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Discussion Starter · #1 ·
i was looking around for an aftermarket or cheater head for my 2006 rev 800. i contacted rk tek and they were claiming a big 10hp out of a cheater head on pump gas. im wondering if anyone has this head (cheater or rk tek head)and what they think about there "10hp gain."
 

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I have not dynoed the rk tek head on an otherwise stock machine. On my old 2002 mxz 600 with RKT head, when I got it dialed in (had to drop 5 main jet sizes) it required more pin weight to be added, so, it did make more power, how much I don't know for sure, but I never lost a race to my buddies who had polaris xc 600's back in the day in a 1/4 mile on snow. This was all informal trail sleds lining up, not sanctioned racing. Before the jetting was correct, it did not run well, about like stock.

PS. Before anyone thinks the motor was leaned out to make more power, nope. Jetting was safe down to -20F and I ride at about 800 ft above sea level, egt's were around 1125-1150 range WOT and I could hold it WOT for a couple miles with no worries. With any of these heads, try to follow the setup guidance (assuming an otherwise stock motor) and if you add pin weight to keep RPM's at target RPM, your adding power, all else being equal.
 

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whats m-tech?
I might be wrong but m-tech was designed by a former brp race tech, i know Sylvain Laflamme sells them, his site is on here look for Laflamme racing, biggest gain from any head is the ability to disperse heat,
 

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I might be wrong but m-tech was designed by a former brp race tech, i know Sylvain Laflamme sells them, his site is on here look for Laflamme racing, biggest gain from any head is the ability to disperse heat,
they dont make them anymore skidoo put a stop to it because it was the best thing going i have a brand new one sitting downstairs waiting to go on soon lucked out finding it
 

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I might be wrong but m-tech was designed by a former brp race tech, i know Sylvain Laflamme sells them, his site is on here look for Laflamme racing, biggest gain from any head is the ability to disperse heat,
That is absolutely correct, that and its ability to burn fuel.

I run Kelsey's cheater head in both my trail sled along with his 827BB kit. I also run his cheater head in my mountain sled with Big John's 840BB kit.

These heads have stepped back side heads. It give it more surface area to transfer heat. It also has interior design to swirl the fuel to better mix in a shorter amount of time. The combination of swirl technology and heat transfer make a fantastic head to run.

Here are the pictures of his head as you will get them.



Here is the inside of the domes for the chamber. It has ridges machined into the domes.



Here is the heat transfer side of the head. You can see the steps that increases the surface area to disperse heat better.



Here you can see the expert machine to make it all fit like a glove.





Here is the outside....no one expects anything other than stock.......Moooo-ah-ha-ha-ha-ha-haaaaaa

 

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I'm running Kelsey's drop in kit in my 05 800ho. I have about 3000 miles on his kit and there are no problems and it runs extremely strong. Once you get the jetting correct, it will run strong. Add EGT's to over come the lean fear and you'll find it wakes up the 800. Then get your clutching right and hang on. I'm not running the cheater head, but have the 13.5 domes with his head. I also remapped the ECM. Maize, I spoke to Kelsey today about doing the 827 and I was curious if you also did the porting? My cylinder are still in real good shape, so I may stay with the 800 for now but get the cylinders ported.
 

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I'm running Kelsey's drop in kit in my 05 800ho. I have about 3000 miles on his kit and there are no problems and it runs extremely strong. Once you get the jetting correct, it will run strong. Add EGT's to over come the lean fear and you'll find it wakes up the 800. Then get your clutching right and hang on. I'm not running the cheater head, but have the 13.5 domes with his head. I also remapped the ECM. Maize, I spoke to Kelsey today about doing the 827 and I was curious if you also did the porting? My cylinder are still in real good shape, so I may stay with the 800 for now but get the cylinders ported.
YUP. I had him do the port work on the cylinders, too. I am still waiting for my dyno to get his dyno fixed.
 

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Discussion Starter · #11 ·
they dont make them anymore skidoo put a stop to it because it was the best thing going i have a brand new one sitting downstairs waiting to go on soon lucked out finding it
wanna sell it?


does any company copy the design that m-tech had?? i really want one of those heads now
 

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they are dreaming the only head out there that even comes close to that is the m tech and thats 5 to 7
May I see proof of every dyno session you went to, dyno-ing "EVERY head out there" ?

