Jetting help please!

07 DR-Z400S

4000 miles

Stock carb with 2" end cap/ no spark arrestor

Stock engine

Stock carb

150 main

25 pilot with stock fuel screw

DJ needle on 4th clip

Fuel screw 2.75 turns out

3x3 mod

No Toil Pre Oiled air filter.

Most riding between 1500 and 4500 ft. elevation Temp(40 - 80)

The problem i am having is low rpm bog once I get to about 2000 ft. elevation.

I live at a thousand and have jetted per recomendations. I feel like it is not getting enough air. It always seems to happen at the time you really need it to blast out of a creek or corner. I am wondering if:

A. The main jet is too high and I should go back to 142.5 stock main

B. The fuel screw needs to be turned in to lean things out.

C. Go to the 142.5 main and set fuel screw to 2.5 turns

These are my uneducated guesses at what I should do. If you could help me that would be awesome. Thanks for the help!:thumbsup:

07 DR-Z400S

4000 miles

Stock carb with 2" end cap/ no spark arrestor

Stock engine

Stock carb

150 main

25 pilot with stock fuel screw

DJ needle on 4th clip

Fuel screw 2.75 turns out

3x3 mod

No Toil Pre Oiled air filter.

Most riding between 1500 and 4500 ft. elevation Temp(40 - 80)

The problem i am having is low rpm bog once I get to about 2000 ft. elevation.

I live at a thousand and have jetted per recomendations. I feel like it is not getting enough air. It always seems to happen at the time you really need it to blast out of a creek or corner. I am wondering if:

A. The main jet is too high and I should go back to 142.5 stock main

B. The fuel screw needs to be turned in to lean things out.

C. Go to the 142.5 main and set fuel screw to 2.5 turns

These are my uneducated guesses at what I should do. If you could help me that would be awesome. Thanks for the help!:thumbsup:

If it runs ok at 1000 feet, but stumbles a bit at 2000 then ..yes it`s getting rich. Could go down one size main.....but most likely not the main...unless you are talking wot bog. Use this to verify the pilot setting ( from frq section).

http://www.thumpertalk.com/forum/showthread.php?t=327405

I think 25 pilot jet is ok.

Erling

clip 3

Thank you Eddie!:thumbsup: I moved the needle to the 3rd clip and went to a test ride up to 2500 ft. with absolutely no hesitation at any rpm. Thanks again for you input.

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