After getting the OS 120 FS tuned up today -- I had it set way to rich at idle the first day I worked with it -- I can add that the Venus II does indeed have unlimited vertical with this engine. I had thought I would need the 120 FX (2-stroke) for this kind of performance, but the FS will get it done. I tried a few vertical snaps, some inside and some outside, and it just keeps going if you don't overdo it with the elevator and completely kill the momentum.
-- Bob
ORIGINAL: Don M.
I used a Dubro vibration mount on mine ( pictured above ). It is all the mount you need and the only one I use on on my glow engines. The one I used on the Venus II is a #686 which has a bit smaller footprint than the 688. I turned the tank sideways and dremeled a bit of the former out so I could lower it and mount the engine fully inverted - mine is a non - pumped engine. Looks and works great that way. Treat yourself and use an inside header and a flex pipe so the muffler exists under the plane as in the above pic. I get very little residue on my plane that way.
The 120 FS will give you unlimited vertical and only uses 10 - 12 ozs. of fuel per 10 min. flight.