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More power-less clutch!

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I have a new 2011 stock KX 250f and having trouble on the track getting enough power out of corners to clear jumps without fanning the clutch...also certain sections of the track where there is a jump and nothing to jump too...and so people just roll over it and then immediately there are two doubles and no time for shifting the bike...therefore fanning the clutch to get enough speed or torque...I feel like I'm on a 125 two stroke.

I recently started ridding dirt bikes again after 16 years off...I used to ride 250 two strokes and I could always find the power when I needed it. I'm considering going two teeth bigger on the rear sprocket for starters. And adding some type of "header" pipe...the kind that looks like a snake that swallowed a toy football.

How can I get more low end and SNAP! out of this new KX 4banger without buying a laptop and computer crap...anyone?

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Well if you are used to riding 250 2-strokes maybe you should have gotten a 450 to match that power?

On the other hand, the KXF get´s a lot more traction and should really have no problem clearing any jumps. Gear it down one tooth, work on your corner speed and practice being comfortable jumping with the throttle wide open.

Oh, and keep the revs up!

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I just went from a 08 250sx 2 stroke to my 09 kx250f and I find myself cluthing it out of the corners...and certain jump that come out of the corners..thats when you have to seat bounce...before I could use power to pick up speed now I find that I'm caring speed through the corner! 250f would be closer to a 125 than a 250 2 stroke. Clutching the bike makes it fun to ride! I guess if you want the power you should have gotten a 450.. I had one of those but when you don't have to hardly shift because it has power everywhere I think it takes the fun out of rididng

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dude, how much do you weigh? That kx 250 f should be plenty powerful to bomb any jump. That one guy was right, you gotta keep the revs up. short shift man, them kx250fs don't need you to fan the clutch, unless you weigh like 250lbs. Even then you gotta carry more speed. if you weigh like 180 then just downshift. by the way, the 250f is more related to a 125 than a 250 two smoker. Hold that thing pinned.

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Thanks guys for your impute! I'm 175lbs and 5'10 so I'm in good shape for a old fart of 43 yrs old. It is fun working the bike harder to make it go and this is improving my abilities as well....I'm going to change the gearing just a little...and constantly working on my cornering...because I need the speed for out of corner jumps.

How will a pro circuit pipe or FMF pipe improve the low end? I ran them on my old two strokes and as I recall I got more midrange through the gears....

Next year I may step up to a 450....especially the sand tracks I feel like I'm pulling a trailer!

For now though I am enjoying the KX and experimenting with the forks....the rear shock was easy to dial...the forks are taking me a bit longer. But this discussion board has so many awesome people's impute! Thanks!

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We have a map that would blow your socks off...yeap, blow them off!

The bike is just too rich...and responds really well to ignition changes too..

PM me if you have any more questions, but it's relatively painless...and quick to get done.

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This site often logs me out after I write a response and I have to start over...why I hate computer crap...

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I don't have a laptop and computer mapping device....the dealer told me my KX 250f didn't come with that....only the 450 did...I was set to buy the 2012 KX450f because the mapping could be done manually in a few seconds...I had not done any research on the 250's but knew the KX kicked ass in MX and supercross...I guess the dealer was trying to protect me and steer me into the "right" direction....I really didn't want a bike that resembled the old two stroke CR500's...although I have ridden some...I wanted a bike that was like my two stroke 250's of the 80's and 90's...

That being said...is there anyone in Sandiego county that can help me with my new KX250f and get some better mapping so I don't have to mess with it?

Right now I'm considering changing sprockets maybe n aftermarket pipe to get thing going in the right direction...

I've been away from motocross too long...

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Well going to a 51t will help you I guess. how ever I have my ecu remaped and it kicks the stock map out of the water.. Stay away from dropping a tooth.. 49t sprocket dogs the bike way to much unless you have a super long straights..

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Just read that link you shared....thanks that was helpful insights by MXA...interesting in that they didn't think remapping made any significant changes unless major internal engIne mods were made...I really don't want to spend 600 bucks and countless time and energy going there if it's not effective. Thanks!

