Pilot Screw Adjustment

Carburetors control the amount of air and fuel entering the engine to provide the correct mixture for combustion. To do this over a wide operating range, multiple fuel circuits are employed.

Lectron Fuel Systems Now Available from Tucker

Known for making strong, consistent power, Lectron dominates sports like two-stroke motocross, enduro and drag racing.

Grim Parts Co. Fuel Filter for S&S Super E & G Carburetor

The seamless design allows users to run a fuel filter with an S&S Type E and G carburetor on a Harley-Davidson motorcycle, eliminating the need to find a place to install an in-line fuel filter.

Walbro Expands Die Casting Operation in Mexico

Walbro LLC has announced a major expansion of their North American manufacturing operations with the opening of a new Aluminum Die Casting Facility in Los Mochis, Sinaloa, Mexico.

Vintage Machines

What is the goal with the bike – a beater to ride or show queen?

Mikuni Genuine Rebuild Kits for Carburetors and Fuel Pumps

Each Kit contains all the necessary gaskets, seals, and O-rings, as well as any specialty parts that may wear out over time like pop-off springs, diaphragms, needle valves with seats, and float pivots.

Mikuni HSR 42, 45 and 48mm Performance Carburetors

Mikuni American offers a HSR Performance Carburetor Kit for any Harley-Davidson, American Big Twin and other custom applications. The Mikuni HSR42 Carb Kit offers a 25 percent increase in power and torque for Sportsters, Buells and stock Big Twins when used with an aftermarket exhaust system.

CV Performance Premium Accelerator Pump Diaphragm

As a direct replacement for the stock OEM diaphragm, the exclusive CV Performance Diaphragm replaces worn or cracked diaphragms on Harley CV and Harley Keihin “butterfly” carburetors, as well as S&S Super E/G Carbs.

CV Performance Harley CV Carb Vacuum Slide

CV Performance, specializing in tuning and improving Harley-Davidson CV carburetion for over 25 years, is now offering the new CV Performance Vacuum Slide for Harley CV carburetors as a direct replacement for the stock OEM slide. The vacuum slide in a CV Carb controls or influences the majority of the carb functions.

Mikuni BSR33/42 Carburetor Air Cutoff Valve Rebuild Kit MK-405

Mikuni American is now making available Genuine Mikuni Carburetor and Fuel Pump Rebuild Kits for many popular OEM Motorcycles and ATVs where such rebuild kits and replacement parts may not be available from the original vehicle manufacturer.

Mechanisms of Fuel Delivery: The Float Valve

In a previous issue we went over mechanical fuel delivery system problems associated with carburetor equipped engines. The final mechanism of fuel delivery to the carburetor is the float valve. The float valve is a fantastically simple mechanism to regulate fuel needs for the carburetor. Unfortunately, it is often problematic when fuel is left in