RE: Welcome to Club SAITO !
Hobbsy you will find that Bolly 13.5 x 6 works a treat. I use one on the duration version of my Lanzo Bomber that is Saito 65 powered. I also use up to 40% nitro at the same time. I had Ed B make me some needle point 13.5 x 6 and x 6.5 "s for the YS 63 and my only problem is I can't get any more though I hear some enterprising people "out there" are actually making clones.