RE: ys engine surging at full throttle
Thanks for all the help. Because of the time zone difference I made the holes .007", which are smaller than the #60 size. I only had time to make one flight this afternoon as I was trying out two other airframes but the YS seemed to work O.K. at least it did not do anything nasty. I will persevere and report when I have had a few more flights. The one thing to come out of all this is NOT to buy a second hand engine!! King regards Tony