does that mean the plug's too hot, or mixture is too lean?
And if it's a "lean" condition, could it be caused by a stock ECU, not "mapping" properly for the mods that were performed (it sounds like a LOT was done). I wonder what mods were performed... Is the compression higher?
I ask 'cause I just bought a Kitaco hi-comp piston/hi-lift cam, but haven't installed, yet...
Good luck with your problem - it'll be interesting to follow...
 

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I wonder what mods were performed... Is the compression higher?
.
 

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Before I read anything the first thing that occured to me was WOW that's a white plug. Way too lean in there.
Wow... So does that mean the plug's too hot, or mixture is too lean?
And if it's a "lean" condition, could it be caused by a stock ECU, not "mapping" properly for the mods that were performed (it sounds like a LOT was done). I wonder what mods were performed... Is the compression higher?
I ask 'cause I just bought a Kitaco hi-comp piston/hi-lift cam, but haven't installed, yet...
Good luck with your problem - it'll be interesting to follow...
Mixture is too lean.
100% caused by the mods. Not "caused by the ECU". The ECU will never do that to a stock engine.
You need a fuel controller and wideband O2 big time. Start with +20% across the board and see what it does, but your mapping is totally [email protected]#ed.
 

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Mate first thing I would be doing is taking the head off the engine and check the piston.
If the plug looks like that what’s the condition of the piston yikes!
 

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Discussion Starter #8
Why do i see a .... 9Y ?

Do you have the right plug in it ...

View attachment 25930
Thats probably where I went wrong, going with and Autolite $2 plug rather then whats recommended NGK. I bought a new NGK plug and it fired right back up, I haven't took it for a test right yet. So ill have to get back to you on if my problem got fixed.
 

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Discussion Starter #9
Wow... So does that mean the plug's too hot, or mixture is too lean?
And if it's a "lean" condition, could it be caused by a stock ECU, not "mapping" properly for the mods that were performed (it sounds like a LOT was done). I wonder what mods were performed... Is the compression higher?
I ask 'cause I just bought a Kitaco hi-comp piston/hi-lift cam, but haven't installed, yet...
Good luck with your problem - it'll be interesting to follow...
My problem accord after I did the 55mm stroker crankshaft, new piston rings, and clutch plates. But I believe it was because of the cheaper spark plug i put in at the time.
 

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My problem accord after I did the 55mm stroker crankshaft, new piston rings, and clutch plates. But I believe it was because of the cheaper spark plug i put in at the time.
According to "Kawasaki Brad", you need a different O2 sensor and "controller"... I've been recommended the "A-racer" stuff by the good folks at "Steady Garage" - but I think we're talking about $500 or more...!
I'm still interested in what you can "get away with" with the stock ECU...
So, I hope simply changing the spark plug works for you!
 

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Discussion Starter #11
According to "Kawasaki Brad", you need a different O2 sensor and "controller"... I've been recommended the "A-racer" stuff by the good folks at "Steady Garage" - but I think we're talking about $500 or more...!
I'm still interested in what you can "get away with" with the stock ECU...
So, I hope simply changing the spark plug works for you!
I have a Hoedar
According to "Kawasaki Brad", you need a different O2 sensor and "controller"... I've been recommended the "A-racer" stuff by the good folks at "Steady Garage" - but I think we're talking about $500 or more...!
I'm still interested in what you can "get away with" with the stock ECU...
So, I hope simply changing the spark plug works for you!
[/QUOT
According to "Kawasaki Brad", you need a different O2 sensor and "controller"... I've been recommended the "A-racer" stuff by the good folks at "Steady Garage" - but I think we're talking about $500 or more...!
I'm still interested in what you can "get away with" with the stock ECU...
So, I hope simply changing the spark plug works for you!
My bike came with a Hoedar ecu and I was able to talk to the guy who tuned it. According to him everything seem ok. I'll look into changing the O2 sensor soon.
 

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KRT
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Ah, so you already have a non-stock ECU...
I guess I need to keep asking.
I received my Kitaco piston/ cam kit, but now I'm afraid to install it! I've only put a pipe (SP Tadao loop megaphone) on my bike, so far, and it's been running smoothly and consistently with the stock ECU.
What I don't understand is, since even the stock ECU is responding to various sensors, why wouldn't it simply make whatever adjustments are needed - no matter how you modify your bike?
So, did replacing the spark plug fix your bike?
 

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I guess I need to keep asking.
What I don't understand is, since even the stock ECU is responding to various sensors, why wouldn't it simply make whatever adjustments are needed - no matter how you modify your bike?
Scroll down to Bill Ramseyer Jr. / Quote from Facebook
Intake and exhaust is simply too much for the ECU to compensate

To avoid going Off Topic, Start a new thread if you have more questions about your bike (y)
 

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Thanks for the tip, Kaw'ee, as well as the welcome!
Yeah, I'm just a little hesitant, being new to this forum... It's also the first forum I've ever joined - so I don't yet know "the routine"...!
I do want to post some photos from Japan, as per your encouragement - but, I seem to be having problems doing that from this smartphone... Next time I'm on a computer, I'll try again.
Great forum - thanks!
 
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