Frame swap, now no won't idle, running lean

I just performed a frame swap on my 08 wr450. Now that I have it back together, the bike will idle with the choke on (very high idle), but as soon as I turn off the idle if the thottle isn't opened up quite a bit, it just dies. And this bike pops like mad when engine is decelerating. I pulled the pilot jet and it is clear. Are there any vent hoses or electrical connections that will cause this?

Any ideas what to check next?

FYI - this is the most UN-user friendly bike ever to work on.

Edited by 67baja

Not enough info. You don't say what you swapped and what you used from the old bike. Sounds like a fuel issue, like dirt in a used tank got to your carb and blocked up the main jet and accelerator pump. Or you used a different carb that had different settings from the original..... More info needed on what you did.

If all the intake components are the same, my bet is on vacuum leak.

The guy I bought my bike (an '07 wr450) from financed it and never paid it off so I can't get the title for the original frame. A guy in my race club parted out his bike (an '08 wr450) so I bought his frame (with title). The only thing I changed was the frame. I re-used every hose, wire, nut, bolt, suspension, radiators, seat, tank, sub-frame, air box, plastics, etc from my '07. This is a big job to do with as many freaking hoses and wires this bike has, which leaves lots of places I could have overlooked something.

Vacuum leaks sound likely. I'll check for that next.

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