I think that I was as close as I ever will be to putting a drill bit into my forehead tonight trying to balance an aluminum prop spinner! Have an aluminum spinner that I trimmed for a 15x6 prop for a Saito 125.. Anyway, during the first part of the break in process I noticed that after leaning the top end out some, it would hit 10K rpm without much trouble.. So I went today and picked up a 16x6 to slow the motor down a bit. Anyway, now I have to retrim the spinner to get this larger prop in.. Not too much trouble here, but when I put the dang thing back on my top flight magnetic balancer I thought I was going to loose my mind.. I spent almost 2 hours trying to get that thing so that it wouldn't rotate at all.. I was drilling away a few metal filings at a time.. seemed like it would never just right! I did get it pretty close, but I wonder if that balancer is a bit overkill for these engines.. Seems like a piece of dust is almost enough to throw something off balance.. I guess I better steer away from bugs this year..

Anyway, question about spinners, props and washers.. On this 16.6 I put the backplate on first, then the prop, then a set of two washers, then the prop nut/ adapter nut.. It seems like the back of the prop is VERY close to touching the front face of my spinner backplate.. This wasn't such a close fit with the 15.6.. Can I put another washer behind my prop between the prop and the backplate to get a little more space? Not sure if the prop is supposed to be in contact with the backplate or not..

Thanks again!!