Information for Two Cycle Engines used in pattern.

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OS-140 RX

ST 2300 (1.4cu)

Webra 145

OS-160

Mintor 3M 170

3M 140

MVVS 160 Benz

1

OS-140 RX #1

Ron Lockhart

Galloway New Jersey
Tank Size Specify Oz or CC    16oz Type Plug   OS-F  Elevation of test 20 feet
Header OS Pipe Old Hatori .60 size "bent" pipe Temp of Exhaust  
Tunnel Length   38" Temperature Day of Test 
70 to 90 F		 Fuel 1 15%, S&W
Prop Size #1 17x10N  APC RPM for #1 RPM 8000  
Prop Size #2  RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) N/A OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
26 in along header path
Number of Flights Before Bearing Change If Known  N/A Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  1.3 min/oz in sequence
Comments:
OS-F plug.  Idle set very lean.  Never touched pump adjustment.  Had poor longevity with ceramic bearings. I use Mobile One full synthetic auto oil as after run.

 

 

OS-140 RX #2

Ed Hartley

Knoxville Tennessee
Tank Size Specify Oz or CC    16oz Type Plug   OS-F  Elevation of test  1024 ASL
Header MACS 1-1/4" Rise Pipe O.S. T-6010 Temp of Exhaust   130C - 266F
Tunnel Length   38" Temperature Day of Test  95F Fuel 1 Mach 7 - 25%
Prop Size #1 16x14 APC RPM for #1 RPM 7900  
Prop Size #2 15-1/2 12 APC Four Blade RPM for #2 7780
(Idles at 1280 all day long)		 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) 229mm OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
From the center of the plug to first baffle is 19-5/8"
Number of Flights Before Bearing Change If Known  None Yet Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  Approximately 9 0z for Masters Pattern
Sound measurements as measured by distance and Db 89Db at twenty-five feet
Comments:
I started out using a sixty size pipe and the mid range was terrible as the OS Site stated it would be. See http://www.osengines.com/faq/product-faq.html#q266  I purchased the O.S. T-6010 Tuned Silencer and this fixed the problem. The throttle curve is very smooth. The engine is used in a Zimpro Viper shown on the opening page of this web site.

I set the idle to 1750 rpm and it runs just great!
On the four blade prop I set the idle at 1380.

I used the OS-5 plug that came with the engine and later found the OS-F8 plug last much longer and works just as well.

I started with a 16x12 and that just wasn't enough prop. I then changed to the 16x14 APC and this works well.
Sid Austin of Pyramid Hobbies put me on to this setup. Using a four blade APC 15-1/2x12 prop, I find much the same results as Steve Maxwell talks about in his OS-140 RX #7 on this page. I am absolutely amazed at hot slow it comes down hill with this prop. Likewise the vertical is slower but unlimited. You can take off and accelerate in the verticle!

It is interesting to note you must apply some power to get your normal glide ratio on landing. It has a tremendous breaking action and when you touch down it stops very quickly. Throttle management is a must, particularly in level flight.

The 16oz fuel tank is located on the center of gravity.

When I am through for the day, I disconnect the fuel line and run the engine at a fast idle until it quits. No after run oil.

I can't tell you how long the bearings will last. As soon as it eats the original ones, I will post it here.
(218 Flights on the original bearings, ring etc. and still going strong!)

This engine makes unbelievable power.

 

 

OS-140 RX #3

Brian Hebert

Denham Springs Louisiana
Tank Size Specify Oz or CC   450 cc Type Plug   OS-F  Elevation of test  100 ASL
Header Hatori standard with O-ring header flange Pipe
large volume carbon ES pipe		 Temp of Exhaust   120C
Tunnel Length   35" Temperature Day of Test  90F Fuel 1 20% pattern blend Cool power
Prop Size #1 modified 17-3/4n APC RPM for #1 RPM 8000  
Prop Size #2   modified 17-5/8n APC RPM for #2 8200 Fuel if not Fuel 1
Prop Size #3 modified APC 17.5-12n RPM for #3 8300 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) N/A OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 24.5 inches
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  12-13 min or 8 flights a gallon
Comments:
I have run the set up at 23.5 to the first baffle when using the 17.12n standard APC props running the EFI version of the O.S.1.4 running the Syn fuel verses pure caster made no difference on bearing life or temp just clean up. although the injector would get stuck with the caster fuel from time to time  I never after run the motor and always store it nose High

 

 

OS-140 RX #4

Mike Hester

Woodstock Georgia
Tank Size Specify Oz or CC  580cc Type Plug   OS F  Elevation of test  500 ft or so
Header OS Stock Pipe ES 2C140M80 Carbon Temp of Exhaust  
Tunnel Length   38 Temperature Day of Test  93 Fuel 1 10% Omega
Prop Size #1 APC 16x13 RPM for #1 8000  
Prop Size #2     Bolly 16x13W RPM for #2 8100 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) 10 inches OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  around 300 consistently, ring a bigger issue Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  15+
Comments:
My favorite engine. When set up properly, it's so bullet proof even I can't mess it up.

