YZ ignition on an MX100?

[Tahitian_Red]

I would like to update the points ignition on my MX100B to a later model YZ electronic ignition.  has anyone done a conversion like this?

[Nathan S]

Yep. YZ125E onto DT125.

Bolts straight onto the 125. The only possible difference would be the 100 crank might have a smaller taper.

[Tahitian_Red]

Thanks Nathan!

Did you see a performance gain?

[Nathan S]

Duuno, as I never rode it with the points ignition. But it 'has to' be better than points - stronger spark, variable advance curve, and a much lighter flywheel.
It did go a lot better than I expected, if that means anything.
With a YZ ignition, YZ piston, YZ carb, but otherwise 100% standard engine (including pipe) - good enough to put me solidly into the midpack of the pre-78 125 class at club level, and comfortably not last in the pre-75 class at the Nationals.