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Derestrict klx250 2009 EFI for FREE

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Derestrict for free

1. Disconnect ECU from the rubber base (A)

2. Locate the light green wire (:doh:

3. Cut the light green wire close to ECU

4. Add a piece of wire to the light green wire (that you just have cut) to the side that comes out of the ECU (E) long enough to reach (F)

5. Disconnect (F)

6. Connect the wire you added, in parallel to the black/red wire (G)

7. Connect again (F)

8. Isolate the light green wire that was coming to ECU (D)

klx2502009.jpg

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So, what does this do exactly? Given the nature of the KLX, it would seem unlikely that this would "unlock" some kind of high performance ECU programming.

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I'm guessing that would bypass the rev-limiter on some of the Asian-market bikes?

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Yes, it bypasses the rev-limiter on some of the Asian-market and Europian bikes

that come with EFI. You lucky Americans still have carbies so mods are very easy.

Stratos

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Thank you Stratosa, easy to do and added a tucked away a switch to easily go back to previous configuration to compare results.

Very nice to be able to hit 9000 rpm in all gears now; our, made in Thailand, FI engine's are rev-limited in 4,5,6 to only 8000 rpm. My D-Tracker was only able to reach 7400 rpm max in 4,5,6 resulting in a top speed in 5th and 6th of only 112 kph.

Cheers

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Haven't even tested that yet, I normally only cruise 90 or below but the difference of having the RPM's hit 9000 in 3-5 allows the little bike to reach 100 much quicker. I'll post the pictures of my install when I get back home.

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1) Cut the light green wire close to ECU, add a piece of wire to the light green wire (in my case blue wire)

http://i584.photobucket.com/albums/ss281/stratosa/P5221181.jpg

2)Connect the wire you added, in parallel to the black/red wire that goes in this white box. You can see my blue extension going there.

http://i584.photobucket.com/albums/ss281/stratosa/P5221195.jpg

Done 132kph (0$,0 bahts)

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So, what does this do exactly? Given the nature of the KLX, it would seem unlikely that this would "unlock" some kind of high performance ECU programming.

Very Good Question!

I have spent the last few hours trying to figure out how this would work...

The wires of interest -

LIGHT GREEN WIRE

BLACK RED WIRE

BLUE RED WIRE

Standard circuit - LIGHT GREEN WIRE comes from the neutral switch to ECU pin 20 (neutral switch input). This wire is also connected to line side of diode at the interlock diode bank. The triangle side of this diode is connected to BLUE RED WIRE which connects to ECU pin 12 (starter lockout switch).

Modified circuit - LIGHT GREEN WIRE comes from the neutral switch to line side of diode at the interlock diode bank. ECU pin 20 (neutral switch input) is then connected to BLACK RED WIRE which is the triangle side of a different diode which comes from ECU pin 29 (side stand swich)

At this stage i can not see a logical reason why this would effect performance?!

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Speed Sensor is only way ECU can know what gear bike is in...

From service manual:

Speed sensor must send 8 signals (output signal) to the ECU at the one rotation of the transmission gear. The gear position is decided by the signal of the speed sensor.

If the speed sensor system fails (no signal, wiring short or open), the speedometer shows 0, and the ECU sets the low (1) gear position.

So the ECU sets the low (1) gear position, meaning that the (unrestricted) 1st gear map is used for all gears!

So just cut the green and red wire I think, ECU pin 26, or unplug the 3 pin speed sender cable from the front wheel to the clocks to test and use a GPS to see how fast you are going?

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Hi Fishenough,

Can you please tell me if you can now start / crank the bike in gear?

This mod seems to trick the ECU into thinking the bike is in neutral when the side stand is up which would make sense why it revs better in all gears!

Cheers.

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Dear Circuitsight

I think in the way to understand how it works you confuse people.

Why dont you keep your thoughts to yourself until you figure it out?

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These motors are seriously rev limited, having the power just stop at just over 7000 rpm has a great deal of affect on passing power in 4th and 5th. With these simple mods soldered in, taking all of 10 mins, I can hit 110 far quicker as the peak power is around 7000 rpm; pulling quite quickly to 9000 rpm were the power starts to die.

On a slight decline I hit 136 kph today, but didn't need anymore top end for how I drive; but having passing power at highway speeds now is nice. Oh, and I'd pulled the snorkel out to try that also.

Nope - only in neutral.

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Dear Circuitsight

I think in the way to understand how it works you confuse people.

Why dont you keep your thoughts to yourself until you figure it out?

Hi Stratosa,

The sharing and unerstanding of ideas and test results is great way of finding a solution... I sorry if this confuses people but it can be a great time saver especially if means that you don't have to take your bike apart only to road test and find out what ever you have done has had no effect..

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Speed Sensor is only way ECU can know what gear bike is in...

From service manual:

Speed sensor must send 8 signals (output signal) to the ECU at the one rotation of the transmission gear. The gear position is decided by the signal of the speed sensor.

If the speed sensor system fails (no signal, wiring short or open), the speedometer shows 0, and the ECU sets the low (1) gear position.

So the ECU sets the low (1) gear position, meaning that the (unrestricted) 1st gear map is used for all gears!

So just cut the green and red wire I think, ECU pin 26, or unplug the 3 pin speed sender cable from the front wheel to the clocks to test and use a GPS to see how fast you are going?

Very interesting, like a completely different bike, you now need to hold on as accelaration is very much improved.

I am now going to fit a swich and test again. It seems that I may have resolved why the bikes that have been in accident somehow de-restrict themselves. (Running the bike with the speed sender cable (above headlight) dissconnected unlocked the power and it seems to retain power after it is reconnected) Almost like it clears a flag in the ECU code!

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Very interesting, like a completely different bike, you now need to hold on as accelaration is very much improved.

I am now going to fit a swich and test again. It seems that I may have resolved why the bikes that have been in accident somehow de-restrict themselves. (Running the bike with the speed sender cable (above headlight) dissconnected unlocked the power and it seems to retain power after it is reconnected) Almost like it clears a flag in the ECU code!

I am very happy that you derestricted your bike and you feel it completely different, but i am confused again.

Did you follow the procedure i described in the beggining of this topic to derestrict your bike or something else?

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Hi Stratosa,

This is a different method. Your method seems to trick the ECU into thinking it is in neutral gear. My method forces the 1st gear power map to be applied to all gears. (speed sensor fail fall back)

I am still testing this and will report back soon with more detail.

Nick.

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As a fellow rider "Nick" wrote in kawasakiforums http://www.kawasakiforums.com/forum/showthread.php?t=27708&page=4 about my modification:

Hi! It appear that your method tricks the ECU to thinking it is always in Neutral. It basically connects the Neutral Input on the ECU to the side stand sensor. Interestingly, this wire (side stand, the wire you run up to the interlock diodes) comes from the ECU so the modification you found only actually needs a very short piece of cable

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