It seems a bigger issue than fuel pertaining to bearing life is cooling air to the crank case. That being said, I have only run a castor/synthetic blend and have so far not had a bearing failure.

Full break in takes a few gallons, mostly in the air and on the rich side. My experience is that it has been pointless to set the idle apart from factory settings before a few gallons of fuel. Then after break in, set the needles and don't touch until the ring fails, so far that's been about 300 flights on every one.

Usually around 300 flights the engine sags in verticals and the transition becomes rough. So far in 3 engines this has meant a new ring and a bearing change for good measure (although none of the bearings were actually bad). Pretty cheap and easy maintenance for 300 runs in my opinion.

Performs well on a variety of props. After running the 17x12, 17x10, Bolly 17.5x12, 16x14, 16x12, and 16x13, the 16x13W Bolly gives the best performance, but is also the loudest. The 16x13 APC is very quiet and has a very nice speed/power envelope for this particular airframe (Typhoon 2000).

 

 

OS-140 RX #5

Verne Koester

Livonia Michigan
Tank Size Specify Oz or CC  20 oz. Type Plug   OS-F  Elevation of test  580
Header Mac's 4742 Pipe E.S. Composites 2C140L90 Temp of Exhaust   Cool Power 15%
Tunnel Length   Test Stand Temperature Day of Test  85 Fuel 1
Prop Size #1 APC 17 X 12 RPM for #1 8300-8500  
Prop Size #2     RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 22.5
Number of Flights Before Bearing Change If Known  ? Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  
Comments:
My figures are from bench tests. The engine is slated to go into a Smaragd if I ever get it. The rpm's I got were consistent with the numbers Jerry Budd posted on the NSRCA Discussion List awhile back. At this point, it appears to be a very good setup but the final tale can only be told in the air. This setup is quite simple. Buy it and bolt it on without cutting anything. The header and pipe are both full length with about a 3/8" gap between the two inside the silicone coupler.

 

 

OS-140 RX #6

Kurt Bozarth

Aurora Colorado
Tank Size Specify Oz or CC  16 oz. Type Plug   OS-F  Elevation of test  6300' MSL
Header Macs 4742 Pipe Bolly 480R  Muffler Temp of Exhaust  
Tunnel Length  Stock header/muffler uncut Temperature Day of Test  90 Fuel 1 10% nitro /  Cool Power
Prop Size #1 APC 16x14 RPM for #1 7800  
Prop Size #2     RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) N/A OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Original bearings / 75 flights Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  12 minutes
Comments:
Both of my engines were slightly rich on the low side. Low speed needle has been rotated right to approximately the 2 o'clock position.  The Bolly muffler is much smoother sounding than the CD metal muffler originally used. Both of my engines have approx. 75-100 flights with no indication of bearing problems.  Both of my engines are hard-mounted.  I have never adjusted the pump settings.  Both start easily and have never flamed out in the air.  I run them conservatively rich.

 

 

OS-140 RX #7

Steve Maxwell

Greenwood Indiana
Tank Size Specify Oz or CC  500cc Tetra Type Plug   OS F  Elevation of test  500 ft
Header OS bent to fit Focus Pipe Bolly MF590r Temp of Exhaust  
Tunnel Length   Temperature Day of Test 85 Fuel 1 Magnum #1, 2-cycle
Prop Size #1 15.5 X12 APC 4 blade RPM for #1 8150  
Prop Size #2  17 X12 APC   2 blade RPM for #2 7760 Fuel if not Fuel 1
Prop Size #3 17X13 APC 2 blade RPM for #3 7725 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) Full length header and pipe fit up tight to each other OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  15 minutes w/ 1/4 tank left
Comments:
All test was on a Focus at 10lb 10.5 oz, the 4-blade has a very slow presentation which can be a product of Throttle management as you can see from the fuel consumption that I fly a lot at low throttle (probably to slow at times). I'm using an OS 7D needle valve only because I had one and the engine (bought used) only came with the blunt needle and it fit, the 7D is about half as long as the long as the long taper, and works great. The 4-blade has good vertical and is a little more work to fly than the 2 blade because of the thrust, the 2-blade seems to pull better lines in the verticals but fly's much faster all around, besides the up line thrust issue the 2-blade seems to do better on the top of square corners, on the other hand the 4 blade  doing a reverse Cuban you can take a nap though, can make as big as you want and have taken up the whole box to do at 225 meters so the power is there, the big issue is throttle management. I'm getting close to a hundred flights and no sign of bearing ware. I love this setup very simple easy to use and hand starts (use a chicken stick please) Even at that I am going to use the Webra on my next project.

Mount Peidmont Dave Brown soft mount, I don't use after run or even run fuel out, leave carb in the cut off position and flying most every day which would make a difference. One of the really great things about the Peidmont Dave Brown soft mount is easy thrust adjustment just tighten up bolts as needed to change. No sign of wear, I did use Locktite on the bolt to insure that they didn't back out.

Have fun fly safe and practice, practice, practice.

