I learned a technique from a former user on this forum. He told me to take the propeller and flip it hard against the compression and not through it and the propeller should bounce between the compression strokes fairly easily. I have a BME 102 and it will hit against the compression stroke twice and rest against the third. A friend of mine has a BME 102 and I tried it with his engine and it did it 4 times and reseted mid-way through the travel. His engine is a lot stronger than mine.

Now two points do not make a trend, but I don't have any additional information to go on or engines to test.