KDX200 snorkel (just not gonna ditch it as we never know what we'll be crossing and that extra inch counts - just ask her! )
No-Toil filter
All the free mods (last baffle drilled out, etc.)
Dynojet 2152 kit

In Dallas at 850 ft above sea level, riding between 0 and 4500 feet (e.g. like for Big Bend Nat'l Park).

Just thought I'd ask for some advice... My initial thought is the 124, groove 3 from the top, 2.5 turns?

 

Sounds good to me, take it for a run and check the plug color.

 

Near sea level! Texas IS flat. #128 for the win.

 

I don't know, Oz...while TX isn't the Colorado rockies, I wouldn't rate it generally flat. It's a big state with a lot of topography change...sea level to almost 9000 feet. I live at about 1500-2000 feet in the west central part of the state. I'm sure Dallas is a bit lower. Where I ride dirt motors and mountainbikes in this pic about 40 miles from my house, there are some decently frequent and tall "hills".

 

Yeah, Dallas ranges between 750 - 1000 feet above sea level (average is 850), depending on where you are... Most of the time, we're riding in that range. But, we're headed to Big Bend here in October and we'll be riding between 1800-4500 feet above sea level. Like I said, I figure 850-4500 will be our range, normally.

We'd change the jets before heading to CO, or the like...

 

Nah #128 main. Tune the needle and fuel screw on the trail. It's a no carb' out job and can be done in 5 to 10 minutes. The bike likes a lot of gas up top (main jet is for 3/4 throttle to WOT.) Don't knee cap your bike, it''l perform better running a bit rich than a lean.

 

I'd agree on overall jetting being set for home in this case. The CV carb has a very good capability of some minor self-adjusting because of the diapham design. It will compensate a bit for higher altitude. My KLR is always set for my 1500 foot altitude optimally, but it performs very well in CO. Imogene Pass at over 13,000 is the only place it chugs a bit as you near the top. Throttle cable pulled slide/needle carb bikes often have a lot more issue at higher altitude. At Big Bend you won't even notice a difference. I can't wait to take my newly acquired '06 KLX250 to Big Bent this year.

 

Sounds like the 128 is the way to go...

TNC - we'll be doing the Burlingua ride in Big Bend, October 24/25. It's part of the AMA/KTM National Dual Sport series. Should be a blast...

 

+1 on the 128

 

Ended up popping for the FMF Q4 slip-on while we were messing about... With the #128, KDX snorkel and No-Toil filter, the bike is transformed!

Thanks to all for the help.