 

 

OS-140 RX #8

Jeff Hughes

Columbus Indiana
Tank Size Specify Oz or CC   Type Plug   OS F  Elevation of test  700 ft
Header Mac Pipe Bollly 590 Temp of Exhaust  
Tunnel Length   Temperature Day of Test 85F Fuel 1 15% Cool Power
Prop Size #1 15.5 x12 4-blade RPM for #1 7850  
Prop Size #2   RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Not Known Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  
Comments:
Like Steve, I've gotten used to the 4blades ability to slow the plane down. Makes for a very pretty presentation. I've also used a 16-13N and 17-10N both louder and less down line braking.

 

 

OS-140 RX #9

Rick Wallace

Toms  River New Jersey
Tank Size Specify Oz or CC  16oz Type Plug   OS F  Elevation of test  35 ft
Header Macs Pipe   Bolly 480 Muffler Temp of Exhaust  
Tunnel Length   Temperature Day of Test 75F Fuel 1 20% S&W
Prop Size #1 17x10N   2 blade APC RPM for #1 8400  
Prop Size #2  15.75x10 3 Blade APC RPM for #2 8000 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Changed in June '02 -- 175+ (so far) on the new set set Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  9 Minutes
Comments:
This engine and exhaust combo is a SWEETHEART. One of the easiest engines I've ever had for ease of set up and operation! Stable 1600-1650 rpm idle w/ either 3 or 4 blade props. VERY quiet in the air with 14.5 - 15.75" 3 or 4 blade props 15.75 x 10 3 blade is awesome - pulls great, constant speed -level or uphill,- and best downhill braking I've seen - better than any 4 blade prop I've tried.

At the end of the day I always run it dry and use Amsoil spray Metal Protectant

Not bad for a used engine bought at the WRAMS show swap shop!!

 

 

OS-140 RX #10

Dave Smith

Halifax, Nova Scotia
Tank Size Specify Oz or CC  16oz Type Plug   OS F  Elevation of test  230 ft
Header OST 6010 Pipe   2C140XL80 Temp of Exhaust  
Tunnel Length  41 Temperature Day of Test 75F Fuel 1 20% Cool Power [15&25 mixed]
Prop Size #1 17x12 APC RPM for #1 7680  
Prop Size #2  16x14 APC RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
28.25"
Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  9 Minutes
Number of Flights Before Bearing Change If Known 
UPDATED - Only 140 flights, the bearing had a lot of crud on the rear of both races, plus the retainer. It mostly scraped off with a thumbnail. It was like a brown jelly. The bearing appeared in pretty good shape. Probably lots of flights left, but experience has taught me to change the rears at least every Spring.
 
FWIW, I have an air outlet, top of fuse just behind crankcase.
 
I have never had an engine, where it was so difficult to remove the wrist pin.

The carb will probably never come out! It appears the locking bar is somehow jammed.  With any luck at all, carb removal will never be necessary.
Comments:
Pipe used is the looooong skinny one from ES. Mr Skorepa advised starting at 725 mm to first baffle, which I did. Have shortened the header so system is now approx 715 mm[28.25"]   Still could shorten more, but don't feel I need to. Engine works flawlessly, and will roll a 10 pound plane vertically oos.  16x14 prop too fast, and braking not nearly as good as 17x12.  Will try some 3 blades and 4 blades in the spring.  I use one extra head shim, and a Tetra Carb filter. The filter may also cut RPM a bit; never think to read RPM  without the filter.

 

 

OS-140 RX #11

Wayne Galligan

Waxahachie Texas
Tank Size Specify Oz or CC  20oz Type Plug   OS F  Elevation of test  750 ft
Header Karl Mueller 2.75' Rise Pipe   Home Made 4 Chamber CF Temp of Exhaust  
Tunnel Length  33 in Temperature Day of Test 65F Fuel 1 15% Cool Power
Prop Size #1 17x10 APC RPM for #1 8900  
Prop Size #2  17x12 APC RPM for #2 8400 Fuel if not Fuel 1 Same
Prop Size #3 Mejlik 17x10W RPM for #3 8900 Fuel if not Fuel 1 Same
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From center of the plug to First Baffle In Pipe (Straight Line)
22-3/4 Inches
Number of Flights Before Bearing Change If Known  about 20 min on 18 oz Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  about 20 min on 18 oz
Sound measurements as measured by distance and Db 92.5Db at fifteen feet grass
Comments:
I made a thrust meter from a fish scale to get a feel for what each prop would do. 
17x10n APC  17.5lbs at 8900 thrust 10lbs at 6100
17x10w Mejlik  17lbs at 8900 thrust 9.5lbs at 6100
17x12n APC 18.5lbs at 8400 thrust  10.5lbs at 6100

The 17x12n was the quietest and had the better overall performance then the 2 17x10's.  The 17x10's put me over the 96db level.  Mostly carb and prop noise however the Mejlik was quiter and had better braking but at $35 ea. a little pricey.  In the air 17x12N APC it was very quite setup.  We are going to try another broken in O.S. 1.4 here shortly to determine if this pipe is the setup or if I just have an exceptional engine.  I have extra air piped to the crankcase also but wont know till later on this summer how much it will effect the bearing life. I'm sure these figures would change as the temp and humidity go up.

