98 WR400 Carburator problem, help needed

[Apriliacati]

Need some help here guys, I'm trying to help my fiend get his 98 Wr400 running. The bike has been sitting for awhile and wouldn't start. last week I took the carb apart and cleaned the pilot jet, the bike started and ran fine. Yesterday, we went out to ride and the bike wouldn't run, it did start a few times, but wouldn't stay running. It feels like the pilot jet again, checked it, its clean. I tried changing the plug, it started for a few seconds, wouldn't stay running. Is this carb like a 2 stroke,I tried blowing through the gas line into the carb with the float bowl off? I didn't feel any air coming through while lifting or lowering the bowl, is that normal? Is there another jet besides the pilot that would cause this? Any thoughts would be appreciated.

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