Vehicle Selection

Jet Kit

Dynojet offers a wide range of kits to fit any application. Several types (stages) of kits are available to fit your specific needs. Whether you run a standard motorcycle, or a tuned sport bike, DynojetCarburetor Jet Kits can provide you with a simple and affordable solution to all your carburetion problems. Dynojet Jet Kits increase power and smoothness throughout the entire rev range, while maintaining optimum fuel economy. Each Dynojet Jet Kit includes comprehensive instructions which show step-by-step installation and testing procedures to ensure a perfect setup every time.

The design of the needle is where Dynojet spends most of its R&D time. The needle is designed to give the correct amount of fuel throughout the mid-range and is also designed to allow adjustment from groove 1 to groove 6 with little or no effect below 3000 R.P.M.; then with the correct end dimensions, the needle will have little effect on the main jet regardless of needle position. This isolates all circuits from each other and ensures easy set-up of the midrange and driveability.

Stage 1 Kits

Designed for motorcycles with a stock engine using the stock airbox, air filter, and stock or aftermarket pipe. Stage 1 kits are fully adjustable to allow the use of well- designed aftermarket pipes and K&N stock replacement air filters. Stage 1 kits are designed to improve throttle response and driveability – in most cases; power increases of approximately 5% throughout the entire power range can be achieved.

Stage 2 Kits

Designed for motorcycles with a stock or mildly modified engine using a well- designed stock or aftermarket pipe with a modified airbox and a stock or K&N replacement air filter. Stage 2 kits are designed for applications where individual air filters cannot be installed and for applications where airbox modifications improve overall engine performance. In most cases power increases of approximately 8% can be achieved.

Stage 3 Kits

Designed for motorcycles with stock or mildly modified engines using K&N individual air filters and a stock or aftermarket pipe. In most cases power increases of 10-15% can be achieved. However, driveability may be compromised particularly with short stroke high RPM motors. On some modern engine and airbox designs, individual filters and proper jetting offer no performance improvement, yet compromise driveability. In such cases stage 3 kits are not available.

Stage 7 Kits

Designed for race use only or special applications. With the exception of our Harley-Davidson® stage 7 kits, all stage 7 kits are high RPM, racetrack use only and are not suitable for street use.

Thunderslide Kits

Thunderslide for Harley-Davidson® and Buell, is the benchmark in jet kit design. It incorporates the first custom-made slide by an aftermarket manufacturer, something no other competitor can claim. The unique configuration allows precise control over the slide’s range of movement. The slide creates a stronger signal, which improves fuel atomization. This provides more power, increased throttle response and improved fuel economy.

Main Jet

We develop our main jets to correctly serve two functions: Static load and dynamic load. The static load is the fuel received through the main jet in the upper gears, where the tachometer is moving very slow. The dynamic fuelling portion of the main jet is the amount of fuel received from the jet in the midrange portion of the power. Main jets are available to purchase individually, please see sizes below:

BJ Style Main Jet

BJ150 BJ155 BJ160 BJ165 BJ170 BJ175 BJ180 BJ185 BJ190 BJ195


DJ Style Main Jet

DJ074 DJ076 DJ078 DJ080 DJ082 DJ084 DJ086 DJ088 DJ090 DJ092
DJ094 DJ096 DJ098 DJ100 DJ102 DJ104 DJ106 DJ108 DJ110 DJ112
DJ114 DJ116 DJ118 DJ120 DJ122 DJ124 DJ126 DJ128 DJ130 DJ132
DJ134 DJ136 DJ138 DJ140 DJ142 DJ144 DJ146 DJ148 DJ150 DJ155
DJ160 DJ165 DJ170 DJ175 DJ180 DJ185 DJ190 DJ195 DJ200 DJ210


YJ Style Main Jet

YJ116 YJ118 YJ120 YJ122 YJ124 YJ126 YJ128 YJ130 YJ132 YJ134
YJ136 YJ138 YJ140 YJ142 YJ144 YJ146 YJ148 YJ150 YJ155 YJ160
YJ165 YJ170 YJ175 YJ180            


Main Air Jet

This jet allows air into the emulsion tube to mix with fuel being drawn from the float bowl. It controls the amount of fuel that can be pulled from the float bowl in the venturi. Dynojet alters this only to achieve the flattest possible fuel delivery curve.

Page: Needle Jet Replacement Kits

Modern fuels have less lubricating properties and over time, needle jet wear is quite common on certain motorcycles. Some carburetors have what are termed "non replaceable" needle jets and when worn, the motorcycle will experience poor fuel consumption and driveability problems. Dynojet Needle Jet Replacement Kits contain new needle jets and special tools which allow the needle jets to be replaced. These kits are designed to function with the stock needles or Dynojet Kit Needles.