99 WR400 mods help

I help a friend do his WR400 mods, throttle stop, exhaust cam timing and removed the baffle. The bike has sat for a year or two before the mods. Cleaned out the carburator. We live in the desert at 3000 ft elevation. 1) we have to really bump up the idle stop position to get it to idle (and it "seems" close to idle rpm) and 2) the header pipe will turn red just riding it up and down the block one time. The airbox cover is removed and it has an on-road conversion kit installed. We rechecked the cam positions with TDC and they both looked good, we check the throttle position sensor and it was good. The article for the cam mod said that stock jetting was fine for these mods, but with the header pipe turning red, I'm concerned somethings not right.

my first thought would be that its lean for sure

turn out the fuel screw and i would suggest getting a number 48 pilot

Is it lacking in performance because the CDI went down on mine and gave the same symptoms? Red hot pipe all the way round, popping in the exhaust and hardly any power. Bought a secondhand one and it was fine. Yesterday though, whilst riding, the symptoms came back!!! Don't trust it now! Maybe I need to buy a brand new unit.

my first thought would be that its lean for sure

turn out the fuel screw and i would suggest getting a number 48 pilot

I agree with Brettv, my 99 Wr400 got the header pipe cherry red in just a few of seconds. I put the JD jet kit in it with bigger pilot and main jet with a triple tapper needle (factory needle is a double tapper) it ran better/cooler than new.

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