Have a 2005 KX250, have not been able to eliminate the bog from the low end to mid range,and from mid to high, does not come out of turns strong and have to clutch it alot to get it to rev to pick up power. Have tried all the jet and needle settings and changes. I'm about to start changing the KIPs and the power jet solenoid. Am I on the right track?

could be the carbs what year make model ect ?

Hi Ethan,

What you're looking for is called a "crossover". A crossover is an electronic filter for an audio or speaker circuit. In an audio circuit, a crossover is used to prevent or pass certain frequencies or a range of frequencies from passing through it. Since your sub will reproduce the bass or low frequencies, you don't want other speakers to reproduce them. A band pass filter on your door speakers will do this for you. A band pass filter passes only a range or "band" of frequencies and blocks those that are above and below the range or band of frequencies selected. Installing a band pass filter will prevent the very high & very low frequencies from getting to the door /dash speakers. Likewise, you should consider connecting a low pass filter to your subs, too. The low pass filters work a little differently from of the way band pass filters work - they only allow low frequencies to get to the sub - blocking all the other higher frequencies (your other speakers are better suited to reproduce those). Lastly, you would install a high pass filters on tweeters. Tweeters are designed to reproduce only the high frequencies - sending mid and low frequencies to them is wasting power and can cause damage to them.

You purchase the filters for specific crossover points (the block / unblocked point) as determined by the individual speakers. If a sub has a frequency response of 20Hz - 100Hz, a low pass filter of 100Hz would be ideal. Remaining filters would need to begin at 100Hz - assuming the mid-range speakers have a frequency response beginning at 100Hz. A band pass filter of 100Hz - 3KHz would fit the bill nicely if the mid-range speakers go up to 3Khz Match the high end of the band pass to the high end of the frequency response of the mid-range speakers. Next, a high pass filter at 3KHz would allow only the high frequencies to your tweeters. Basically, you want to have the entire audible range 20Hz - 20KHz covered by the speakers and have the crossover points that match the frequency response ranges of the speakers.

I hope this helps & good luck!

yes it is however the hookup for it requires something a bit unorthodox

you have 4 outputs (bridgeable)

channel 1 and 2 must be bridged (to lower the ohms) then connected to the 2 6X9 in Parallel..
this must then be set to the high pass frequency (eliminates bass)
lower all the settings as low as possible then turn them up slightly to increase volume to a level where its the hardest and clean sounding..lower volume after

this eliminates the bass and keeps the 6x9 pushing your mid range and high range frequency

now you have 2 channels remaining,, set 3 and 4 to low pass and connect each 12" to an individual channel. (this keeps the bass and ohms high so you will get a clean bass to match with mids and high's. Dont set or bridge for a low bass as it will jam out the 6x9 and your music will sound terrible.

so there u have a simple hookup that will work and keep you sounding clean. remember not to raise the volume on the 6X9 too much as you will blow them..

There is reputed and there is actual horsepower!
A reputed 52.5 Hp for the 1990 is not right.
A reputed 57.5 Hp for the 2007 maybe right...at the crank.
You lose 8%-10% at the wheel, 5% more with an O-ring chain.
Standard KX250 would be around 42-45 Hp in peak condition. Intake mods, jets, expansion chamber and some porting changes may give you more but it's give and take...you will lose bottom or mid-range and tractibility will go out the window with a very peaky motor. Computer search KX250 forums and canvas the responses and also look for generic KX250 link's.
Cheers.

hi,most two strokes in the mx range run about 40-1,but me being me i always prefer to run my 2 strokes a little bit oily around 33 or 35 -1,2 stroke oil is very cheap compared to scored barrels or seized big ends...cheers

The carburetor jets, there are 3 bands; A low, mid range and high range rpms. 10k would fall in the Mid range power. I would let the bike warm up a little bit and tweak the middle knob on the left side of the bike and keep in mind you need the right mixture so turn it quarter turn one way at a time per testing the mid range rpms while riding, tweaking 1/4 turns in between tests. If it gets worse, turn it the other direction until you find that sweet spot in the mixture of fuel/oxygen. The carburetor jets, there are 3 bands; A low, mid range and high range rpms. 10k would fall in the Mid range power. I would let the bike warm up a little bit and tweak the middle knob on the left side of the bike and keep in mind you need the right mixture so turn it quarter turn one way at a time per testing the mid range rpms while riding, tweaking 1/4 turns in between tests. If it gets worse, turn it the other direction until you find that sweet spot in the mixture of fuel/oxygen. The carburetor jets, there are 3 bands; A low, mid range and high range rpms. 10k would fall in the Mid range power. I would let the bike warm up a little bit and tweak the middle knob on the left side of the bike and keep in mind you need the right mixture so turn it quarter turn one way at a time per testing the mid range rpms while riding, tweaking 1/4 turns in between tests. If it gets worse, turn it the other direction until you find that sweet spot in the mixture of fuel/oxygen.

yes it might work if u flush it, give it a try

either the oil pressure sender is defective or the pressure relief ball valve in the oil pump is sticking, my money would be on the oil pump pressure relief valve ball sticking.

Pull the slide out and then move the clip on the jet needle one notch lower. Also try two notches to see which helps most. This will richen the mix in mid-range.

Pleas rate thia answer. Thanks v222407! :)

Rebuild the top end. Rings are stuck to the pistons. Grind the valve seats in the process. You have now eliminated the smoking and some of the bog.

Now clean the carbs and install kits. Thoroughly servicing the carbs will eliminate the bog.

Clean or replace the air filter, change engine oil > 10w40 motor oil. Lube and adjust the chain and all cables. Install a fresh set of stock NGK spark plugs and check for spark. Balance and sync the carbs. Be certain the battery is good and strong. Lastly, remove the water trap from the bottom of the gas valve,( petcock ). If the bowl has any water and or rust in it, clean it out. Now remove the entire fuel petcock and clean it up so gas can flow freely. Clean up the inside of the tank as best possible. Re-assemble the petcock etc.,

Doing the above will put you back on the road for a very long time.

Please rate this solution as a "FixYa" if able. Thanks!