Engine size for Goldberg Eagle

I'm ready to buy my first trainer, and have narrowed choices down to a Goldberg Eagle or Sig Kadet LT-40. During my research, I have noticed
that some recommend outfitting the plane with a midsize engine while others recommend opting for the largest engine available for your particular plane. The Eagle (if I remember correctly) recommends a .29 to .45 2 stroke. I have been considering either a .40 or .46 size. Any pros and cons either way? Is this small difference in displacement going to make much of a difference in the air? I've been looking mainly at OS engines but am open to suggestions. Thanks.
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Provided the engine is a good one, either will be plenty of power for the Eagle or Kadet.
There are pros and cons in getting a less expensive engine, like the OS LA, vs a FX. The LA is plenty of power for a trainer, but you might want more power in a sport plane later. Buying, let's say, an FX will enable you to use it in subsequent planes.
I'd also look at the Thunder Tiger Pro engines. They are good, reliable, powerful, and not too expensive. Dr.1 Driver "There's a Hun in the sun!"
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I suggest a moki 210 that way you can grow into it later.................. just kidding Get the better motor like a 46 ax the new version of the fx in the 46 size A quality motor will keep you in the sky while learning and not repairing damaged planes from DEAD sticks os motor are user friendly an good quality .............. nobody ever complains about quality la is a non ball bearing motor and is very reliable also , but just don't have the peak performance of a ball bearing motor

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On 3 May 2004 13:54:17 -0700, snipped-for-privacy@hotmail.com (Ann) wrote:

Don't forget the K&B .40 - stock number 4011, ringed version.
Runs forever, hauls an Eagle around with all the pizaz . . . . pizzaz . . . . gusto you'll ever need.
Methinks the Eaglet and later Eagle .40 were designed for the K&B.
Price is within a buck of the O.S. engine. Cheers, Fred McClellan The House Of Balsa Dust home.mindspring.com/~the-plumber
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Hi, we went a different way with ours. Our thinking was: If flying from grass, a larger engine will over come the the drag of the grass better and you will get better takeoff speed quicker. Less time on the ground. I would recommend any of the .46 to .51 engins out there. We powered our first with an OS LA 40 and I was able to horse it off the ground but a begginer would have trouble. We then switched to an OS LA .46 and it was much better. My brother had a Supertigre .51 on his and it was better yet. Go to the bigger engines and you can use it on your next plane also. My .02 cents worth, Dan.
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Don't worry about overpowering....remember, you can always throttle back but if you don't have enough power, no amount of throttle will help.

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I recommend larger wheels than the manual specifies if flying off grass. Go with 3". If weight is a problem, use the Dave Brown or GP foam type.
Dr.1 Driver "There's a Hun in the sun!"
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Go
Ditto...
I had a MDS .40 engine on mine and it took darn near the whole runway to get off the ground. It had adequate power when airborne though. Trying to keep a MDS running through a whole flight is another story. Had to put larger wheels on because the prop would hit the grass with regularity.
PCPhill
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I would stick with the upper half of the recommended range simply because these planes are fairly large and always seem to end up heavier than expected. Remember, you don't always have to use full throttle.
-- Paul McIntosh http://www.rc-bearings.com

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