 

 

OS-140 RX #12

Charles Bradley

Shreveport LA
Tank Size Specify Oz or CC  20oz Type Plug   OS F  Elevation of test  166 ft
Header Hatori Pipe   Hatori Temp of Exhaust  
Tunnel Length  Pipe flush with header, not cut Temperature Day of Test 55F Fuel 1 20% Cool Power Pro Pattern
Prop Size #1 17x12 APC RPM for #1 8200  
Prop Size #2  RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) pipe flush with header, not cut OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  9
Sound measurements as measured by distance and Db 90Db at ?
Comments:
Bought the Hatori header and pipe, mounted it flush, didnt cut the pipe and got 8200rpm very rich, runs flawless and no midrange problems what so ever, pulls my 9lb 2m ship to the moon!

 

 

OS-140 RX #13

Couto Rosado

Lisboa
Tank Size Specify Oz or CC  450cc Type Plug   OS F8  Elevation of test  30 ft
Header OS (72102100) Pipe   OS T-6010 Temp of Exhaust  
Tunnel Length   Temperature Day of Test  Fuel 1 15% Cool Power
Prop Size #1 16x14 APC RPM for #1 8000  
Prop Size #2  RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust  to Tip 245 mm OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  15'
Sound measurements as measured by distance and Db 98db at 1m
Comments:
For me, this set up is a very good compromise. After about 200 flights the Crankshaft was broken near the rear ball bearing (inside the crankcase). I found that the rear ball bearing was very bad

 

 

OS-140 RX #14

Earl Vincent

Myrtle Beach, SC
Tank Size Specify Oz or CC  16oz Type Plug   OS F  Elevation of test  Sea Level
Header OS high rise, fits Focus Pipe   Greave 140 Temp of Exhaust  
Tunnel Length   Temperature Day of Test 85 Deg Fuel 1 15% Cool Power
Prop Size #1 16x14 APC RPM for #1 7900  
Prop Size #2 17x12APC RPM for #2 7800 Fuel if not Fuel 1
Prop Size #3 17x13APC RPM for #3 7800 Fuel if not Fuel 1
Distance From Exhaust  to Tip OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
27 inch
Number of Flights Before Bearing Change If Known 40 Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  10-12
Sound measurements as measured by distance and Db 93db at ?
Comments:
Ran the Greave pipe all summer, did not seem to care which of the three props I used, the 17x13 seemed to have the most pull in verticles and would keep a more constant speed at mid throttle.

With this set up the engine turns bigger props than I ever thought it would, but the top end and mid range adjustments had to be very lean as to not have it load up in the middle bad. After the Nats I started running Cool power 25 % pro pattern and all the midrange problems went away, however I liked the idea of 10 and 15% fuel so I invested in a OS mixture carb, Set up properly it transitions very much like the FI with a good injector. The top end can be set rich which actually produces more power and dropped the db, I was changing bearings after approx 30-50 flights and used every after run known to man. When I switched to a stainless bearing and stopped using after run just run dry at the end of the day this engine has 200+ flights on it and bearing was still tight and clean as a whistle when recently checked. I use one of Jeff Carishs air filters and the sleeve, piston and ring look like brand new with probably 300 flights on it, I did replace the ring on one engine when it was sagging but the other engine I removed the ring and cleaned carbon from back of the ring and the ring groove in the piston and the power came back. I will probably stick with the OS more for parts availability and that in a 10 lb plane, it is all the power I need for now.

A

 

ST 2300 (1.4cu) #1

Ron Lockhart

Galloway New Jersey
Tank Size Specify Oz or CC   16oz Type Plug   OS-F  Elevation of test 100 ASL
Header  Muller
 		 Pipe Old Hatori .60 size "bent" pipe Temp of Exhaust  
Tunnel Length   31.5 in Temperature Day of Test 
70 to 90 F		 Fuel 1 15 to 30% Nitro, S&W
Prop Size #1   17x10N APC RPM for #1 RPM 8300  
Prop Size #2  
17x10 Standard width APC		 RPM for #2 8000 Fuel if not Fuel 1
Prop Size #3 modified APC 17.5-12n RPM for #3 8300 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) N/A OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 26 inches
Number of Flights Before Bearing Change If Known  100 plus Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  12 in schedule flying
Comments:
OS-F plug.  Tank is behind engine.  Uses Pipe pressure.  Has no pump, header tank, etc.  Idle set very lean.  Has Perry carb, though I'm not sure that was a necessary change.

