I am interested in the Excelleron 90. From what I have read it is a great ship.

I own an OS 91 4-stroke engine that I would like to use. I will either fly Sportsman or Intermediate type maneuvers. I understand that many pattern contestants are using YS110/YS120 4 stroke, OS 91 2 stroke with this aircraft. Again I am trying to use an engine that I already have. Do you think it will fly the maneuvers of Sportsman or Intermediate with an OS 91 4 stroke, no pump?

Thanks,

ed

P.S

If the above will not work, give me some choices in ARF's that will work with my engine. I think the Excelleron 50 is to small.

Ed,
The Excelleron 90 is lightweight for its size but it is a large 90 size airplane. It would
fly OK and probably get you by in Sportsman class but be very limited in vertical
performance. I don't think it would be nearly enough power for the Intermediate class.
Remember , even Sportsman has some maneuvers that require some vertical power.
This might be a good way to get started though , you could start with your OS .91 in
the Excelleron 90 in Sportsman and when you get ready for Intermediate you would
already have a good enough airplane , just need to upgrade the engine. The smaller
airplanes are just not as smooth and easy to fly as the larger ones.
Right now the 90 size is priced lower than the 50 size anyway!


tommy s

ED

funny thing is that i went through exactly the same dilemma as yourself!
i bought a os91 FS II because they are on sale here in Aus and i have wanted one for a while... i also bought an excelleron 50 ARF. Some people thought it was way too much motor for the plane, but it is a biggish plane with a fairly thick wing. The instructions on the box state up to a 80 4 stroke; well the 91 is bugger all difference! I considered an OS70 surpass II, but the 91 was only about 2mm wider in the crankcase and 7mm taller...

As it is, the rocker cover only pokes through the cowl by a smidgen...
I cant believe that a 40 2 stroke would have been enough to fly the plane..
As it is, i havent finished construction yet, but i am sure that it will be "agile".

One thing i did, was to add some reinforcement to the engine bearers.. i epoxied in some hard triangle stock where ever i could and also in the tank area... then i glassed inside the tank area to add more strength.

I am hoping the rubber isolation mounts will help take some of the vibration out of it too!

The other members on this site that have the excelleron 90, believe the 91 4stroke, is way too small to power the plane..

let me know what you end up doing....

mike