Ah sorry I did not have seen that you had written it already...
I think the engines are turning much more just listen to the sound in this videos:
http://www.youtube.com/watch?v=ZzBMn6Bgw3g
http://www.youtube.com/watch?v=u0MN6NHChZI
In the second video its a 5ccm engine and it turns much more than 40000 I think.
I will tell you more when I try but first I have to finish my jae 21g for my nova and I need size of the sponsons...