 

 

ST 2300 #2

Bob Pastorello

El Reno Oklahoma
Tank Size Specify Oz or CC    Type Plug   OS Type F  Elevation of test  1050
Header Mac's Pipe Bolly MF 590 R Temp of Exhaust  
Tunnel Length   N/A Temperature Day of Test  95 Fuel 1
Magnum 1, Mixed 50/50 w/ 10% Heli
Prop Size #1 APC 17 x 10N RPM for #1 8100  
Prop Size #2  APC 16.5 x 13 RPM for #2 7700 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) 12" OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  Land with about 3 oz left
Comments:
These operations again - not a tuned system.  Needed more punch for 11 lb pattern model in heat.

 

 

ST 2300 #3

Edward Miller

Hopewell Jct. New York
Tank Size Specify Oz or CC  20oz Type Plug   OS-F  Elevation of test 200 ASL
Header MAC Pipe Vtech from Dick Hanson Temp of Exhaust  
Tunnel Length   Temperature Day of Test  80 Fuel 1 20/20 S&W
Prop Size #1 APC 17x10N RPM for #1 8500  
Prop Size #2  APC 18x8 RPM for #2 8900 Fuel if not Fuel 1
Prop Size #3 APC 17x12 RPM for #3 7800 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) 10 inches OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  
Sound measurements as measured by distance and Db 94db over grass at Glen NY
 
Comments:
Engine mounted at 7 o'clock, standard Mac header with Vtech/Hansen muffler in Hansen Dalotel. So far 24 flights on this combo, runs great, mid range mixture screw on stock ST carb all the way IN. Hi speed needle about 1 3/4 turns out. 

B

 

Webra 145 #1

Matt Kebabjian

Jacksonville Florida
Tank Size Specify Oz or CC   16oz Type Plug   OS-F  Elevation of test Florida; Sea Level
Header
Macs for the Webra, full length		 Pipe OS/Hatori 20cc, for the 140RX Temp of Exhaust   115
Tunnel Length   Temperature Day of Test 
Hot, Muggy		 Fuel 1
15% Nitro; 19% Oil;  Special Blend
Prop Size #1   16.5x13 APC RPM for #1  
Prop Size #2   16x14 N and Std RPM for #2 Fuel if not Fuel 1
Prop Size #3 15.5x12 4 blade APC RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) N/A OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 23 1/4"
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  
Comments:
General comments on break-in of a Webra 145 AR (Blackhead). (The new AeroX (redhead) requires very slightly different set-up, particularly on main needle settings (fewer clicks open according to a friend who has just started using one). My AeroX engine will not be getting run in until the spring, so I cant help much there yet.)

This is how I ran mine initially and hopefully that will help you. Main needle open 40 clicks (about 1 1/3 turns open). Midrange/idle needle open 1 1/3-1 1/2 turns. 10% CP with a 16.5x13 standard blade APC. I have used the standard Hatori/OS pipe on mine from the start, and set the first baffle at 23 1/4" from the exhaust flange; the Bolly muffler, or any muffler, should need no such care in the placement.

Ran it like that for a couple runs, one on the ground and one in the air. Then started the leaning out process, One Click at a time, and five runs each adjustment roughly, until broken in, after thirty tank fulls (2+ gallons).

The final settings were 33 clicks on the main needle (about one turn open) and slightly less than one turn open on the idle needle. After the first gallon at 10% nitro, I started using the 2 cycle blend I like as follows: 1400 grams 30% CP heli fuel and the balance 5% CP (15% final nitro and 19% oil blend). The heli fuel has a less viscous oil which the engine seems to love. The engine smokes more than others but it stays nice and cool. Engine has 107 full tanks through it as of this writing, and the bearings are still feeling like brand new.

My after run procedure is also fairly simple as follows: I empty the tank and leave the tubing to the carb off. The engine is started and it runs a few seconds at idle, emptying the fuel from the pump. I flip the prop about a dozen times more until it no longer kicks. I take the air filter off and add 15 drops of castor oil in it, and crank another dozen times to distribute. That's it

The first start of the day is usually the toughest since the engine has the castor in it from the previous session, and since I never use a starter. This procedure has worked well for me: 1-Vent must be open, after filling the tank. 2-Throttle open full. 3-Hand crank five or six times until fuel squirts out of the carb to the ground (inverted set-up, plane on the ground). 4-Carb closed to idle. 5-Hand crank about ten times and hear the engine get juicy. 6-Attach the battery to the glow plug. 7-Carry the prop through once by hand, feel the bump. 8-Flip against compression. 9-It usually starts in a flip or three.

