Kx 250f 2007 More power

What is the best thing to put on a kx 250f 2007 for more power.

It has a FMF power bomb and stock tip

Upgrade to an 09+.

Getting a new one soon just need to get more horsepower for this season, this is first year this bikes been raced

No bolt on mods on are going to give you any significant power gains. Bolt on do dads mainly change power characteristics. If you want more power, you need to get engine work done or get a bigger engine.

Ok thanks Does a CDI box significantly help at all?

"any bolt on mod won't do significant power gains"

derp.....

I'd say just sell it now and buy a bigger bike, like a 4faddy daddy

How about the bolt on Big Bore kits.. The 262 kits seem to have the best reviews, still revs, but improved power.

I don't agree about bolt on not adding power. I can't believe someone would say that. Stock tip? I take it this is the muffler and you only have the FMF header. The muffler is more important since the stock chokes the bike. If it breathes better, you get more power. That's why you see all these rednecks with huge pipes coming out the back of their king cabs. You could probably get a muffler for that year for cheap, if you can find one. If moto tassanari makes an air boot for that year, that will give you 1 hp. You can add 1 hp by removing your backfire screen if you have one. You can get some more usable power by going to a 14 tooth front sprocket. Something about the gearing on the KX250f, when you go to a 14 tooth front sprocket you get into the "wide differential tranny". Gives you more 2nd and 3rd and less engine braking so you can carry more momentum. Usually an aftermarket pipe adds 3 hp.

Gear it down....

Gear it down....

Do you have a KX250f?

Do you have a KX250f?

Nope, but its the cheapest and easiest way to get the bike to feel more powerful as it allows the bike to come into the power sooner....

Nope, but its the cheapest and easiest way to get the bike to feel more powerful as it allows the bike to come into the power sooner....

That doesn't necessarily work with a KX250f.

That doesn't necessarily work with a KX250f.

Bull....it works on any bike!

This is a pretty cool debate. The 2007 KX250F is powerful enough in the right hands to win races this season, and probably many to come. The best advice anyone will give you is to take the time to dial in your suspension. The stock capability to do this is excellent, and most people who don't post here don't use a fraction of what is already there. Of course, depending on your weight, you may need a different spring set up, but even that is easy to fix. Put it this way, suspension puts power to ground, and it keeps you off the ground and faster in every way.

Originalmonk and Bocephus are right about gearing, even if they disagree. Gearing is much more important than any horsepower advantage because gearing determines when and for how long that horsepower is available to you. Your state-of-the-art machine (yes, it is, even without FI, state of the art) is designed to be easily changed on the cheap to dial in to your needs. Prove it to yourself for $20. Buy a front sprocket with one less tooth than the one you have now, and buy another with one more tooth. They are dirt cheep on Rocky Mountain. Spend the 10 minutes to put the smaller one on, adjust the chain slack and ride. Your bike will feel explosive. You'll also need to shift a lot more frequently. Then try the bigger front sprocket. You will have to find lower gears in the corners, but you will have more room between shifts and your top speed (if you ever get there on the tracks you ride) will be a lot faster. The point is that by doing this you will FEEL a dramatic power change in a way that you will never feel a 1-2 HP increase with any mod, even if you get it, which if you don't jet perfectly, you won't.

Decide which of the three front sprockets you now have suits your needs best. Then dial it in one last time with the rear sprocket. If you like the smaller front, but you want the gears to last a little longer, go down two teeth in the rear. If you like the larger front, but need a few more RPM in the corners, go up two teeth in the rear. All of this ensures that the power you do have is there when you need it. For you, that is when your RPM is from about 7,000 up until it's gone. You are lucky to have a bike that holds that power for a long time.

If you decide to "upgrade" to a newer model, understand that if you have taken care of the one you have, know it inside and out, and dialed it in for you, you may not be upgrading at all. The one you have is freaking fast.

Bull....it works on any bike!

So every bike has the same internal gearing. The KX has its power in the top end. If you gear it down, you will not get to the power. You can go up 1 tooth in the back, but 1st and 2nd gears are useless. We all ride outdoors. We want horsepower on tap at high speeds. I was told by someone who has owned kawi his whole life, adding a tooth to the front gets you into the wide differential tranny. Blake Baggett runs a 13/48. Stock is 13/50.

Dragon67 my suspension is set to my weight (135lbs)

I just got new renthal sprockets and a chain went 13/48

I know that stock this bike has a lot of power and will really get up and go just trying to get as much as I can!

So every bike has the same internal gearing. The KX has its power in the top end. If you gear it down, you will not get to the power. You can go up 1 tooth in the back, but 1st and 2nd gears are useless. We all ride outdoors. We want horsepower on tap at high speeds. I was told by someone who has owned kawi his whole life, adding a tooth to the front gets you into the wide differential tranny. Blake Baggett runs a 13/48. Stock is 13/50.

Think really hard about what you said.....got it yet?

And future reference, a clapped out 07 or any KX250F of any year is nothing compared to a PC bike let alone BBs bike.....

Originalmonk- what kind of bike do you have??

So every bike has the same internal gearing. The KX has its power in the top end. If you gear it down, you will not get to the power. You can go up 1 tooth in the back, but 1st and 2nd gears are useless. We all ride outdoors. We want horsepower on tap at high speeds. I was told by someone who has owned kawi his whole life, adding a tooth to the front gets you into the wide differential tranny. Blake Baggett runs a 13/48. Stock is 13/50.

Bocephus, Blake Baggett's Pro Circuit motor has as much in common with yours as a NASCAR Ford's motor has to the lady's next door. The comparison to a stock bike is precisely zero. The internal gear ratio of his bike is secret. The whole transmission assembly is outsourced and the gear ratio is proprietary. Which means the final drive on his bike is not relevant to anyone except Mr. Baggett and the rest of the Pro Circuit team. Internal gear ratios are not standard.

The power on the KX is at higher revs as you say, beginning at 7,000, but you have to understand gearing. If we gear it down, we not only get to the power, we get there faster. We just don't keep it as long, so we shift up. Lower gearing means we are running higher revs in any given gear, which is where the power is. We don't all want horsepower only at high speeds. We want horsepower where we need it, especially launching out of low speed corners where we can up shift quickly and easily in the power band to the next event.

But, this is technical and it doesn't matter without feeling it, so for under $10 per front sprocket I think Kxracer could learn a lot about his bike in his own outdoors before chasing HP if that's what he wants to do. If he chooses to make the final drive of his bike the same as Blake Baggett's to get that wide differential, he will need a lot more than a couple HP. What do you suppose that Pro Circuit motor puts out? How much speed does he carry into corners? I get the wide differential concept, but that works best with much more powerful motors than ours. . . and faster riders :) Even that said, Baggett's bike is designed for long runaway straights, not our tracks. Kxracer spend the $20 and have fun feeling the difference. You should, too. Then, if I am wrong, you can tell me. That's how I learn. :)

Originalmonk- what kind of bike do you have??

Right now, just my 500exc....

But I've had too many bikes to list over my years!

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