YS .63 prop selection and rpm's
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YS .63 prop selection and rpm's
I need some help in selecting the best prop combination for a 3D plane.
Here is the data:
* 4.1 lb Weston UK "Hype 3D" in Florida (sea level & 60-75deg F).
* One gallon PowerMaster YS 20/20 fuel run through engine
* YS Four Stroke plug
* Valves adjusted to 0.1 mm clearance
* needle valve 200 rpm rich of peak (about 1 & 1/4 turns out)
* Will hover at 1/2 to 3/4 throttle but no acceleration out of hover.
Run data is as follows:
* APC 12x7 - 10,700 rpm
* APC 13x6 - 10,900 rpm (current favorite)
* APC 14x4W - 10,100 rpm
* APC 13x4W - 10,300 rpm
Are these numbers about right? It seems like every prop I put on runs about the same rpm. The oddest was the 13x4W which I was told some guys were getting almost 15,000 rpm out of it. Whats happening here?
I would guess it has something to do with propeller mass since all the props weigh about the same. Would wood props be better?
Thanks for the help.
Chris
Here is the data:
* 4.1 lb Weston UK "Hype 3D" in Florida (sea level & 60-75deg F).
* One gallon PowerMaster YS 20/20 fuel run through engine
* YS Four Stroke plug
* Valves adjusted to 0.1 mm clearance
* needle valve 200 rpm rich of peak (about 1 & 1/4 turns out)
* Will hover at 1/2 to 3/4 throttle but no acceleration out of hover.
Run data is as follows:
* APC 12x7 - 10,700 rpm
* APC 13x6 - 10,900 rpm (current favorite)
* APC 14x4W - 10,100 rpm
* APC 13x4W - 10,300 rpm
Are these numbers about right? It seems like every prop I put on runs about the same rpm. The oddest was the 13x4W which I was told some guys were getting almost 15,000 rpm out of it. Whats happening here?
I would guess it has something to do with propeller mass since all the props weigh about the same. Would wood props be better?
Thanks for the help.
Chris
#2
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RE: YS .63 prop selection and rpm's
Try the non-W props of the same size. I like 11000 to 11500. You may have to trim the props to get this. Your rpm numbers are typical. 15000 on a 13x4W? Somebody has a bad tach! Try some CP 30 Heli fuel for a treat.
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RE: YS .63 prop selection and rpm's
We are having the same problems with our Hype. 90% power to hover, doesnt pull out well. Same engine, prop and fuel setup etc... Its hard to back up the good YS name for which I'm crazy about, when it seems that the Weston 50T outflies the plane. How is this possible? [&:]