Original setting parts to bring out the potential of the stock carburetor! KEYSTER fuel adjustment kits for over 500 models!

From mopeds to liter bikes, meticulous settings for discontinued carbs!

A carburetor combines the appropriate amount of gasoline and air to create a mixture according to the negative pressure and flow rate of the air that the engine draws in. Inside it are pilot jets with small holes, main jets, and jet needles with pointed tips to measure the gasoline. When a manufacturer develops a bike, the carburetor specifications (i.e., jet hole diameter and needles) are determined based on the stock condition of the engine, exhaust, and air cleaner box. However, when customizing the intake and exhaust systems, such as changing the exhaust or installing a power filter, the intake's negative pressure and volume will change. And that is when KEYSTER's fuel adjustment kit comes into play.

For stock parts there is usually only one type of jet and needle, but this fuel adjustment kit lets you adjust the mixture ratio of air and gasoline with 3 different sized pilot jets, 6 different sized main jets, and 4 different sized jet needles. The ratio should neither be too concentrated nor too diluted, and the greatest feature of this kit is that it allows for a wider range of settings to bring out the potential of the stock carburetor. In addition to the setting parts, the kit also includes needle valves, float chamber gaskets, and other parts necessary for overhaul and restoration. The fact that the necessary parts for each model are packaged together eliminates the need to worry about stock parts being out of stock or forgetting to order something. From mopeds to large-displacement bikes, this fuel adjustment kit, which is compatible with more than 500 models from the four major Japanese manufacturers, is an essential item for setting up and maintaining the condition of stock carburetors on discontinued bikes.

By replacing the air cleaner box with a power filter and installing an exhaust with better venting, the intake and exhaust balance will change from the stock condition. The basic idea of carburetor setting is to adjust the jets and needles according to these changes in order to get the mixture ratio just right. Whether the mixture ratio is too concentrated or too diluted can be determined from the burnt condition of the spark plugs.

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Provided by KEYSTER PRECISION WORKS LTD.