Ken O'Conner Racing.

blasterdemon7

I'm not winning.
Nov 19, 2009
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Delaware
He is an amazing great guy. His work is top notch along with his customer service. He has been a huge benefit to this forum with his informative videos and the willingness to help with any problem by way of forum or phone. I have not yet had any work done directly from him but he was still willing to talk to me on the phone and help me understand everthing I wanted to know. The think that stands out the most to me about him is that he cares about enjoyment of the hobby. He doesn't just look at you as a doller sign. I am running one of his redesigned heads that I bought from another member. All I can say is that it looked amazing. Wanted to just hang it on my wall to look at instead of installing it.lol. Thanks Ken for all the great help you have given us.
 
Stock head on the left and a O'Conner redesigned head on the right.
cbc442a0.jpg
 
I also think Ken is a great builder with the best customer service I have ever encountered. I would never speak badly about kens work but I do have to say his port work (though flawless) is not as aggressive as some of the other builders. I have a 3mil stroker with an aggressive trl port and milled head. (rest of mods in sig) my cousin has another companies port work on a stock stroke cylinder. He has a 30mm carb and bills pipe and that's it. he blows me out of the water. just no way around it. it is faster. Not knocking kens work. If you want a good reliable cylinder that makes good power go to ken. if you are trying to maximise your power to the fullest, I would go to one of the other builders.
 
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I also think Ken is a great builder with the best customer service I have ever encountered. I would never speak badly about kens work but I do have to say his port work (though flawless) is not as aggressive as some of the other builders. I have a 3mil stroker with an aggressive trl port and milled head. (rest of mods in sig) my cousin has another companies port work on a stock stroke cylinder. He has a 30mm carb and bills pipe and that's it. he blows me out of the water. just no way around it. it is faster. Not knocking kens work. If you want a good reliable cylinder that makes good power go to ken. if you are trying to maximise your power to the fullest, I would go to one of the other builders.

So your sayin, your cousin can out ride you!

Any of the builders can build a motor as agressive as the next guy, if you explain how you want it done!

Don't forget motor work is only part of it, the rest is up to the rider and tune person!
 
I also think Ken is a great builder with the best customer service I have ever encountered. I would never speak badly about kens work but I do have to say his port work (though flawless) is not as aggressive as some of the other builders. I have a 3mil stroker with an aggressive trl port and milled head. (rest of mods in sig) my cousin has another companies port work on a stock stroke cylinder. He has a 30mm carb and bills pipe and that's it. he blows me out of the water. just no way around it. it is faster. Not knocking kens work. If you want a good reliable cylinder that makes good power go to ken. if you are trying to maximise your power to the fullest, I would go to one of the other builders.


i've yet to experience this in the trails, against other builders work,
ask anyone who's been to one of my rides if my KOR porting was slow,
better yet, ask my 3 buddies ...kfx700, rappy700, rappy 660
who routinely get their asses handed to them in the trails
anyone can build a "all top end, open feild motor"
ken gave me power everywhere, and i wouldnt have it any other way
 
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knew this was comin. you two are just so wrapped up over ken you can't let someone have an opinion. and No my cousin can't out ride me. we have both ridden each others quad while racing and his wins everytime. on the trails i will leave him bc I have better suspention and an all round better handleing quad. so now you guys can start arguing semantics about how my tuning is off. I built both of these quads and go the same help tuning them both. I have done everything the right way and they are both tuned to a T. It is apples vs apples here and the one apple beats the other one. that is all there is to it. And I love ken as much as the next guy!

But none of this will be taken into consideration and I will be attacked and shuned by some but f*ck it I am just giving my personal expirence with two topends
 
I started this thread and people have a right to post there opinion in a respectful way. There will be no bashing over it or I will close this thread.
 
Hey Scott, there's no way ur cousins should be faster with ur mods. Something isnt right,,port timing, jetting, gearing, timing, ken had a bad day... gotta be something. I had 4 other builders do cylinders plus Ken and his was the fastest for mx untill I got the ct. I would get ahold of him and see if u can figure it out.. he's got my 4 stroke motor right now and I gaurantee he wouldn't if he couldn't make power. Things dont always gel for whatever reason...just need to find what it is. Good Luck
 
knew this was comin. you two are just so wrapped up over ken you can't let someone have an opinion. and No my cousin can't out ride me. we have both ridden each others quad while racing and his wins everytime. on the trails i will leave him bc I have better suspention and an all round better handleing quad. so now you guys can start arguing semantics about how my tuning is off. I built both of these quads and go the same help tuning them both. I have done everything the right way and they are both tuned to a T. It is apples vs apples here and the one apple beats the other one. that is all there is to it. And I love ken as much as the next guy!