Huh big guy? Awfully bold statement you brought to the table...back it up.

Can't wait to see the come back for this one!!!!!
 

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What percentage of the market actually buys this product?
Who else has noticed substantial improvements and where were the compromises. Being a mechanical engineer I don't believe repackaged(or passed on) advertising info, and theories that have product marketing spins on them. Even passing on thermodynamic claims from those who do not even understand the subject is misleading to the rest of us.

I'm in the market for a head and would like to get actual third party comparison info if anyone has any.

Some good info for a start. Let's keep it going with real stuff and testimonials. Any down sides to the head ie warpage etc.
 

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What percentage of the market actually buys this product?
Who else has noticed substantial improvements and where were the compromises. Being a mechanical engineer I don't believe repackaged(or passed on) advertising info, and theories that have product marketing spins on them. Even passing on thermodynamic claims from those who do not even understand the subject is misleading to the rest of us.

I'm in the market for a head and would like to get actual third party comparison info if anyone has any.

Some good info for a start. Let's keep it going with real stuff and testimonials. Any down sides to the head ie warpage etc.
What do you mean by , "Even passing on thermodynamic claims from those who do not even understand the subject is misleading to the rest of us."?

I hope you weren't referring to the stepped head design. By using a stepped head, instead of a smooth side, it pretty much doubles the suface area for heat to disipate, and coolant to flow over. (by using Pythagorean's Theorem, if the long side is 5, then the right angle side is 3 and 4 for a total area of 7. Take 5 from 7 and you get 2. 2/5 is 40%. Then take into account that the steps are radius'd and you may not be actually 2x's the amount, but you have AT LEAST 60% more area than a standard straight sided dome.) It gives more suface area for the coolant to flow over to keep it cooler. With the machined inner part of the outside shell of the head being larger, it allows more coolant in the head which also aids in heat disipation.

I have had no head warpage, or even heard of any of RK Tech heads warp. I am an engine builder/modifier. Big John is an engine builder/modifier. There are several other companies that build/modify engines and all use Kelsey's stuff. That isn't by accident.

There is even a company in Canada that is copying his stuff.

The M-Tech stuff was good, but my guess as to why they went out is more of a cost issue, than BRP making them. The material they were made from was VERY expensive, and their prices reflected that. I believe their margins were too low and didn't move enough product. BRP would have no control over aftermarket products.

If there is a downside, I haven't found it. Big John hasn't found it. It is not hype. Kelsey's product is good and proven. That is why I chose to use it. I design sleds, I don't just build them. I make them better, not just flashy.

I haven't put the numbers, or did stock vs non-stock dyno runs myself. But Kelsey has the numbers. I believe his number, and here is why. I did an 827BB kit with him a while back. I asked him if he wanted me to send him the dyno numbers before I posted them. He said no need, he knew what his engine would pull and wasn't afraid that my numbers would not duplicate what he published. He just said to do the runs and post them, they will be similar to what is on his site.

My dyno guys machine is broken down at the moment. Within the next couple of weeks (hopefully) will be able to dyno my sleds and get then dialed in with real HP numbers.
 

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MAIZE583

This was not ment to be a slam against you. In fact the opposite. I'm looking for feedback from those, like yourself, who have worked with the product and don't just pass on marketing hype because of manufacturer loyalty. Your information is well received. However there are other folks out there do like to claim expertise assess how good a product is who don't even use it. This sends out wrong signals to the rest of us. Real word testimonials is where it's at. As the saying goes "If it works in the real world, then go back to invent a theory for it."

I'm a trail sledder to likes to get on it when on lakes, but I need reliability and don't have the time (er down time during the season) to find out about the modification that didn't work out well.

I can respect all the information you provided.

Tom

What do you mean by , "Even passing on thermodynamic claims from those who do not even understand the subject is misleading to the rest of us."?

I hope you weren't referring to the stepped head design. By using a stepped head, instead of a smooth side, it pretty much doubles the suface area for heat to disipate, and coolant to flow over. It gives more suface area for the coolant to flow over to keep it cooler. With the machined inner part of the outside shell of the head being larger, it allows more coolant in the head which also aids in heat disipation.

