Hi Bob,
Wow, thanks for the information. I'm gonna have to try a Jett 1.20 FIRE. I'd still like to put a pump on it (like a Perry/Varsane) so I could mount the tank on the CG. Any problems that you know of with that set-up? Also, who makes the headers - they look very nice. A Jett 1.20 really weighs the same as an OS .91FX ??
As for price - you get what you pay for. Numbers - based on the serial numbers on the Hanno SPecial. I don't think OS made more than 10,000 of them (actually, I think they made about 7,000 of the original version and maybe 2,000 of the MKII). By the time the MKII came out, the YS 1.20 was dominating pattern. The MKII was supposed to be the penultimate .60. Anybody out there ever run one - please comment. Conversely, in 1997 (give or take a year) Great planes sold 40,000 OS .46FX engines in North America - That's ONE year. The OS 1.40RX is still a great pattern engine and I'm sure OS doesn't see a need YET to produce a more powerful, pattern specific engine.
DOes Jett have a web site??
Happy flying!!