But none of this will be taken into consideration and I will be attacked and shuned by some but f**ck it I am just giving my personal expirence with two topends

Your opinion counts bro, but this thread is for Ken Oconner Racing, not any other builders work.
I have to agree with KG, , just a ported stock motor and pipe is not going to out run your quad with all the mods listed -don't care who did the work.

I apologize if i started a war!

Now to my review-

Had Ken, stroke, port/match my motor, couldn't be happier! Excellent workmanship and service. Awsome Builder with tons of Knowledge!
KOR!
 
This is why we stopped doing strokers unless we have the entire engine. I'm all for you guys saving money but I don't have a crystal ball. Vito's +3 crankshafts and connecting rods vary in stroke and length by as much as -.020 and +.040. This is a fact I won't even argue about. Even if we don't consider all of the other compounding tolerances in the engine, .060 is a huge variable. With that in mind, we have to consider the longest possible geometry when we approach the cylinder and head when we don't have the cases and the crank that the cylinder will be mated to. Scott did his own lower end. I never saw it and he knew there were variables involved. We ported his cylinder and did his head mod. His compression was later corrected by further modifying the head. Slick, Awk and Gibson all sent entire engines to the shop. We had all of the pieces of the puzzle to work with.
 
Ken's right... I get this problem at work all the time. A customer will bring in a carburetor off their riding mower which needs rebuilt, and I do the work, but sometimes the customer comes back later wondering why the fresh carb didn't fix their problem. 9 times out of 10 the carb is either not adjusted properly (you can only get them close on the bench), or the owner didn't properly clean the fuel tank and lines and now the fresh carburetor is full of bad gas again!

Having the whole package in front of you just makes life SO much easier for a mechanic or engine builder. With it all right in front of you, you can be sure the work gets done 100%.

BTW, I'm very happy with my KOR-built engine. Its not a stroker, but still absolutely rips and makes bigger quads think twice before racing me more than once. :D
 
This is why we stopped doing strokers unless we have the entire engine. I'm all for you guys saving money but I don't have a crystal ball. Vito's +3 crankshafts and connecting rods vary in stroke and length by as much as -.020 and +.040. This is a fact I won't even argue about. Even if we don't consider all of the other compounding tolerances in the engine, .060 is a huge variable. With that in mind, we have to consider the longest possible geometry when we approach the cylinder and head when we don't have the cases and the crank that the cylinder will be mated to. Scott did his own lower end. I never saw it and he knew there were variables involved. We ported his cylinder and did his head mod. His compression was later corrected by further modifying the head. Slick, Awk and Gibson all sent entire engines to the shop. We had all of the pieces of the puzzle to work with.

That is exactly what I was thinkin ken. If you remember my squish was over twice what it should have been when I origionally bolted it up. Is this fixable? or is the cylinder shot? I think you said my crank was the shortest extreme of the vitos tollerances.
 
Ken's right... I get this problem at work all the time. A customer will bring in a carburetor off their riding mower which needs rebuilt, and I do the work, but sometimes the customer comes back later wondering why the fresh carb didn't fix their problem. 9 times out of 10 the carb is either not adjusted properly (you can only get them close on the bench), or the owner didn't properly clean the fuel tank and lines and now the fresh carburetor is full of bad gas again!

Having the whole package in front of you just makes life SO much easier for a mechanic or engine builder. With it all right in front of you, you can be sure the work gets done 100%.

BTW, I'm very happy with my KOR-built engine. Its not a stroker, but still absolutely rips and makes bigger quads think twice before racing me more than once. :D

your quad was faster than mine too. brapp. I don't think you ever got to ride mine though.
 
That is exactly what I was thinkin ken. If you remember my squish was over twice what it should have been when I origionally bolted it up. Is this fixable? or is the cylinder shot? I think you said my crank was the shortest extreme of the vitos tollerances.

He should be able to shave the head a bit to tighten up the squish.