Needs to sound juicy to start this way. Has never kicked back, not even once, but can start backwards. If starts backwards, I usually close the throttle some more and usually the engine kicks and runs forward. That's it. A lot to write but really easy to do

 

 

Webra 145 #2

Brian Young

Tulsa Oklahoma
Tank Size Specify Oz or CC   16oz Type Plug   OS-F  Elevation of test 670 ft.
Header Macs Pipe Bolly590R Bolly 565 Temp of Exhaust  
Tunnel Length   Temperature Day of Test 
90-95 F		 Fuel 1 15% Nitro 18%Syth oil, I blend my own fuel. Using Klotz Techniplate for my fuel mix.
Prop Size #1   17x10N APC RPM for #1 8100  
Prop Size #2   15x11 - 4 Blade APC RPM for #2 8000 Fuel if not Fuel 1
Prop Size #3 16.5x12N  APC RPM for #3 7800 Fuel if not Fuel 1
Prop Size #4 17x13N APC RPM for #4 7500 Fuel if not Fuel 1 15% Cool Power
Prop Size #4 17x12N APC RPM for #4 7550 Fuel if not Fuel 1 15% Cool Power
Prop Size #4 17x10std APC RPM for #4 7900 Fuel if not Fuel 1 15% Cool Power
Distance From Exhaust Outlet to Start of Pipe (Straight Line) N/A OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
The pipe length from the center of the plug to the tip is 30.5 (this is to pipe outlet),  or from the center of the plug to the high point on the pipe is 12.5.
Number of Flights Before Bearing Change If Known  Just over 200 Flights Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  
Comments:
Easy setup to run, engine is the blackhead version Just received a 17x10 APC Standard, it runs at 7700rpm. (This is a nice prop, quiet, constant speed.)

Post #2 results in RED -This is my previous blackhead engine rebuilt with the Aero-X sleeve piston etc. Its a much better running engine since the rebuild. All the 17" props I've run have the same feel when flying, a moderate pace with good vertical.

 

 

Webra 145 #3

Lee Davis

Chapel Hill North Carolina
Tank Size Specify Oz or CC  20 oz  Type Plug   OS-F  Elevation of test 500 ft
Header Macs, 2 1/4" rise Pipe Greve 2 stroke tuned pipe Temp of Exhaust  
Tunnel Length   Temperature Day of Test 
 		 Fuel 1 15% Nitro/18% Oil
Prop Size #1 17x12 APC  RPM for #1 7950  
Prop Size #2   RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) N/A OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  
Comments:
These comments are for the Aero X (red head) version of the engine.  My company, Piedmont Models, is the US retailer.

Greve Tuned Pipe Setup - 27.5 inches from glow plug to 1st baffle.  ES-Design Tuned Pipe Setup - 23" from glow plug to 1st baffle.

Fuels - Red Max standard 15%, Cool Power standard 15%, and PowerMaster Mean and Green 15% are all good fuels to use and will yield similar results.  Fuels with very high oil content, often used for high performance 4 strokes, should be avoided.  They provide no additional benefit and will usually adversely affect throttle transition.

High Speed Needle Adjustment - typical for 2 stroke, adjust for maximum RPM then back off a couple of clicks.

Low Speed Needle Adjustment - Set idle speed to 2000 rpm or less.  Idle for 30 seconds then transition to full throttle.  If the engine stumbles with a lot of smoke coming from the exhaust lean the low speed needle.  If the engine hesitates with little smoke richen the low speed needle.  Correct transition occurs quickly with consistent exhaust smoke through transition.

Break In - The engine can be flown with little break in, but will require several gallons flown under load to fully seat the ring with the very hard carbon coating on the sleeve.  The high speed needle will need to be leaned a little through this process. 

Fuel use should not be excessive - For example, on 20 oz the plane will fly through the Masters pattern twice with a safe margin of fuel left in the tank.

Use of after run oil (most any lubricant will do) is important to achieve good rear bearing life.  A number of factors are involved, so results will vary, but running the engine dry and applying after run oil will give very long bearing life.  Failure to do so can ruin the bearing in as little as 10 gallons of fuel.

The engine runs fine on a muffler, the Bolly 590 is a good choice.  RPM will drop 200-300 compared to a tuned pipe

 

 

Webra 145 #4

Jim Woodward

Lancaster California
Tank Size Specify Oz or CC   17.5 Type Plug   OS-F  Elevation of test 2000
Header Macs Pipe ES 2C140S90 Temp of Exhaust  
Tunnel Length  36" Temperature Day of Test  Fuel 1 Cool Power 25% Pro-Pattern
Prop Size #1 17 x 12 (regular blade) RPM for #1 8100  
Prop Size #2   RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  11 minutes (masters pattern)
Comments:
Over 175 flights, no problems what-so-ever.  The only fuel used is Cool Power 25% pro-pattern.  Engine is getting better with time.  Original bearings. NOTE:  This engine will idle super low.  Set the idle at around 2000 rpms, or use an idle-up switch in flight, so that you don't have an inadvertent dead stick at the bottom of the 3 turn-inverted spin.

 

 

Webra 145 #5

Paul Bedford

Maple Ridge ?
Tank Size Specify Oz or CC   16oz Type Plug   OS-F  Elevation of test Sea Level
Header Webra Header Pipe Webra Pipe Temp of Exhaust  
Tunnel Length  36" Temperature Day of Test  65Deg Fuel 1 Cool Power 15%
Prop Size #1 17 x 12 Bolly RPM for #1 8300  
Prop Size #2   16x10 3 Blade Bolly RPM for #2 8300 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  
Comments:
The engine is very easy to start in the up-right position. High speed needle valve opened 1.5 turns and after 14 flights have started to turn in. Now at 1 turn open. Recommended pipe length overall was 780 mm. (30 3/4in)  However I left it long 790mm. (31 1/8) Almost to much power. Fuel consumption much less than a YS. Using a 16oz tank for competition. Changing to 14oz. Lighter than a OS. by 3/4 oz. Very pleased.

