Yamaha FZR400 1988-1989 Service Manual page 233

CARBURETOR
3. Inspect:
*Float needle valve @
??
O-ring @
a set.
4. Inspect:
*Throttle valve
*Rubber diaphragm
Tears+ Replace.
5. Inspect:
Needle jet @
??
Main jet @
??
Holder @
??
Pilot adjust screw @
??
Bends/Wear/Damage
Contamination + Blow out jets with a
compressed air.
6. Check:
*Free movement
Insert the throttle valve into the carburetor
body, and check for free movement.
Stick- Replace.
as
Replace.