Sneakypete,

From what the various reviews I have read on the Ryan (MAN, MA, RCM, et. al.) reported they all used the 91 4-stroke. From those flight reports they all say it flies 'scale like'. So what does that mean? It means it flies nicely but it is not going to burn up the sky. It will fly on the wing though and NOT the prop. And this is the way it should be. However, that being said, most guys are used to overpowering their planes and depend on that extra power to help them out of a bad situation. Putting a 90 4 stroker in the Ryan will require that you actually fly and plan your manuevers rather than just twizzle the sticks around.

Now you might ask; "Jeff, you're an accomplished pilot that can fly most anything why did YOU put an OS 1.20 on yours? " There are several reasons.

1. it is nice to have that EXTRA power just in case. The fact that I have a 1.20 doesn't mean I'll be blasting around at full throttle all the time. Far from it. It's more than enough to fly it at half stick. I do know how to manage the throttle. But knowing I have a reserve there when I need it brings extra peace of mind.

2. Nose weight. I was suspicious the Ryan was going to need some nose weight and after installing the engine last night and cheching the CG I was right. My saying is 'useful weight is better than dead weight'. The useful weight in my case is the extra power of the 1.20 The tail on the Ryan is sturdy which translates to 'heavy'. Even though the servos are mounted forward by the wing there is still a lot of mass back there. I even have a 5 cell 1500mAh sub-C pack up front.

2. Price. I was able to get a pumped OS 1.20 for $320. That's a bargain in my book. It was only $100 more than a non-pumped OS 91 4-stroke. So I figured for an extra $100 why not.

In my opinion if you use a 90 it will fly. But you'll be flying the wing. Which is 'scale-like'. If that way of flying is comfortable with you then I say go for it.

hth

Jeff