Dave My son has a OS40 and it did not have enough power with floats to get off the water when flying at a lake that is at 1500 ft and it was 95 to 100 . My 52 did take off but it was a dog to fly. We flew my son's with a YS 63 this weekend on the same lake and it was over 80 . WOW it really performend great. I could almost sustained a hover. The nice thing about the YS is the close fuel system. No crankcase oil on model. I'm going to order a YS63 for mine. I would make a good deal if some one wants to try the 53. The weight of the floats is the reason for the need for more power. Dan

ASLAN, Could you let me know what motor mount you used for the Saito 40a??

Thanks
paulwr