Should I go down a main jet? 2007 DRZ 400S

Hey Guys thanks for reading. Maybe someone can help me out.

Should I drop a main jet size and go dwn a clip or two? Heres my situation:

Did the 3x3 last year with a dynojet kit(25 pilot 140 main at 800ft above sea level, extended fuel screw) Had a bad bog when I cracked the throttle. I went up and down a pilot jet size to try and fix it but no go, so back to a 25 pilot, which is adjusted within the specs posted on this site. So I went to the third clip on on the needle and things straightened up , untill the bike warms up, then bogs again, BAD.:smirk:

I tested today by blocking the air box 3/4 (pronounced stumble, not any better realy) and then took the air box side cover off(much better! no stumble at all, but no power) I figured I was running rich so I went to the 2nd clip tonight. No more stumble or bog, but doesn't seem to pull like it did before,(After the bog would clear when I cracked the throttle)

Should I drop a main jet size and then try going down a clip or two on the needle jet? would this help fuel delivery and give more power?

Any help would be greatly appreciated. Thanks in advance.

I am having the same issue with my 07 drz400s. I used the JD Jetting followed the instructions for at sea level, cut the 3x3 hole in the air box etc etc... When I cracked the throttle it also bogged down bad. I have my fuel/air screw on my carb all the way to the right and it still will not idle unless i am covering half of the 3x3 hole with my hand. any way to fix this???? Change the jets?? change the needle?? Thanks!

Always jet with your bike at operating temps. Use a clean air filter and fresh gas thru a clean carb.

Cracking the throttle on the stand doesn't mean anything for jetting.

The pilot jet is the only circuit that is in use at idle, so if it won't idle, the FUEL screw needs to come out a turn or two. Turn out to richen, in to lean. Read how to tune a pilot jet and fuel screw.

It sounds like you're both rich on the needle. Raising the clip position leans, lowering richens.

Around 25%-75% throttle, the needle is in play, and when you crack it open, the AP with the leak jet is in use, but chances are, you won't touch that.

just turned the fuel screw out a turn or two the bike idles after a really good warm up. I was cracking the throttle while I was riding in 2nd gear around 33mph the bike would bog down bad and 3rd gear around 44mph the same thing. i will try to raise the clip some time this week. thank you for your help i do appreciate it

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