Hey Johnny. I'm going to do some jetting work on a new 525 today. It belongs to my local KTM dealer and he doesn't have much in the way of service so he asked me to take a look at it. He ran the bike for about 5 minutes and the pipes turned the most beautiful blue I have ever seen - presumably due to the extreme lean condition.

I'm not sure if the DVR will be that much different from the DVT. I'm going to try raising the stock needle a clip or two, put in a 45 pilot, maybe a 180 or 182 main and a KOUBA replacement fuel/air screw so I can fiddle with the adjustment easily. Then I might do the BK mod - depending on how the bike runs...but might wait on that until the motor has been broken in a bit more.

I'm going to take some pics of the pipe - and if I can figure out how to do it...post them somewhere on here. I'll also post my results tonight.

I have the blue pipes also. I'm at 5000-8500', 60F-80F right now.

Pilot: 42 to 45

Needle: ODBVT raised it 2 (now 5/7)

Mixture: out 2

Main: 178 to 172 (done by dealer)

I'll deal with the main when I get the low end fixed. Even at this altitude it's still lean on the bottom.

I've been advised to go to the next richer needle => OBDTN in #2 or #3 position.


Corrales, NM

Johnny - I just got home from spending the morning at my dealer working on his 525 EXC. First, I took a pic of the beautifully blued exhaust pipes - reminds me of a Harley! Then I went about checking the jetting installed in the bike. Sure enough, it was just as the manual says...OBDVT/3, 42 pilot, 178 main, only 1 turn on the fuel/air screw (FAS). I changed the clip setting to 5, changed the pilot to 45, 180 main, FAS 1-1/4 turns out and then started the bike. At a fast idle the motor popped frequently and after a few minutes, the header pipes were glowing a dull red for about 6 inches from the head. I shut down the motor and opened the FAS to about 2-1/2 and the red glow returned as before. Then I installed a OCEMN/3 and restarted the bike. It ran without popping and the red glow disappeared. After is was suitably warmed up, I rode the bike in a field across the street at moderate throttle settings. Great low end response and the mid-range feels good. The motor has almost zero time on it so I was very careful with the throttle. Didn't check the plug color but will after the dealer puts a little time on it. Would like to try the OBDTN when he gets one. I didn't do the BK mod to the accelerator pump - wanting to check the results with the stock squirt time, but I noticed it was really long.

I hope my 450 runs like this!

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