I have this engine in my Sig Rascal and it provides plenty of power. The only problem I'm experiencing is with the low speed needle valve. It keeps coming loose and if I don't reset it after every flight it will actually come out. Fortunately the Rascal encloses the engine so tightly the the needle valve cannot come out completely. (Posted on 9/16/10)

I own an os .91 fs and a saito .91 neither run as good as my Magnum .52rfs.Easy to start,perfect idle,smooth transition. Can´t say enough good things about this engine.I just ordered a Magnum .91rfs. hope it runs as good as my .52
Break it in with Castor oil and you will have a GREAT ENGINE. (Posted on 8/31/10)

I currently have two of these that I have been using for more than a year now. They are without a doubt the easiest starting and most consistent running engines I have ever had. Great performance and a super value. Thanks Magnum for such a fine product. (Posted on 8/31/10)

his engine is awesome set it and forget it great for low wing forty size aerobatic planes with a 12/6 prop unbelievable excellent value to fun price (Posted on 8/31/10)

THIS ENGINE IS FITTED TO MY SIG FOUR STAR 40 AND PERFORMS WELL. THE ONLY NEGATIVE IS THE CARB LOCATION WHICH MAKES THE THROTTLE LINK HARD TO ADAPT AND THE AFTER RUN OIL HARD TO APPLY. THEY NEED TO REVERSE THE CARB SO THE INTAKE IS ON TOP. OTHER THAN THAT THIS ENGINE HAS ALOT OF BALLS. (Posted on 8/30/10)

I originally purchased this engine over eight years ago for a Kyosho PT-19. I had barely broken it in when I put the airplane with engine in a storage closet when my job demands kept me from flying. This past year I took it out of storage and began flying it regulariy with much satisfaction. It is one of the easiest, smoothest running 4 strokes I have ever owned. It always starts right up, idles great and hauls the PT-19 around with ease. I sold the PT-19 the other day but have already purchased another XL52 RFS for some future project. After the initial static break in it took about a dozen flights before it became the silky smooth engine it is now. Treat it right and enjoy for a long, long time. (Posted on 8/30/10)

Yep, 4 !! I love these engines. Perfect for the 40 size planes. Very easy to start and tune. They run like "a Singer Sewing Machine", just purr along. Relatively quiet and realistic sound. The only drawback I can find is the throttle lever is located in the middle of the rear of the engine. Ok if you don´t have GAS TANK behind the fire wall! It takes some creative linkage. Why not sell an after market carb manifold to move the carb over to one side???? Then you could have your engine and your gas too! (Posted on 8/30/10)

I have this engine in a 1/6 scale Clipped Wing Cub and it is perfect. I bought it early this year and have flown it a lot. It starts very easy and runs like a top. I have not had to re-tune it at all sence the first flight. I liked it so much that i bought another one and i will be buying more in the future. Give it a try, you will be very pleased with it. From Alpena Arkansas (Posted on 8/24/10)

been flying 52 since january. flies as good as my os at 1/2 the price. i am going to get a 91 to put into my ryan. great engine. (Posted on 8/24/10)

This is an awesome engine which produces great power. I own 3 of these babies. I have 2 of them on my Hanger 9 B-25 "Mitch the Witch" and the perform flawlessly. I also have one hanging from a Great Planes Escapade and it too is a great performer. I own two other Magnums and think they are one of the best performing engines for the value. Hobby People routinely has Magnums Engines on sale, and in these hard times is the only way to go. Several other hobbyist in our flying club are now switching over to Magnums after seeing mine in action.

Keep up the great work Hobby People! (Posted on 8/18/10)