2008 Suzuki LT-A400/F, LT-F400/F ATV Service Manual, Page 175Get this manual
Fuel System:
Transient Enrichment System The transient enrichment system is device which keeps fuelair mixture ratio constant in order not to generate unstable combustion when the throttle grip is returned suddenly during high speed drivingFor normal operation, sum of the air (1) and (2) keeps proper fuelair mixture ratio
I827H1170043-01
"B": FuelAir mixture