I just ordered a Sig Senior ARF. This is my second one, the other one was lost last year due to dumb thumbs and the sun! I had an OS 65 on it and it flew great, the OS is on another plane right now, but I have a Magnum 91 4 stroke just sitting there collecting dust. There are only a few ounces of weight difference between the 2 engines and it will be a tail dragger so the nose weight will actually help. Any opinions on the Magnum for this plane? I can always throttle down. The Senior just flies so nice that I had to buy another one. Thanks.


Will

I have a KADET SENIOR ARF too. I fly mine with an OS 55.
My opinion is that a 65 2 stroke is just fine.The 4 stroke maybe a bit to much.

At the very most a 70 four stroke, but still might be too much. A buddy of mine had an O.S. 70FS Surpass on his and it flew nicely at 1/4 throttle. Thing is, that plane builds tail heavy so the extra weight will be needed up front. If you're going with a FS I'd recommend a 4 or 6 pitch prop. Very nice flying plane. A real floater on landings.

Good luck.

Thanks for the replies, I know it will be way over powered with a 91 FS. The 65 2 stroke in my last one would almost hover and it flew nicely on 1/2 throttle or less. I just hate buying a new engine and figure I could just putt around on low throttle settings, I'm not looking to do anything wild with it. It is a great flying plane and I really like it as a tail dragger, it makes an average pilot look really good. I don't get to fly as much as I would like to, this is a nice relaxing plane to just cruise around with. Thanks again.

I have an OS 70 FS in mine and it needed the weight to balance but not the power. The 91 will be okay just either watch the power or set the end point on the servo to not allow full throttle. I have seen two Kadet SRs one with a saito 91 and one with a saito 100 and both flew great. The biggest problem will be vibration of the larger engine so just watch your throttle input.
fossil

I just saw a Magnum XL-61RFS on sale here over in the engines for buy/sale section under four strokes for $100. That would work well. Maybe you could talk him down some.

Fossil,

Thanks, that's what I was hoping to hear! I figure with the big 4 stroke just idling around it should sound nice in the air as well. This is one of the best flying planes that I have ever owned and I have really missed having one. I'll be glad to get this new one in the air. Did you mount your 70 FS upright or sideways?

I have one with a older 90Super tigre great plane will go vertical forever and will just cruise at a high idle for over half an hour on a tank of fuel.