The new HO makes almost 20 more HP as do the Doo and Suzuki 800. More cc's and better porting should be able to do +30.
Polaris rmk 858 rk tek on the dyno
- Thread starter FinRmk
- Start date
The new HO makes almost 20 more HP as do the Doo and Suzuki 800. More cc's and better porting should be able to do +30.
There is something wrong with the tune. Sure looks like it pulled timing, probably the wrong fuel for 13:1 at sea level. Regardless it should be pretty obvious something went wrong on that run. A kit designed to run to 8500 doesn't fall on its face at 8000 unless something is wrong.
No skin in the game here. Just a keyboard racer, but I tend to lean this way as well ^^^^^^^^^.
Also, run the 14.1 heads with proper fueling and dyno it again.
Imho, the kit with 14.1 heads, gearing, and clutching, at elevation probably feels/behaves/butt dynoes/clutches like its "got an xtra 30 hp"
Also, run the 14.1 heads with proper fueling and dyno it again.
Imho, the kit with 14.1 heads, gearing, and clutching, at elevation probably feels/behaves/butt dynoes/clutches like its "got an xtra 30 hp"
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Seems pointless without a stock motor baseline on the same dyno. Maybe your stock motor would have made 130. Not likely, but just maybe.
"Better porting"
That may be part of the issue.
Besides that.
Its no secret what rktek does with lowered port timing.
Its an old trick that makes a sled go from 80% good days to 50% good days depending on conditions. IE
Snow density
Air density
Altitude
Temperature
The peaky powerband comes off optimum so easy that clutching is a constant endeavor.
That 50% may be better than the best of the 80% but you also have to suffer the 50% off days.
Lowered port timing works better at high altitude.
Or so i hear.
I've been around a few rktek motors and have yet to see one run as good as the promise.
"Many happy customers"
"No reported issues"
LOL Same excuses different decade.
This thread needed pictures.
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A little 858 action shot!
Here is a dyno chart of stock vs Rk Tek 858 here in Norway, at sea level. Not my sled, but almost the same setup:
Pro Rmk 800, RkTek 858 v2 kit, bigger y-pipe, SLP air intakes and advanced timing of 1.5degrees.
I have just installed my 858 kit and is halfway of breaking in the enginge. Actually i dont need to dyno it to be happy, the power gain this engine produces is well enough for me to be happy with my purchase.
I would be really surprised if this kit only produced 15hp, by the feel of the pull and torque this now have gotten.
I have rode turbo pro's for the last two years, and tought this big bore kit was going to dissapoint me, but im actually surprised.
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"Better porting"
That may be part of the issue.
Besides that.
Its no secret what rktek does with lowered port timing.
Its an old trick that makes a sled go from 80% good days to 50% good days depending on conditions. IE
Snow density
Air density
Altitude
Temperature
The peaky powerband comes off optimum so easy that clutching is a constant endeavor.
That 50% may be better than the best of the 80% but you also have to suffer the 50% off days.
Lowered port timing works better at high altitude.
Or so i hear.
I've been around a few rktek motors and have yet to see one run as good as the promise.
"Many happy customers"
"No reported issues"
LOL Same excuses different decade.
This thread needed pictures.
I dont think there is less duration on the drop in and 858 kits.
Why is this dyno sheet even being discussed when it quits at 8000rpm and advertised peak power is at 8500rpm... there is obviously something wrong with either the dyno or the sled.
Kanedog your argument is flawed, nobody ever stated the 858 was gonna produce an extra 30hp at 8000rpm... Kelsey has advertised a solid 25hp gain at 8500rpm compared to stock motor at 8200rpm...
Kanedog your argument is flawed, nobody ever stated the 858 was gonna produce an extra 30hp at 8000rpm... Kelsey has advertised a solid 25hp gain at 8500rpm compared to stock motor at 8200rpm...
His "patented head design " is inset into the cylinder and uses a shorter piston.
The rev 2 kit adjusts the piston size to match the shim.
It has the same duration but the ports are closer to the head.
This is why higher rpm produces the hp "peak".
I think he uses Worsner pistons in his kit and it seems like everything takes longer to break in and take a set with them. Last year I had a Bikeman 940 in a cat and I thought it was running pretty good and at the 240 mile mark it was like I added another 25 hp to it some how. It was a very noticeable difference. Just a thought, hope it eases a little pain.
your wrong. the patent refers to the shape of the combustion camber. as to kanedog that dyno sheet sure looks like 30 hp to me. unless he's a liar to.
The dyno goes to 8300 not 8000 which is good enough for me.
Dyno sheet is manipulated. Notice how the stock hp is 139?
How can that be when factory and all other dyno sheets show 140-145? Cmmmmmm. Padding the numbers in favour of a hop up? Yep.
Notice how the new run is EXACTLY 169? Magically the claimed gain is 30HP?
Notice how there is no info AT ALL about the correction factor on both dyno runs?
Notice how the stock dyno looks like it is drawn in there where as the aftermarket has dips and valleys?
Lemme guess, the dyno was from someone who sells the kit? Surprise surprise.
Im simply saying that the promise was 30hp. Even at 25hp, thats a lie. Flat out. Yea, it's a nice power gain, just not what the seller says it is.
If you butt dyno gurus wanna defend shady business practices, bait and switch etc, go ahead. I have no horse in this race. Buy all the kits ya want. Nut swing away.
Dyno sheet is manipulated. Notice how the stock hp is 139?
How can that be when factory and all other dyno sheets show 140-145? Cmmmmmm. Padding the numbers in favour of a hop up? Yep.
Notice how the new run is EXACTLY 169? Magically the claimed gain is 30HP?
Notice how there is no info AT ALL about the correction factor on both dyno runs?
Notice how the stock dyno looks like it is drawn in there where as the aftermarket has dips and valleys?
Lemme guess, the dyno was from someone who sells the kit? Surprise surprise.
Im simply saying that the promise was 30hp. Even at 25hp, thats a lie. Flat out. Yea, it's a nice power gain, just not what the seller says it is.
If you butt dyno gurus wanna defend shady business practices, bait and switch etc, go ahead. I have no horse in this race. Buy all the kits ya want. Nut swing away.
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I was referring to his combustion chamber shape, and that the shape of it, is inset into the cylinder.
So your saying the dyno has been manipulated so why are we even arguing about it, its obviously BS anyway? How can you call someone a liar over a BS dyno sheet?
The 858 falls on its face before 8000rpm how can that be accurate if peak power is 8500? Something happened or something isn't right period.
Dyno's are gay they can never be trusted
Butt dynoes cant be trusted either lol
All that matters is whos the first one on top of the hill. Any takers! ?
All that matters is whos the first one on top of the hill. Any takers! ?
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you may want to have yourself checked out by a really good mental health expert . it seems like you react this way a lot , the dyno numbers are great when it supports your point of view , but they are false ,manipulated , etc,etc. when they go against your b/s point of view toward all things rkt.
sorry I misunderstood
