KA100 Ignition timing

YamahaGuy

Member
Has anyone here tinkered with KA100 ignition timing and willing to share their findings?

Legal range is .080 to .106

Understanding the rule set for these things I feel like I have the knowledge and tools to take a stock one and optimize it pretty close to what the rule set dictates but would love if someone would share their experience with the timing as I don't have a dyno and it's extremely difficult to adjust at the track (seat side of the engine) to do apples to apples comparisons.
 

alvin l nunley

Site Supporter
I know the KA100 is different from a K78, but when I ran my K78, in 1977, I had the timing set at .065". For fuel I ran premium 93 octane. 1 quart of Blendsal Castor to 5 gallons. I won the northern California championship that year. I was running direct drive. Similar to running a dry clutch like your KA100. I got the idea from an article by Gordon Jennings about the Morbideli (s) 250 twin. They were known to set their timing very low. It's worth a try.
 
More advance (.106) will give you a little better low end at the risk of detonation if lean. Less advance (.080) will give more top and over rev.
What you could do is premark the stator with the motor off. Then at the track just line up your preset marks for testing. Fuel will make a difference so use the same stuff as much as possible.
 
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