KLX 250 ( 300 ) camshaft mod by Marcelino

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  #141  
Old 06-26-2011 | 02:35 AM
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Originally Posted by kansas-klx
ACR is only used during starting. It's to hold open an exhaust valve when rpm is below around 500 rpm (someone correct me if I'm wrong). Supposed to relieve stress on the starting system. Once the bike's running, and if the ACR isn't stuck engaged, it should not be a factor at all.
After thinking about it, and how the ach works, why does its position matter anyway? The bikes engine never stops and starts in the same spot...so what if its 10° off?
 
  #142  
Old 06-26-2011 | 03:12 AM
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Originally Posted by RayTard
After thinking about it, and how the ach works, why does its position matter anyway? The bikes engine never stops and starts in the same spot...so what if its 10° off?
Marcelino actually answers that question in the original post. Difficult for me to explain but he does a great job at it. Need to read it a couple of times, though, before it sinks in...
 
  #143  
Old 06-26-2011 | 03:44 AM
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I read somewhere on the net about hard starts with the 09 klx and Kawasaki recommended shaving .020 off the ACR to help with start up.
I wonder if shaving it would do the same as turning it 7 deg?

"The ACR in the KLX ( at least the new ones ) is EXACTLY AT THE LIMIT"
What end of the limit? Too much or too little?
 
  #144  
Old 06-26-2011 | 03:50 AM
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Well, I have read through this entire thread about 2 times now and I will admit I'm still not fully understanding. Does this free mod add any HP. If so how much is it adding to the "what every one claims is 18hp stock".
 
  #145  
Old 06-26-2011 | 03:56 AM
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Originally Posted by 2007 Green Machine
Well, I have read through this entire thread about 2 times now and I will admit I'm still not fully understanding. Does this free mod add any HP. If so how much is it adding to the "what every one claims is 18hp stock".
I read this at the bottom of the very first post:
Ladies and gentlemen ( and those who aren´t sure ) : WE HAVE 25 HORSIES ! .
And a big fat and flat layer of torque to go with it

so i think the gain is 25-18= 7hp gain????
 
  #146  
Old 06-26-2011 | 04:10 AM
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Originally Posted by bumblebee
I read somewhere on the net about hard starts with the 09 klx and Kawasaki recommended shaving .020 off the ACR to help with start up.
I wonder if shaving it would do the same as turning it 7 deg?

"The ACR in the KLX ( at least the new ones ) is EXACTLY AT THE LIMIT"
What end of the limit? Too much or too little?
Hey bumblebee,

From what I understand of Marcelino's post, when you retard the exhaust cam (opens a little later) the ACR also retards if not adjusted on the shaft. When the ACR retards (not adjusted for the shaft position change), that means that there is a little less compression available for starting. That's why he says to press it out and move it back the other way. Otherwise it will start cold like it was a worn engine and hardly start at all hot.

In fact, he moved it (ACR) a little bit further advanced of it's original degrees to compensate for anticipated wear over time. (Marcelino, correct me if I mis-understood your original post)

It's getting late for me so off to bed, now! Hope this all helps.
 
  #147  
Old 06-26-2011 | 04:10 AM
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Originally Posted by GaryC
I read this at the bottom of the very first post:
Ladies and gentlemen ( and those who aren´t sure ) : WE HAVE 25 HORSIES ! .
And a big fat and flat layer of torque to go with it

so i think the gain is 25-18= 7hp gain????
I read every thing so carefully, I have no idea how I could have missed that. I feel like a jackass now!
 
  #148  
Old 06-26-2011 | 05:18 AM
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It sounds like we have one positive review and two not so positive or neutral reviews. So is the jury still out on this one?
 
  #149  
Old 06-26-2011 | 05:47 AM
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Originally Posted by PTECH
It sounds like we have one positive review and two not so positive or neutral reviews. So is the jury still out on this one?
I did the mod for my 351. Everything felt really good in gears 1,2,3,6. Gears 4-6 were muddy. Not sure if it's a timing issue or jetting issue or what. Definitely picked up the low end though.
 
  #150  
Old 06-26-2011 | 07:42 AM
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How can you get results by moving only one cam??
 


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