CRF250 X, JD kit plus DR D exaust system = Lots of power only on top, advice please

[motoadventures_Costa_Rica]

Put a JD kit and DR complete system.

To my disapointment and contrary to what I read in reviews in these forums, It gained lots of power on the top rpms but lost the low end dramatically.

Is ther a way to fix these and not loose my investment?

[c91x]

what's your jetting at ? that would be the first thing i would check because the Dr d pipe gives some good low end power

[motoadventures_Costa_Rica]

main jet is 160, as per instructions with the removed air filter screen

[slodsm]

What about pilot jet and air screw settings? What altitude and temp as well.

[Guest penguin]

pilot jet, fuel screw setting, needle clip position?

[Dark]

Did you open your airbox up, the X has a really restricted airflow compared to the R. If you have already done this, then i would doubble check your jetting. Otherwise, try the airbox, then rejet and see how it runs.

[motoadventures_Costa_Rica]

Pilot jet is stock

Airbox open

Needle position as per instructions in JD kit

Airscrew (no idea)

altitude : From 3,000 ft to sea level

Temp 70's 80's.

The bike has become from the easiest bike to ride to a bike hard to ride, with all the power on top only (lots of power though)

[motoadventures_Costa_Rica]

Just checked airscrew and is 2 1/2 turns out , and needle in the 5th position from top.

[motoadventures_Costa_Rica]

Please anyone have any ideas?

[mtbstuff]

Try a 42 pilot...made a difference on my X.

Also....move the needle up and down and see if it helps in either direction.

Also...if you're in Costa Rica...your bike may have different jetting from the factory...and last time I was there, you had some pretty funky fuel...which is going to add to the mix

[motoadventures_Costa_Rica]

It has a #40 pilot

Will try to find a #42 pilot jet in Costa Rica