Back in the early days of Quarter Midget, the engines had throttles. The K&B .15 used a Perry, and I think the Rossi's were also fitted with the same though that was done by the importers or distributers.
I'll add... They had throttles because the rules, in the beginning, required them. If I remember correctly, the rules said the engine had to idle slow enough so the airplane didn't move on its own while idling.
Bill Vail
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