What prop size are you finding works well on this engine for 3d? Does it have good throttle response with a 13 x 4? Im currently running a 13 x 4 but my engine is not broken in, have 3 flights on it and have it no where near peaked out so the throttle response is not very good. I'm just curious and looking for input.[8D]

Thats the best engine i have bought I put it on my magic an it´s a blast the besT prop i have tried with it is the 12.25 3.75 it has good throttle respone Good luck best for hovering!!!!!

I agree the 12.25 3.75 apc is the best for this engine, i have one in a flip 3D with a hatori 540 pipe. Blistering perfomance with this prop. (13,540 RPM)I have found that my engine has taken a long time to run in properly ( 3 gal) of 5% Synth to get it perfect,

Andy

Thanks for the info , tried a 12 x 4 today throttle response was alot better, still running it rich with about 9 flights on it, but i think its going to be a good engine.

my 50 with 5% and a 12.25x3.75 is doing around 14500 rpm. but it needs a lot more power for hovering with that prop.

Why so stingy on the nitro? Both of my SX 50s are roaring like lions on Wildcat Xtra Premium 15%. I run both the 12.25x3.75 and the 12x4 props. I have one mounted on a Model Tech Magic Xtra 300 and another on a Sig Ultimate Fun Fly -- this engine is super-powers both birds.

The Sig Ultimate below shows an OS FX .46 -- that engine finally went south after 3 years of heavy use; I replaced it with the OS SX .50 (no mods needed for engine mount or even throttle linkage). The change in performance was immediate on the 1st flight this past weekend.

I have a 50 in a Somethin Extra with 13x3.75W prop. Hovers at half- 3/4 throttle. Plane is 6 pounds. The engine was the worst pain in the neck to break in I have ever seen. I thought I had it dialed in good, but everytime I go to fly it it either deadsticks or leans or richens out in the air.[] The servos have problems too. A huge amount of differential on the elevator halves and the right aileron servo is wigging out. Power is enough, but not ballistic. Fun airplane, just got to get the bugs worked out!

PS: Funny thing is, I have like twenty airplanes and a heli, and NOT ONE of them works good enough to fly!


3D-kid330


[8D]JR radios are the ONLY way to fly!

Oh, in additon to my previous post, the throttle response is real good, but the servo is sooooo fast (hs-81 on 6.0 volts) that if you jam on the throttle, it kills the engine.[X(]


3D-kid330



[8D]JR radios are the ONLY way to fly!

How does this engine run inverted - will it idle long enough? and how should the fuel tank be placed for inverted setup?

Vikas

I now have about 15 flights on mine. It seems to be running well. Have been using a 12x4 prop tried a 13x4 prop again today, it seems to have more thrust but the throttle response isnt as good. Going to try a 12.25x3.75 as soon as i can get one.

I have my tank inline with the carb in the wing on a profile fuel lines are a bit longer than i like , but doesnt seem to be causing any trouble.

I've been running these engines hard several years, mostly in the vertical position (ie hover) I found the 13x4 wood and 12.25x3.75 APC to produce the most pull by a good margine, but if the plane is under, say, 4#10oz or so, the 12x4 is much better. It will spoolup and chage speeds RIGHT NOW and seems to be the perfect "granny low", very linear and clean. But for a 5 pounder you really will want one of the others.

also, the 12x4 is REAL weak. The tips break so easy, so I quit useing them until I quit hittin the prop all the time.