KX 250 2001 Power Jet

[kshackleton]

Hello All;

I have a question regarding the power jet....what is its specific function and at what point does it work?

I have a good handle on the pilot jet, needle, and main jet functions....I am curious as to when [and how] the power jet comes into play on my '01 KX 250.

Is the power jet related to the fuel cutoff solenoid?

Thanks

 

[MX Junkie]

Is the power jet related to the fuel cutoff solenoid?

Thanks

yes

 

[kawamaha]

how it works:
http://www.supercross-online.de/e/KX250e.htm

or better - should work. imho (i made several tests) it's a gimmick...

 

[kshackleton]

yes

Thanks for the insightful and verbose response.

Seriously though....does the fuel cutoff solenoid open the power jet at high rpm/acceleration to admit additional fuel?

If so, then the power jet is not functioning under normal conditions.

 

[MX Junkie]

Thanks for the insightful and verbose response.

Seriously though....does the fuel cutoff solenoid open the power jet at high rpm/acceleration to admit additional fuel?

Yes

 

[kawamaha]

Seriously though....does the fuel cutoff solenoid open the power jet at high rpm/acceleration to admit additional fuel?

no/yes!!
power jet is open at acceleration, closed when reaching high rpm!!

 

[Chokey]

The purpose of the powerjet (in thoery) is to ensure a rich enough mixture under a load when the engine is at it's torque peak to make good power without detonation, while being able to have a lean enough mixture at high rpms to have a decent amount of overrev, hence the reason the powerjet shuts off at around 9000 rpm. In real-world use, I've tried my KX with it both connected and disconnected, and found the difference to be subtle but noticeable. If you disconnect the solenoid, the powerjet doesn't close at high rpms, so you lose a little bit of overrev at the very top. It won't affect the midrange pull or peak hp. If you don't scream your engine, you'll never notice a difference with it disconnected.

 

[kshackleton]

Thanks All...so when the solenoid is energized....the power jet is closed...

 

[KXtrailrider]

Yes when the solenoid is energized the power jet is closed, when not energized or unpluged it is open and flowing gas. As Chokey said it helps lean it out for more overrev.