I sold my 60 sportster kit to my father cheap too. Wish I had kept it. I have just got myself a 65 LA brand new for £49. I could'nt resist. I have 3 bush bearing 60 class engines now and I'm gonna test them all. O.S LA 65, O.S FP 60 and a K&B 65 sportster all brand new ready for break in. I have looked at alot of 61 ball bearing engine readouts and was not that impressed with prop rpm's they just have not got alot on the bush bearing engines. And there are a few good 50 size engines that can match them ie weston uk and the webra oh and MVVS. I only have 1 ball bearing 61 but that's a Fitzpatrick. All of my other engines that I use for good power in 60 size planes are 70 class engines they are about the same weight but notibly more power than my bush bearing engines and the ball bearing engines. Irvine .72, Super Tigre G75 , Profi .76. I don't think that the 65 la or the fp are that light around 530 grams without exhaust but should be good to see how they compare against each other. But I will throw this in to get your head around the lightest 60 class engine I have is a russian Zeus .61 at 476 grams it's real light that is with the exhaust on it 416 grams without I had to measure the stroke and bore just to make sure that it was'nt a 40 just amazing oh and it's a ball bearing engine.