C

 

OS-160 #1

Matt Kebabjian

Jacksonville Florida
Tank Size Specify Oz or CC   20 oz Type Plug   OS-F  Elevation of test  Florida; Sea Level
Header   Macs 1090 Pipe Hatori RTC
 		 Temp of Exhaust  
Tunnel Length   38" Temperature Day of Test 
Hot, Muggy		 Fuel 1
15% CP; Special Blend
Prop Size #1   15.5x12 4 blade APC RPM for #1 7700  
Prop Size #2   17x12 Std APC RPM for #2 8250 Fuel if not Fuel 1
Prop Size #3 18x10 APC RPM for #3 7950 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) N/A OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 25"
Number of Flights Before Bearing Change If Known  N/A Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  1 1/3 Masters Pattern
Comments:
Am using the topper tank plumbing arrangement outlined in the Piedmont Web Site and in our District 3 Web Site. Very straight forward set-up with the 4 oz topper tank right behind the firewall and the 16 oz on the CG.

Only have about 50 runs on the rig, prior to getting my Webra going, so it is barely broken in and the bearings are still brand new. But the engine is well behaved although it does tend to get flooded some, in my inverted set-up.

It makes a lot of power, on par with the 140 RX or the Webra, but, drinks a lot of fuel. It is far less expensive than the thoroughbreds, but is a heavier rig. It is not as responsive to a pipe as the other engines are, since it is more mildly timed than the other thoroughbred pattern engines. This simply means that the engine will run as well on a muffler.

Break-in settings are straight forward; the idle needle will require to be turned in at least 1 turn from factory settings, so that the engine will hold a rich run and go through mid range okay without stalling. The main needle was turned in one click at a time and several runs were made per new needle setting, until the engine was broken in.

The first run of the day is a little tricky in the inverted set-up, because it requires choking the non-pumped carb. That's a little cumbersome in my set-up. I detest using starters because they mar the mirror finish on my polished spinners, but on occasion, I had to use the device.  The engine wouldn't start easily by hand cranking, without turning the model on its back.

All are minor concerns for an engine that is reasonably user friendly, and puts out a lot of power, for a minimal lay-out of cash.

 

 

OS-160 #2

Bob Pastorello

El Reno Oklahoma
Tank Size Specify Oz or CC   20 oz Type Plug   OS-F  Elevation of test  1050
Header    KS Custom Pipe KS 76-4 Canister Muffler (not tuned) Temp of Exhaust  
Tunnel Length   N/A Temperature Day of Test  96 Fuel 1 17% Magnum (Magnum 1, mixed 50/50 with Magnum Heli 10%
Prop Size #1  Bolly 16.5 x 12 CF 2 blade RPM for #1 8600  
Prop Size #2   APC 17 x 10N RPM for #2 8500 Fuel if not Fuel 1
Prop Size #3 APC 17X12 std RPM for #3 7350 Fuel if not Fuel 1 15% Magnum
Distance From Exhaust Outlet to Start of Pipe (Straight Line) 10" OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 N/A
Number of Flights Before Bearing Change If Known  N/A Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  8 min flight, land with 1/2 tank
Sound measurements as measured by distance and Db 93db, used AMA standard 3m.
 
Comments:
Also ran 16.5 x 12 3 blade Bolly; did not tach, but power was exceptional for Masters/FAI.
 17 x 10N was 94db
16.5 x 13 was 95db, both per AMA 3m Rule
 
Prop Size #3 Hangar 9 digital tach.  Two separate runs.  Motor has about 4 hours on it.  Compression 112 cold with Hobbico compression gauge, avg. of three tests. In the hot wind, this combo didn't pull real well, but it was sure QUIET.

 

 

OS-160 #3

Matt Taylor

Palmsdale California
Tank Size Specify Oz or CC   16oz Type Plug   OS-F  Elevation of test 
Header  Pastorello #2 Pipe KS Can Temp of Exhaust  
Tunnel Length   Temperature Day of Test  90 Fuel 1 Magnum 1 two stroke
Prop Size #1  APC 17x10N RPM for #1 8700  
Prop Size #2   RPM for #2 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 N/A
Number of Flights Before Bearing Change If Known  Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  8 to 10 minutes
Sound measurements as measured by distance and Db
 
Comments:
Easy, reliable setup with the tank at the firewall. Relatively inexpensive, INCREDIBLE POWER! More than unlimited vertical on a typical 2m pattern airplane.

