hogne

Does anyone have tach. readings for OS 120 III Surpass with pump and 15% nitro fuel. I'm testing with ACP prop.size: 16x6 , 15x8 and 15x6. I have troble getting high rpm's, but I'm not sure what to expect...

Flyer95

My Feedback: (1)

I have this engine and it will turn a APC 16x6 @ 8500rpm, 15x6@9800rpm on 10% nitro and 20% oil castor/syntetic blend.

I liked the 15x6 better than the 16x6 for funfly aerobatics and hovering but a 16x6 can be used on a scale project.

Super08

My Feedback: (2)

Just ran my fisrt tank though and I am showing 8500 on a Zinger 15 x 6-10 with the idle at 1950. I will post more results after I get it broke in. Plan on using Xoar 16 x 6 with it on a GP PT-17.
1,400' alt
70 degrees
Xp Fuel Pro Extreme 15%

Super08

My Feedback: (2)

Update to my above post. Changed to a Xoar PJA 16x6. RPM is hitting 9,000 (peak) but will fly at 8800. Tthe idle is around 1800. I will have to pull the engine though as it has a leak around the pump. I think it is just the fuel line so I will put some keepers on them. Engine has 5 tanks of fuel run through it. The muffler vibrated loose and came off the end of the flex pipe when I was on the third tank. It gained over 200 rpms and wasn't much louder. I put it back on for now, but it got me thinking....

Flyer95

My Feedback: (1)

Mine is inverted in a Diabolic 3D and I had some time flying it today with APC 16x6 and it ran just fine and is very quiet with the 45-degree DuBro exhaust extension on the end of the muffler and it also helps keeping the airplane even cleaner.

foresterxt

My Feedback: (35)

I've finally got my 1.20-E surpass (non-pumped) on the test stand. I purchased used from Motorman57, but I believe it was just broke in. Anyway, I put a MA K series 16x6 and got 9100rpm richened up a click or two for flying. Idled at 1800rpm. My numbers were better than I expected. I was hoping for upper 8000's. It was run with Omega 15% at about 150ft, 63 degrees outside.

Regards,

Dave

hogne

There must be something seriously wrong with my motor. My tachometer-readings shows only 6300 rpm with 15x8, and 6100 rpm with 16x6, using fuel with 15 % nitro and 18 % oil............... I have ordered new ball-bearings, and that will hopefully solve the problem [&o]

Super08

My Feedback: (2)

Yes it should be higher than that. I switched down to 10% and I am still getting about 8600 with an Xoar 16x6. Enige has less than a gallon of fuel through it.....

SuperNash

OS 120 III pumped
std silencer
5% nitro / 15% synth ML70
50' alt
plug - think it is an ASP 4 stroke.


APC 15x7 9100

idle rock solid around 2500, could easily go some slower
throttling superb, no loading up, even after extended idle


old graupner gray 16x8 7200

throttling slower than the APC