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2012 KTM 300xcw power mods

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I just switched from a 05 450r to my new 300xcw. I love the new bike and it's low end power. It' feels so much lighter. 2t throttle is so much more fun than the 4t.

But it just doesent seem to have much mid to top end power. Can this be fixed with jetting. Or dose it need more work than that. Maybe a head mod like the SXS moded, or dicks racing carb bore. I don't want to loose the low end to gain more top end. I would just like to be able to have a stronger mid top end as well. Is this asking to much from a 300. And please I don't want it on race gas. I already have two other bikes on it. Did I say I love this bike.

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I would start with the simple, cheap stuff first. PV, jetting. You will be surprised at what you can gain from that. From what you are describing, sounds like it could use some dialing in of the jetting.

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Could be jetting. I'm running a 35 pilot and a 165 main at sea level. And am using N27J neddle in the 4th position. Temps are in the low 60s. I read that some use the RM250 neddles. I might have to try one. Thanks

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Lower your needle 1 or 2 clips and go up to a 38 pilot. Red pv spring flush will give you what your missing...

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I just put the sx head on my xc 300 on its almost to much power, had to unplug the mapping to tame it down a littlepring in it

put that red spring in it

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I have a 09 SX 250, added a 300 SXS kit, added a pipe, put a EXP Core in it, jetted it, regeared it, all trying to get the long pull of my 09 CRF 450. It has become a money pit for me. I went back to the 450.

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Update. I put the red spring in and am loving it. Now 2nd and 3rd gap is gone. You do get two much wheel spine in 1st and 2nd with the red spring. But I still like it better than the yellow spring. The power band is more linear. Have not tried the map switch yet. Will do that next to see if it helps with the wheel spin in 1st and 2nd.

And as far as the jetting go I got it pretty close Now I think. Thanks every one.

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I just switched from a 05 450r to my new 300xcw. I love the new bike and it's low end power. It' feels so much lighter. 2t throttle is so much more fun than the 4t.

But it just doesent seem to have much mid to top end power. Can this be fixed with jetting. Or dose it need more work than that. Maybe a head mod like the SXS moded, or dicks racing carb bore. I don't want to loose the low end to gain more top end. I would just like to be able to have a stronger mid top end as well. Is this asking to much from a 300. And please I don't want it on race gas. I already have two other bikes on it. Did I say I love this bike.

Get the head milled for bottom to mid for crazy pop. Set the PV toggle at flush and use the red spring. Get the carb bored for the top end and it will breathe fire.

Trey at Wildcat Motorsports does both with quick turnaround.

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I have an '07 and along with careful jetting (as it turns out, the KTM manual is just about dead on for jetting recommendations) the red PV spring, a Pro Circuit pipe (better than the FMF it replaced) and a shortened, stock silencer (minus 3") there was still a bit of a flat spot between the off-idle torque and the "hit".  I switched the base gasket for the thinnest available (.2MM) and milled .035" off the head and put in a fresh Wiseco slug.  I rode and raced CR500 Hondas my whole life, so I am not just whistling Dixie when I say that this feels like it is in that same league.  I can lift the front wheel any time I want, it runs better and stronger everywhere and will go something around 90-100 miles on a tank of pump gas.  Slow, technical trails are easier with the increased torque and the horsepower situations like sand and loam are a riot.  Pulling out of a corner at low RPM does not require a downshift or even clutch work, I just open the throttle and compensate for front end lift which comes on in the mid-range.  FTR I live at 4800 feet, so .035" off the head at sea level might not work, but it sure does work here.  A better reference for milling is what is left over which is .035" piston to head clearance after the gasket swap and the head milling.  If you want an orange rocket, this is the formula. 

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