I was wondering the same thing Joe, I searched all over ALIBABA to see if there was a Chinese knock off....but no luck.....I was even wondering how close the Yamaha Banshee Magneto was to the 250R as they're both made by Denso.....Or even if another HONDA model was the same....Do 4 Stroke magnetos share the same magnet configuration as 2 Stroke Magnetos ?
I see DMR - Dave Moore Racing is pushing the ZEELTRONIC as a great replacement Ignition......but it doesn't come with a Magneto and you have to have a good OEM one to make the system work.
Did you reach out to Ricky Stator ? I'd be curious to see if they would be offering the 250R Magnetos again......(personally I think they were an ATC Magneto that was still available so he bought a bunch....a friend bought one and it was a DENSO Magneto
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