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Solutions for MtnHorse lust for more power...

tomk

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Oct 16, 2008
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cr500,

how do you think the bike will run at low speeds/rpm. I have heard that the big four strokes have such a spurratic exhaust impulse that when turbo'd they run like crazy at high rpm but are kind of doggy and inconsistent at low rpm. I would love to do this but am a little weary from what I have read.
 

cr500afx

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Dec 18, 2008
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Good question. Best answered by Kelly at KMS Performance.
But from me, I had the same concerns and did some research and found KMS. Kelly has been turboing (is that a word?) single cylinder four strokes for years and has it pretty figured out after lots and lots trial and error and many, many dyno runs. His similar dyno runs (ATV 450's) show a nice linear HP curve. He is very specific on tube lengths, turbo-sizing, and fuel mapping to make it work. You'll note how close the turbo is to the exhaust port on my install. This is a "must" per Kelly. Also the fuel mapping is very critical and KMS has their own programming for the fuel based on experience and then it is dialed in during the dyno runs for max safe HP. I'll post the dyno runs as soon as they're available.
I'm keeping my fingers crossed......
 
T

turbo99

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Mar 16, 2008
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tacoma,wa
Good question. Best answered by Kelly at KMS Performance.
But from me, I had the same concerns and did some research and found KMS. Kelly has been turboing (is that a word?) single cylinder four strokes for years and has it pretty figured out after lots and lots trial and error and many, many dyno runs. His similar dyno runs (ATV 450's) show a nice linear HP curve. He is very specific on tube lengths, turbo-sizing, and fuel mapping to make it work. You'll note how close the turbo is to the exhaust port on my install. This is a "must" per Kelly. Also the fuel mapping is very critical and KMS has their own programming for the fuel based on experience and then it is dialed in during the dyno runs for max safe HP. I'll post the dyno runs as soon as they're available.
I'm keeping my fingers crossed......

how much boost are you going to run?
 

Jon Mutiger

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Oct 20, 2010
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Maple Ridge, BC
I'm really interested to see what a longer track version on a sport bike is like to ride.. I can't see the riding position being much fun, so I think the ideal way to deal with that would be to shoe horn a big displacement I-4 into a dirt bike chassis.. But that simply won't fit very nicely.

It's going to be interesting to see what variations of a snow bike come out of this whole quest for the ultimate machine.

Jon
 

Matte Murder

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I've been thinking about a mountain horse too. One thing holding me back is the gearbox on the bikes and the relative lack of power. I sure like the way the clutches work on snow mobiles and 165hp would be a lot of fun. Would it be possible(anything is possible I guess but possible for not a ridiculous amount of money) for somebody to put an 800 ETEC into some kind of bike frame and set it up as a snow bike?
 
T

tfrick821

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Nov 27, 2007
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eastern ia
I've been thinking about a mountain horse too. One thing holding me back is the gearbox on the bikes and the relative lack of power. I sure like the way the clutches work on snow mobiles and 165hp would be a lot of fun. Would it be possible(anything is possible I guess but possible for not a ridiculous amount of money) for somebody to put an 800 ETEC into some kind of bike frame and set it up as a snow bike?

I think they did already it was called the snowhawk?
 

cr500afx

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Dec 18, 2008
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is it going to be reliable at 14lbs?

I hope so. The 550 motor is apart getting rebuilt with all heavy duty stuff.
The Honda TRX ATV's that KMS has similarly built stay together.
But, only time will tell.....
 
S
Nov 20, 2010
30
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please hurry and test 750

Im waiting for someone to build and test a mountain horse with a gsxr 1000 motor as a have one in my garage that noone will buy. If a 450 works think about a turbo gsxr 1000. Might not need my turbo m1000 anymore. Any one try a bigger track yet. Wow, might be the end of my snowmobiling. Please let me know how that 750 works.
 
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turbo99

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Mar 16, 2008
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tacoma,wa
Im waiting for someone to build and test a mountain horse with a gsxr 1000 motor as a have one in my garage that noone will buy. If a 450 works think about a turbo gsxr 1000. Might not need my turbo m1000 anymore. Any one try a bigger track yet. Wow, might be the end of my snowmobiling. Please let me know how that 750 works.

im running it in the Enumclaw Washington grass drags this weekend
 

Timbersled

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Apr 22, 2008
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Awesome!

I can't wait to hear how it goes. Allen and Derick proved that these are not just "snow" bikes this weekend at the Big Nasty hill climb. I am sure you will do the same. Someone even came up to Allen at the Big Nasty and said "hey that looks like it might go well in the snow too!" :face-icon-small-con

posted by Dave @ Timbersled
 

cr500afx

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Dec 18, 2008
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Turbo CRF 450R Update

Pics of exhaust. First dyno run last night @ 74HP with 4PSI boost.

RH side exhaust no plastic.jpg RH side with exhaust 1.jpg RH side with exhaust 2.jpg Top - Tank View exhaust.jpg Exhaust - Frame Clearance.jpg Turbo exhaust outlet.jpg Turbo CRF450 dyno #1.jpg SCOTT TURBO HP 4PSI.jpg
 
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