 

 

OS-160 #4

Ben Oliver

Knoxville Tennessee
Tank Size Specify Oz or CC   16oz + 4oz header Type Plug   OS Number 8  Elevation of test  1024 ASL
Header  Karl Mueller Wrap Around Header Pipe Max 1060 Temp of Exhaust  131C
Tunnel Length   31 inches Temperature Day of Test  90 Fuel 1 15%, Mach VII did not run good on 25%
Prop Size #1  APC 17x13 RPM for #1 7930  
Prop Size #2   16x13 APC RPM for #2 8930 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 18 inches from glow plug to first baffle in the pipe.
Number of Flights Before Bearing Change If Known  N/A Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  15 minutes or more
Sound measurements as measured by distance and Db
92Db  at 25 ft on pavement
Comments:
Engine on maple beams, solid mount. Great power. Pipe is on two flexible mounts. Pressure off pipe used. Initially I tried to use a Perry back plate mounted pump. No go. My son Warren Oliver uses the same pump and its great. Don't ask me why. Also one header broke at the engine and the second one is on. Faulty header. Only seven flights on the engine at this time.

 

 

OS-160 #5

Gene Maurice

Plano Texas
Tank Size Specify Oz or CC   20oz DuBro Type Plug   OS-F  Elevation of test  560 ASL
Header  Karl Mueller  Header Pipe Max 1090 Temp of Exhaust  
Tunnel Length   32 inches Temperature Day of Test  70 Fuel Magnum 15% 2 cycle Syn/Cast
Prop Size #1  APC 16x12 RPM for #1 8800  
Prop Size #2   17x12 APC RPM for #2 8300 Fuel if not Fuel 1
Prop Size #3 RPM for #3 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 18.5 inches
Number of Flights Before Bearing Change If Known  N/A Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  12 to 15 minutes
Sound measurements as measured by distance and Db
??? Quieter than my YS 140 in the air
Comments:
The tank mounted on the CG coupled to a Perry Regulator pump mounted near the needle valve. This set-up likes to be lean, no RPM incr. when pinching the fuel line. At that setting acceleration is near instantaneous and the idle is a steady 1700-1800 RPM. So far it has been very reliable, one flame out in 20 flights. This happened while still trying to find the right needle setting.

This thing produces GREAT power and performance for a relatively cheap set-up (all components total < $400). I’ve been using YS’s for almost 10 years and finally got tired of buying $150+ in parts every year and laying out $500-$700 for an engine. The low cost of ownership and simplicity appeal to me. Now lets see if it holds up!!

 

 

OS-160 #6 w/IronBay Regulator

Bob Pastorello

El Reno Oklahoma
Tank Size Specify Oz or CC  18oz Type Plug   OS-8  Elevation of test  1017 ASL
Header  Karl Mueller Custom W/A Pipe Krumscheid (KS) 76-4 MUFFLER Temp of Exhaust  
Tunnel Length   NA- Untuned System Temperature Day of Test  85 Fuel Magnum 14% 18% Oil
Prop Size #1  APC 15.5 x 12 Four Blade RPM for #1 7220  
Prop Size #2   17x12N APC RPM for #2 7350 Fuel if not Fuel 1
Prop Size #3 APC 16.5 x 13N RPM for #3 7410 Fuel if not Fuel 1
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 18.5 inches
Number of Flights Before Bearing Change If Known  Still going 55+ flights, SS bearing
 		 Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern  12 to 15 minutes
Sound measurements as measured by distance and Db
 
Comments:
Ran this setup to try recommendation of Ed.  Four blader at this rpm won't work, but if the system was tuned, and I had 20%, I am positive it would be a "keeper".  16.5 x 13 NOISY setup.. didn't pull all that well, either.  17 x 12N is the best of all with this fuel, this muffler system.

E

 

Mintor Motor 170 (3m) from Italy #1

Jason Shulman

Tuson Arizona
Tank Size Specify Oz or CC   Du-Bro 16oz Type Plug   2 ea OS Number 8  Elevation of test  2700' ASL
Header  3M60mm rise header and carbon pipe (don't know baffle info, header is same as 0S-140) Temp of Exhaust  
Tunnel Length   Temperature Day of Test  60 Degrees Fuel 1 PowerMaster 15%Nitro with 19% oil
Prop Size #1 APC 17x12 RPM for #1 8100 (fast flying speed)
Prop Size #2 16x16 APC RPM for #2 7150 (medium flying speed)
Prop Size #3 15.25x12 APC 4 Blade RPM for #3 7700 (medium flying speed)
Prop Size #4 15.75 APC 3 Blade RPM for #4 7100 (quietest and slowest flying)
Distance From Exhaust Outlet to Start of Pipe (Straight Line) OR Distance From Exhaust  Outlet to First Baffle In Pipe (Straight Line)
 
Number of Flights Before Bearing Change If Known  N/A Typical Run Time in Minutes Per Tank of fuel. Fuel used means consumption As typically used flying the pattern Flight time was shortest with 3 Blade at 12 minutes, on average 14 minutes on 16oz.
Sound measurements as measured by distance and Db
N/A
Comments:
Although the RPM's might look the same as the OS-1.40, the performance on all but the 17x12 was much better. The plane was an Angels Shadow #1 at 4.95 KG..