I have had no head warpage, or even heard of any of RK Tech heads warp. I am an engine builder/modifier. Big John is an engine builder/modifier. There are several other companies that build/modify engines and all use Kelsey's stuff. That isn't by accident.

There is even a company in Canada that is copying his stuff.

The M-Tech stuff was good, but my guess as to why they went out is more of a cost issue, than BRP making them. The material they were made from was VERY expensive, and their prices reflected that. I believe their margins were too low and didn't move enough product. BRP would have no control over aftermarket products.

If there is a downside, I haven't found it. Big John hasn't found it. It is not hype. Kelsey's product is good and proven. That is why I chose to use it. I design sleds, I don't just build them. I make them better, not just flashy.

I haven't put the numbers, or did stock vs non-stock dyno runs myself. But Kelsey has the numbers. I believe his number, and here is why. I did an 827BB kit with him a while back. I asked him if he wanted me to send him the dyno numbers before I posted them. He said no need, he knew what his engine would pull and wasn't afraid that my numbers would not duplicate what he published. He just said to do the runs and post them, they will be similar to what is on his site.

My dyno guys machine is broken down at the moment. Within the next couple of weeks (hopefully) will be able to dyno my sleds and get then dialed in with real HP numbers.
 

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i love the lack of knowledge in these rooms people jump all over peoples "edit for bad language" just to get attention ya this is for you big guy i have read so many posts about bad gas, brp suxs and how someone else screwed up when they have a meltdown plain and simple if you don't know what you are doing leave it alone i am not saying anyones head is better then the next as we all know it all depends what else is done or is going to be done the best bang for the buck stock was the m tech hands down there is no head out there that will increase hp 10+ thats horse poo you wanna put a thinner base gasket on there you might get close but like i said thats not stock
 

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i love the lack of knowledge in these rooms people jump all over peoples "edit for bad language" just to get attention ya this is for you big guy i have read so many posts about bad gas, brp suxs and how someone else screwed up when they have a meltdown plain and simple if you don't know what you are doing leave it alone i am not saying anyones head is better then the next as we all know it all depends what else is done or is going to be done the best bang for the buck stock was the m tech hands down there is no head out there that will increase hp 10+ thats horse poo you wanna put a thinner base gasket on there you might get close but like i said thats not stock
thats a great rebuttal.


Again, do you have dyno proof? Perhaps youre the one with the lack of knowledge
 

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MAIZE583

This was not ment to be a slam against you. In fact the opposite. I'm looking for feedback from those, like yourself, who have worked with the product and don't just pass on marketing hype because of manufacturer loyalty. Your information is well received. However there are other folks out there do like to claim expertise assess how good a product is who don't even use it. This sends out wrong signals to the rest of us. Real word testimonials is where it's at. As the saying goes "If it works in the real world, then go back to invent a theory for it."

I'm a trail sledder to likes to get on it when on lakes, but I need reliability and don't have the time (er down time during the season) to find out about the modification that didn't work out well.

I can respect all the information you provided.

Tom
No worries at all here. I feel you can't really go wrong with any of the "Big Name" heads. They all have similar advantages. They all do the same thing, pull heat from the heat from the chamber and compress gases.

I would stay away from one-off companies that only make claims against other compaines. Just stay with companies that will tell you what they can do for you, NOT what they do against someone else.

If you stick with companies that are worried about you, and not what someone else is doing. You will have a good experience, and a good product. Companies that feel that they need to put other companies' products down won't treat you like you should be treated. To me that just shows you a lack of confidence in their ability to get you a great product.

That is the way I do business, and I prefer to do business with companies that do their business in a similar fashion. That is another reason I do business with Kelsey. His products are top notch, and he isn't worried about other people's stuff. He knows his products, and he treats customer's VERY well.

I hope this helps.....LOL
 

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dyno proof are you serious dude for real come on thats like livingstons (cat dealer) racing all new cats against doos and beating them all of corse they will beat them why would a cat dealer let a doo beat his cat and of corse they are all stock lmao what a joke just like dynos a dyno is nothing but a baseline to work off of means nothing out on the lake or trail that 200 hp on the dyno could be 180 on the lake or could be 220 who knows all i can tell you is m tech was the best head out and people know it thats why they pay more for them used then new heads form other people
 
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