2005-2009 Honda TRX400EX/TRX400X Service Manual, Page 104Get this manual
FUEL SYSTEM Screw he pi lot screw he specified number of turn 'from the factory preset positionTOOLSPilot screw wrench (0 type) Pilot screw wrench guide 07KMA-MS60101 and 07PMA-MZ20110 or 07KMAMN9A 100 (U.S.A only)
HIGH ALTrTUDE PILOT SCREW OPENINGtu rn in fro the factory preset position
St art the engine and warm it upAdjust the id le speed at high altitude it the thrott le stop screw to ensure proper hi gh altitude operationIDLE SPEED: 1,400 100 rpm (min" )
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