RD400 Ignition Timing Setup Process

Here’s how I set the ignition timing on my Yamaha RD400 two stroke Motorcyle.
Before I got started, I read a lot about the appropriate ignition timing settings for RD400’s and I found out that while the factory spec is 2mm (0.080”) Before Top Dead Centre (TDC).
Preface: I only had a standard dial indicator (in inches), so I had to convert the travel dimension to inches.
NOTE: keep in mind if you have any modifications to your engine, carburetors or exhaust, it would be a good idea to set the timing to 1.8mm (0.070”) instead. My bike was bone stock at the time when I filmed this clip.
A couple of steps that I didn’t show in this video are:
1. Setup the dial indicator so it touches the piston. You might need an extension.
2. Turn the motor over counter-clockwise (anti-clockwise) until the dial indicator stops moving. That is TDC
3. You’ll have to turn the motor over numerous times, or at least back-and-forth from TDC, until you are certain that is highest point of the piston travel
4. Be sure to ground your spark plug straps and don’t leave the key on for longer than you need to adjust your timing.
5. Turn on your keyed ignition
6. Turn your motor over until the plug sparks.
The video will give you more indications of what you’re looking for.
NOTE: You’ll need to time each cylinder separately.
* Please like and subscribe to my page to be notified on my new RD400 content *