1986-1988 Honda TRX 200SX Fourtrax Service Manual, Page 48Get this manual
FUEL SYSTEM Replace the standard main jet with the high altitude type 1#921Assemble and install the carburetor Turn -out the air screw 14 turn Stan the engine and adj ust the idle speed at high al itude to ensure prope hig altitude operation
CAUTION
Llstained operation below 5, 000 feet 0,500 m) with the hi II atitude settillgs may {'au ellgine overheatillg and damage1Hallthe #98 main jel ald 11 Ihe air 5crew 114 tl"" when rldilg 10 IV 5,000 eel (,500 11)11) MAIN JET