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Old 07-14-2006, 09:14 AM
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Maudib
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Default RE: Extreme Flight RC Yak 54 - 74 inch!

Well, I consider myself a gas guy... very much so.

But when it comes to power to weight... everyone values different criteria... for instance I would never consider a Saito 1.80 on the 68" just too heavy for my wingloading tastes... It certainly would be mondi power:weight ratio though... and I really dig that too, but not at the expense of wingloading.

Now since you love the 68 with a 1.80 on it... then you're the type of person that needs to put a DA50 on the 74"... again I would never think of it... but you'd get a similar feeling aircraft... heavy wingloading but stupid power.

If you are looking for similar power:weight as your 68 was with a 1.80... you will not enjoy ANY of the 35cc or less engines on this plane... as NONE of them will spin a prop the same as a Satio 1.80 will... some will run an 18x6-8 at about 6500-7000 rpm... but your Saito 1.80 is putting out more than that. And the 35cc or under will weigh more.

At this point in time there really isn't anything in the 35cc or under class that is good for great 3D/light wingloading and are more suited for scale applications like a CUB, warbird, etc... UNLESS it's specifically designed ultralight and featuring a canister/tuned pipe... Like the 3W ExtraFun with the 3W28 on a can.

In my opinion the 40cc is right at the turning point for power:wieght ratio and wingloading on a plane this size... but still a little heavy...

Exactly why this bird doesn't have a "gas" recommendation for a powerplant.

When you are at this point... price is no longer a determining factor and it's about the same price to go with a sweet 50cc bird with a DA50... than something in this class with a smaller gas engine... Then you have a great gas powered aircraft with excellent power:weight AND wingloading.

With all that said... guys will fly this thing with all kinds of engines... from 3W 28's to DA50's... Saito 1.20's to Moki 2.1's... And almost everyone will say it's awesome. Because they will be grading with different criteria than you... and that's why we have such a disparage of reports on all aircraft.

It's best to look at what you have liked in the past... compare wingloading, engine/prop/rpms... and extrapolate accordingly... in your case if the 1.80 was hppy on the 68... then you'll need more than 35cc gas on the 74"... and a 1.60 offers more power to weight than a 35cc gas... spins similar props, but weighs 1.5-2 lbs less...