ORIGINAL: a65l
Use the spinner as the Jam nut. I've flown a Saito .56 with a CBI associates spinner adapter in place of the lock nut and not had a problem for many flights. Just put a wrench on it periodically and make sure it's still tight, you should be good.
Andy
Same here. All my enegines have the small solid starter cone and thats all i
use to hold the prop on. Do check for tightness quite often. Never had a problem
yet and have been using them evey since they come out.