need help carb/fuel issues

hey guys have a drz400sm, last year the stator went on me at the end of the season. so just pulled the bike out of storage to start working on her.

replaced the stator and got the bike running again, issue i am having now seems to be fuel related.

starts up okay, idels good, however under load dies out, really boggy, burpy. runs like junk, however if you half choke it it runs as it should. good power no bogs.

i know sounds like a pilot jet, but have had the carb apart twice cleaned it. everything is clear and good. im stumped? any help would be great.

mods 3x3 with jet kit fuel screw is 2.5 turns out

fmf slipon

any ideas? thanks guys!

All new gas? Check to see if the fuel filter is clogged with junk? Hows the air filter look?

I would say clean the carb and the jets but you said you did that.

Does running it on prime make a difference?

Do you have good fuel flow from the tank? remove hose connection at carb and check...

Is vacuum line in good shape?, not cracked?

Check the condition of the needle valve seat filter....on top of the needle valve assembly ...item 18 on this diagram...


Mouse in the intake

Plugged filter in tank

gummed up vacuum feed in the petcock

bad gas

Gas is good, intake is clean and filter, ill play with the pet cock see if it make a difference thanks guys

Pilot jet can "look good" but not be completely clear. Use fine soft wire to clean it. Also, if you have the oem vacuum petcock, make sure it has not failed and let fuel leak into the cylinder contaminating your oil. Check oil level and smell it for gas. Also in Craigo's diagram, check the O-ring on the valve body(#18). It can crack an let fuel past the valve which allows fuel in oil from the leaky petcock.

In the future before you store it put a healthy dose of Ethanol specific fuel treatment in the gas and run it through the carb.

For the price of a new pilot jet , just replace it to eliminate that as a possibility ,

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