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Discussion Starter · #1 ·
Both bikes have modded stock exhaust and modded air box. Both jetted properly. This just showed the difference between the two. Pretty big difference. Its cool to see. They both are fast in their own way. Ill keep my sx. LOL

 

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That is pretty cool, the XC has more low end and the SX has more top. seems like KTM did there homework with those engines.
 

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it's the big bottom end torque I like on the RFS engine that's missing from the SX engine...........

up to 7 k the xc has a strong advantage ?? or am I reading this wrong
 

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Discussion Starter · #4 ·
it's the big bottom end torque I like on the RFS engine that's missing from the SX engine...........

up to 7 k the xc has a strong advantage ?? or am I reading this wrong

Im sure ranch would be glad to trade ya. Im guessing adjusting those cams around will help the bottom end. Im totally happy with mine. I raced it last night for the first time. I was soooooo amazed at how fast it was for only 51whp. Literally feels faster than a ltr with 55whp. Its crazy. Im completely happy with the power. If I didnt want to test part for you guys Id probably just put exhaust on it and leave it. But the quest for power has begun. First thing exhaust and then off to conquer the intake system. I hate the filter design. Box is nice but thats it.

We also tested the sx intake on the xc tonight. Ill let Ranch post those results.
 

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do you guys have the comparision drag race software that dynojet used to have on their older software: allowed you to race off two different dyno curves ??? (assuming all other variables where identical).

Intake : THAT will be interesting see..........

the bike guys report 1 hp+ by getting rid of the backfire screen and running the special flame proof twin airfilters on the 2 wheelers. K&N may even be a bit better again. I'm betting that an inline K&N filter (no 90 degree bend) will flow +2 hp over the stock setup. Maybe the Raptor GYTR filter (with the flat top rather than circular) will be a good option ? The high shock mount is gonna be the bug bear in a straight shot setup ?

Craig
 

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Discussion Starter · #7 ·
Soon as Brad gets his we will dyno it. Should be within a few weeks.
 

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And that will be in the next couple weeks kids:)
Stay tuned to watch a 450 have more power than a 505 lol...I wish
 

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I have read the same thing. They supposedly have the exact same peak hp. The difference is how the 450 gets it there. They say it is way more expolosive off of the bottom and just rips it to the top, where the 505 is more of a smooth linear power curve. We will see though when the dyno's start pulling both of them.

Brian
 

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Discussion Starter · #11 ·
I have read the same thing. They supposedly have the exact same peak hp. The difference is how the 450 gets it there. They say it is way more expolosive off of the bottom and just rips it to the top, where the 505 is more of a smooth linear power curve. We will see though when the dyno's start pulling both of them.

Brian
There is no way. The 477 will have more power across the board. Im willing to bet from my experience that the curve will be identical just about 1-1.5whp less on the 450. Any takers on my bet?? LOL
 

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Well my web cams and cp piston should put it over your! :eek:

jk, baby steps ;)
 

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i hoping the SX 546 stroker BB will haul the mail...............
 

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525 xc main jet is 155. What needle and clip position ? pilot jet ?
at that time it had a 42 pilot with the needle on the 3rd down
a 45 pilot would have been better
 

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Both bikes have modded stock exhaust and modded air box. Both jetted properly. This just showed the difference between the two. Pretty big difference. Its cool to see. They both are fast in their own way. Ill keep my sx. LOL
MY 570 XC can take your SX Anthony....in reverse... :lol: :lol: :lol:
 

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Discussion Starter · #18 ·
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