Mikuni 38mm Flat Slide Snowmobile Carburetor Carb TM38-102. TM Series Carburetors provide significant performance improvements over older design round slide carburetors. Air flows faster and smoother through the TM Series venturi due to the flat slide configuration and the jet blocks which help create a smoothbore effect. The high velocity of the air flow means a stronger vacuum at the needle jet, providing more precise metering and better throttle response. NOTE: Mikuni snowmobile specific carbs are equipped with a cable activated choke(enrichener).