A friend with a Johnson powered Nobler once did a perfect wingover except for no pull out. The 90 degree, one point landing on concrete of naturally shattered the engine like a tea cup. As a joke my friend sent the pieces of the engine to Johnson with a letter explaining that while he was admiring his new Johnson he accidentaly dropped it on the carpet. A few days later a New Johnson 35 came in the mail with a handwritten note from Hi Johnson congratulating my friend on his creativity!