High Altitude jetting

[maxfli11]

Hi all. Is there anyone here that has, or does ride in higher elevations?
planning to take my 2005 EC300 to Colorado this July. We'll be riding some pretty thin air. I'd say at least 7-8 thousand feet. Won't take it to the higher passes most likely. Save that for the XR650L, but 13000 ft max if we do decide we can take it. I have no idea what jets are in it at the moment. Only had it a few months. PO raced it. It runs really strong on NE pump gas at 5-6 hundred feet above sea level. I'm told it may not even start where we're going. Any good advice? Emphasis on GOOD.
Thanks

 

[frankinberg]

We ride and live in Colorado you should have a round top air Stryker 1 I would run a168 main jet needle in 2nd from top 42 pilot if you could find a ddk needle would be best

 

[maxfli11]

Thanks Frankenburg! good place to start. It is the round top Air Stryker. Gonna take it apart this week to see whats actually in it. Will update then.

 

[super_rat]

I ride my 2007 EC 300 a lot in Colorado at 9-13k ft elevation.

38 pilot
158 main
stock needle at second position from top, second leanest position

 

[honuki250]

I just bought a 2018 gp300 and going to colordo
Big difference in recommendations
2005 38 pilot 158 main
2007 42 pilot 168 main

What about 2018 gp??

 

[Jacob 'Berg]

I just bought a 2018 gp300 and going to colordo
Big difference in recommendations
2005 38 pilot 158 main
2007 42 pilot 168 main

What about 2018 gp??

It would be better to adjust the jetting based on a baseline setting that you know works for your bike.

What is your current jetting, elevation, and temps?

Typically I have found that a needle adjustment and leaning out the main jet is sufficient.

 

[Zman]

Where are you going in Colorado and what altitudes?

 

[gasser]

I ride out of Salida when I go out to Colorado and a mechanic in the Gunnison area recommended going 1 step richer on the pilot jet and 4-5 steps leaner on the main jet. The 5 steps put me a little too lean on my bike but 3-4 steps leaner should work fine. FYI I ride at 1,000 -2,000 feet in Tennessee and 7,000-13,000 feet in Colorado. Hope this helps.

 

[Zman]

Having your head squish set correctly helps alot when setting Jetting for altitude.