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SEAT BOUNCE...never knew what that was till recently...been watching clips of Bubba Stewart and watching his jumping techniques....didn't know there was a name for that...but I have been implementing some "seat bounce" since I got my new KX...tracks now days are completely different and allot of jumps have been added...so I've had to work on that big time...the old MX tracks like Carlsbad only had like one or two jumps and they were not scary at all....

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Humm.. remaping makes a big diff especialy if you have a pipe

it will help even more if you do have porting done..

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I posted it once, but i'll post it again...mapped vs unmapped.

It was so rich stock that under the long loads on the dyno it has misfires...I thought a sensor was wrong...or a oddball bike so I located another to test...and same result.

The first bike I did the owner also has an 09. He felt the 09 romped his 11 stk vs stk, and was ready to sell his 11 and move on to something else.

I mapped it and he reversed his thoughts. He promptly sold the 09 and has not looked back.

On the track it did not misfire stock, but after I settled on the map I felt best, when the rider test road the bike he was blown away...

I've done a few since then for various people - and each one has been blown away. The bike is just too rich in the a/f department stk...

The 12 has gotten rave reviews from mxa thus far. It picked up something like 2 horses on their dyno. While some of this is the dual injector - I'd bet my lunch money its due to proper mapping. Had they ridden a well mapped 11, they would have realized that the 12 has really only gained about half a horse from the 11.

Mapped vs unmapped

stkvshpmap.jpg

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Thanks again for the response...now were getting somewhere:) when you ask questions you often get manny different suggestions...that being said...will use my best judgment in making a informed decision. Sounds like remapping is a good idea...if I can find the right people to do that for me would be stoked! I have a big investment in my new KX...and want to improve it's performance starting with the least expensive and most effective means necessary. My bike is really good...but it needs some of that good ole nasty 250 feeling....especially for quick out of the corner jumps....

I've talked with other 250 riders on the track and watched them struggle in the same areas of the track as me....coming up short and casing it sucks...clutching it with a seatbounce only to barely make it half the time. After discussing taking different lines and techniques with friends and fellow riders...and in my own humble opinion...the bike needs a set of balls...because mine are full functioning...these new computerized contraptions are a "new" generation...and so...hoping some kids (probably wearing skinny jeans but hopefully not)...maybe long socks would be alright...could help a old fart like me get my machine running like a 250 should be....

That being said....(and furthermore ha")....if this remapping works...I love to give CREDIT WHERE CREDIT IS DUE!....I love it when people do what they say they can do!....especially in today's world...that is a extremely rare thing.

Thanks to all for taking time to write down your suggestions and thoughts!

Semper Fi

Daniel

USMC/USA

Disabled/medically retired Veteran

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Let me add to harrp! I was at a private track and let a guy use my ecu to try and he was jumping jumps he had not cleared before he came back and said it felt like it added atleast 4 more hp and a shit tone more snap..

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It's a huge improvement - most people dont realize how much force(work actually) 1hp is....

550 pounds lifted 1 foot vertically in 1 second is 1 hp. So gained 1 or more - is VERY noticable..

Best of all - it gains power early in the curve...which makes clutching less...and easier to get on gas early.

I laughed when I read MXA's opinion...but hey - maybe they got a ringer of test bike from the get go as far as mapping is concerned..(I doubt it). I know way back when in two stroke days the mags all got modified bikes to test hahaaha. They were made to look stock - but they all had goodies.

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All very interesting...I'm ridding tomorrow at Pala...then taking my ECU out and getting it worked on! I'm also looking heavily into aftermarket pipes...Dr D has a complete set up for 619.00 which is 200-300 cheaper than Pro Circuit or FMF...I've not ran any of his stuff before....but I have with pro circuit and FMF....any suggestions on this?

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As far as technology is concerned - the majority of drd pipes I see dont have a heck of a lot...just a plain ole simple pipe.

But often they do run well - have not tested on the kx.

Typically I see the best results from yosh...the 11 kx responds pretty well to a pipe, but an 09 silencer is good too (just loud!).

These days pipes USUALLY dont gain much - but with some "tweaks" that cheat sound they can.

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^ i second yosh. my drd pipe fell apart. the new yosh rs-4 is a great pipe.

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