Author Topic: ST 51 setups (Read 1146 times)

Bob Reeves · « **on:** September 23, 2006, 10:07:21 AM »

Now that I have all but committed to stuffing a ST 51 in my Skylark what setup is working with these engines. How much fuel do they need for the pattern, prop?

I have a bunch of surplus Rev-Up 12-5's, would be a good thing if I could use them. Planning on making a sprinkler venturi scaled from the stock venturi numbers, thinking it should be close to stock performance. Might send the piston and cylinder to Bowman for one of his rings...

Anybody running one of these things... tell me the good.. the bad and the ugly..

Louis Rankin · « **Reply #1 on:** September 23, 2006, 10:28:10 AM »

Bob,

I run a ST51 on my Bear Profile. Wish I had know you were going to this setup, I would have brought it out the field last weekend; however, here is my setup:

-ST 51 Control Line version Box Stock, no mods.

-Fuel: Lou's Brew 10/20 with a one ounce kicker of Aero One. Lube mix is 75% Klotz and 25% castor.

-Plug: Sig R/C Long Idle Bar

-Muffler: Big Art Tonuge

-Prop: Pro Zinger 12X5

-Head Gaskets: One

Launch inbetween 8.3K and 8.5K for a perfect 4-2-4. Will break just at the top where you need and then slow down on the down hill where you need.

It hauls my 56 ounce Bear Profile with no problems at all.

Many run this motor with high lube with low pitch props and at high RPM. I don't like that setup at all. The motor will slow down and run a traditional break as long as you don't over lube it. It has plenty of cooling fin area and the extra lube tends to overcool, hence the need to run at higher RPM to be consisent when you use too much lube.

So, my recommendation is: Low lube (21 -22% max), 5 or 6 pitch, one head gasket, and no mods!!!!!!!!!!!!!! Try it, you will like it!

Bob Reeves · « **Reply #2 on:** September 23, 2006, 11:57:16 AM »

Thanks Louis, sure had fun last weekend, next year I will bring something to fly.

When you say one head shim, are you adding another or leaving it stock. Assuming the ST 51 has a single head shim from the factory.

Your Bear is real close to the weight I expect the Skylark to end up after I stuff the 51 in, do you know off the top of your head what the wing area is?

Louis Rankin · « **Reply #3 on:** September 23, 2006, 01:21:25 PM »

Bob,

Stock with just one total head shim. Square inches on the Bear Profile are about 620 or 630 I think.

Bill Little · « **Reply #4 on:** September 23, 2006, 05:25:58 PM »

Hi Bob,

Louis has a great set up. I used the Rev-Up 12-5 surplus props (still do) on my ST-51. In a 64 oz. SV-11 it had more than enough power. Willis and the guys used to see the SV-11 at Fentriss in the wind and it did just fine.

I used 5 1/2 oz., usually, for the pattern. I have no idea as to the rpm at launch. I just set it in a cackle at launch and it did it's thing. I was using 64 1/2' eye to eye .018s and turning 5.4 laps. One really good stunt engine, especially for the money.

Bill <><

Bob Reeves · « **Reply #5 on:** September 24, 2006, 10:43:37 AM »

Thanks Bill,

Was lucky to have made a 5 1/2 ounce tank when I built the Skylark. The change over may provide an added benefit of not having to measure fuel

Author Topic: ST 51 setups (Read 1146 times)

Bob Reeves

ST 51 setups

Louis Rankin

Re: ST 51 setups

Bob Reeves

Re: ST 51 setups

Louis Rankin

Re: ST 51 setups

Bill Little

Re: ST 51 setups

Bob Reeves

Re: ST 51 setups