I hadn’t heard of ABC engines so looked them up. Sources say that a company called A.B.C. Motors Ltd, London, were started in 1912 and was known for aircraft engines including vee, vertical and radial types.
This reminded me about Wankel rotary engines used on a few mower brands including Wolf.
Indeed, Drayton engines and also Blackburne to add to the list.
I have seen on adverts (but don’t know the manufacturer):
Acme & Intermotor (Danarm/Bertolini cultivators)
Oleo-Mac (on their chainsaws)
Komatsu Zenoah
