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The Yamaha SR series was produced for an impressive 36 years and 7 months, from June 1978 to January 2017. Over the years, the carburetor system underwent several modifications before the final model transitioned to fuel injection (FI).

As a result, engine starting techniques evolved over time.
For carbureted SR motorcycles, mastering the kickstarting process is essential. Understanding the correct kickstarting technique ensures a smooth and reliable ignition, whether you're riding a classic SR400 or SR500.

This guide provides a step-by-step breakdown of kickstarting methods for different SR carburetor models, helping you avoid common starting issues and get the most out of your vintage Yamaha SR.

Kickstarting a Carbureted Yamaha SR Engine

VM Carburetor (June 1978 – October 1984)

The SR500 (2J2) is equipped with an accelerator pump, while the SR400 (2H6) is not. Despite this difference, the basic kickstarting procedure remains the same:

1. Lightly press down on the kickstarter.

2. Find top dead center (TDC)—this is when the pedal becomes noticeably heavier.

3. Pull the choke lever and decompression lever simultaneously.

4. Do not twist the throttle. Instead, kick down firmly.

For the SR500, which features an accelerator pump, an alternative method can be used:

• Instead of pulling the choke, fully open the throttle 1–2 times, then release it before kickstarting.

• If the engine feels like it’s about to fire, slightly open the throttle at that moment to aid ignition.

When to use each method:

• Cold starts: Use the basic procedure.

• Warm engine (after a short stop): The accelerator pump method is more effective.

Troubleshooting a VM Carburetor SR That Fails to Start:

1. Fully open the throttle.

2. Hold the decompression lever and perform several empty kicks.

3. Release the decompression lever, then kick again while keeping the throttle wide open.

Once the engine starts, adjust the throttle to prevent flooding and stabilize idle speed. This technique is also effective if a kickstart-only restart attempt fails after stalling.

BST34 Carburetor (April 1985 – February 2000)

This carburetor was used in the final SR500 model (1JN) and the SR400 (1JR). While some internal jetting differences exist, the kickstarting procedure and troubleshooting steps remain the same as with the VM carburetor.

If an SR equipped with a BST34 carburetor does not start, follow the same troubleshooting steps used for VM carburetor models to clear excess fuel and restart the engine.

BSR33 Carburetor (March 2001 – July 2008)

The BSR33 carburetor was introduced in the SR400 (RH01J) as an emissions-compliant model. The basic kickstarting method and troubleshooting steps are identical to those for the VM and BST34 carburetors, but BSR33-equipped models tend to be slightly harder to restart after stalling.

To address this issue, a Throttle Position Sensor (TPS) was introduced in 2003, reducing the likelihood of engine stalls. However, if restarting remains difficult, the standard troubleshooting procedure (full throttle + decompression lever + empty kicks) is still effective.

Fuel-Injected SR400 Models (2009 Onward) and Important Tips

The SR400 (RH03J), produced from December 2009 to January 2017, introduced fuel injection (FI) while maintaining its iconic kickstart system. The starting procedure remains almost identical to that of the carbureted models:

1. Lightly press down on the kickstarter.

2. Find top dead center (TDC)—this is when the pedal becomes noticeably heavier.

3. Pull the decompression lever.

4. Do not twist the throttle. Instead, kick down firmly.

The same procedure applies when restarting after a stall. However, if the engine doesn't restart easily, turn the ignition key OFF and then ON to reset the ECU, which can help with ignition.

For riders using aftermarket carburetors such as Keihin CR, FCR, Mikuni TM, or TMR, the kickstarting method is the same as for the VM carburetor with an accelerator pump.

A common mistake many riders make is twisting the throttle while kickstarting. This can flood the engine with excess fuel, making ignition more difficult. To avoid this, always follow the correct kickstart technique and keep the throttle closed.

The SR's kickstart is more than just a starting method—it's a ritual, admired by enthusiasts for its mechanical simplicity and rider engagement. Mastering it takes practice, patience, and repetition. Gain the right knowledge, develop your technique, and fully enjoy the unique character of the SR.

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