mvigod

For immediate release:
**O.S. ENGINES 56FS “a” SERIES 4-STROKE ENGINE

A big performance boost for 40-size planes!
In addition to less noise, the muffler features a multi-positional manifold with a rubber Oring
that helps prevent oil leakage. The 40NA carburetor is equipped with a venturi that
reduces the chance of fuel leaking out onto the cowl, while also creating more positive
air/fuel flow!

• Mounts with no-mod ease in the same space as the FS-52.
• A newly designed lubrication system eliminates the need for crankcase
ventilation.
Specifications:
• Displacement: 0.569 cu in (9.32 cc) • Bore: 0.945 in (24.0 mm) • Stroke: 0.811 in (20.6
mm) • Weight w/muffler: 16.26 oz (461 g) • Practical rpm range: 2400-13,000 • Output:
1.0 ps @ 10,000 rpm • Includes: 40NA carburetor, muffler

OSMG0956 56FS “a” Series 4-Stroke Engine Retail:$399.99 Street:$249.99
IN STOCK: Late June

For more information please visit: www.osengines.com

wcmorrison

My Feedback: (2)

Does this mean OS has caught up with Magnum by using Positive Crankcase Ventalation, feeding the crankcase vent to the intake manifold? Well Duh! About time.

Cheers,

Chip

yank51

Well, wondered when they would anounce it... Check out my earlier thread here: http://www.rcuniverse.com/forum/m_5798973/tm.htm

BTW, didn't actually see this on their web site, but I'm sure it'll get there..

Ken6PPC

I thought somebody said OS was going to produce lighter engines! This new 56a weighs a full ounce more than the 52, muffler included. 16.26 oz for 56a vs. 15.2 oz for 52.

If you look at the muffler and cylinder head, I bet you can figure out where that extra ounce came from. It looks like they stuck a 2 stroke muffler on it! What was OS THINKING?

This is disheartening. I would love it if OS could shave off some weight, and increase their power output. Guess I'm going to have to keep buying Saitos. (2 OS FS & 4 Saitos - so far...)

NM2K

My Feedback: (14)

It sure looks that way, doesn't it?

This reminds me of the OS FS-70 Surpass II. It is heavier than the original it replaced. Makes no sense.

That's okay, I just picked up a brand new Magnum .70 four-stroke off eBay for $105.00. I've been wanting to give one a chance and now I have the opportunity. Don't know why. I've got a bunch of other brand engines in this size range already. I've had a bunch of Magnum two and four-strokes. All have served me well.


Ed Cregger

oceansfiftyseven

$250.00 for a .56? Yikes! No thanks. I too shall stay with my Saito's.

Hobbsy

My Feedback: (102)

Overweight and ugly, what a combo.

Ken6PPC

Hey! I resent that......

yank51

Well, let's see... 28.5 grams (1 oz.), in a plane the size that an engine of this size would fly, no.... don't think it matters now does it??
Well, ugly?? I guess beauty is in the eyes of the beholder is the saying I learned as a kid.... (in other words, to each there own, eh??) I basically think OS engines look far better than the Saito brand, with the exception of the Golden Knight series which is nice looking, but then, I guess that's just my opinion right?? Kind of the Ford vs. Chevy argument all over again is it not??
Why is it when something about the new OS engines comes out, do the same people come and try and make it negative?? How about we wait and hear from those who have bought one and used it, to see what they have to say... Sounds like a good idea to me, does it not? How about any of you out there, especially from the areas of the world where this engine has been being used? All the Saito guys are "trolling", is it (this new OS) really a good engine?
Oh, the looks again, it's ugly...LOL Wait, I can't even see much of mine, it's buried in the cowling with only the valve cover sticking out... What color do you want to see sticking out? Blue?? Black?? Gold?? You make the choice...

Ken6PPC

EVERY ounce matters! Don't think that it doesn't. It matters less when you are talking about a larger plane, but a .56 was never intended for a 90-size plane or larger. It is for a 40-size plane. (or smaller) Percentage-wise, one ounce of additonal weight on an engine this size is WAY more significant than if we were talking about large engines. AND - this comes about at a time when weights commonly get lighter on new engines - NOT heavier!

I don't have anything against OS personally. No axe to grind here - I have never had a problem with any of my OS engines. Like I wrote earlier, I have 2 OS 4s and 1 OS 2s engines, and I like them. I like them a lot. However, the 4s ARE heavier than corresponding models offered by Saito, and I have been buying more Saitos for that reason. Personally, I would LOVE to see some good ole-fashioned competition between OS and Saito to get weight down and power higher. All of us would benefit from that competition!

However, according to OS's own specifications, this new .56 OS FS engine IS heavier than the one it replaces. It has an UGLY 2s-style muffler, and the price has gone way up. (I want to see you hide that muffler under your 40-size cowl!) You are correct in saying that beauty is in the eye of the beholder, but does ANYONE really like the way a large 2s muffler looks?

Take a look at the two mufflers, one from the OS 52 FS and one from the OS 56 FS, and tell me which one looks better to you!



Lastly, I am certainly no "troll". Do you even know what that word means? It is very degrading to call someone that, and I don't appreciate it at all. Don't insult people, merely because they may not share your views.

blw

My Feedback: (3)

We can keep going if we keep calm about the differing opinions. This has been an interesting thread, so let's not ruin it. I think everyone does have to admit that the styling is a bit of a surprise.

I have some Evolution 2 strokes, and I've been told they are ugly. I'm not sure I agree with that but it doesn't matter. I think they are great engines at great prices.

A fair comparison looks like it is .75 oz heavier than the Saito .56. If we can believe the street price of $250 then it is going to be something like $55 more than the Saito. Manufacturer HP figures are meaningless, but OS is rating this at 1000 more RPMs over the Saito.

NM2K

My Feedback: (14)

---------------


That's me! <G>


Ed Cregger

pc55bomber

IMHO making engines lighter can be a disadvantage.
I would rather use a heavy engine and not have to add lead to balance.
I used an OS91FS11 in my Tiger moth simply because the Saito 91 was too light and I would have to add lead.
OK no big deal you say, but think of it this way, engines get lighter and lighter, you end up with a powerful lightweight engine with no durability and breaks easy when crashed.

Look at the ocean going racing yachts, make them lighter, make them lighter, make them with carbon fibre ........
"What was the loud cracking sound", Oh just the boat breaking in half and sinking in record time.

I like quality engines with longevity and durability, remember with anything, there is a tradeoff.

Hobbsy

My Feedback: (102)

Yank, while I may not like its looks, I also know it will most likely run like a Swiss watch.

yank51

My public apologies for that one Ken, sorry....

I don't want to turn this into a Ford vs. Chevy discussion either. I am hoping to see people post who have actually used one, to see what they have to say.
As far as the weight, with the type of general flying I do, that extra oz. means less weight I have to add to balance out my plane for the proper CG is all. I'm not a "hang it on the prop" type of flyer, where that oz. is much more critical (but, as I said, you are going to probably have to add weight anyway, so....)
The mufflers... Well, I"m not sure what they are up to with that one, but it seems there is some design change in there that they want to explore.
And, like Hobbsy said, it'll probably run like a Swiss watch, which my OS 70 Surpass II does, plain and simple. As an interesting side note, I place this 70 on a Hanger 9 Alpha 60 plane in place of the Evolution 60 that comes with it, and it's made a SUPER model to teach my son to fly on. Great response, idles like a dream, a really god match. Sure, a Saito 70 series could have gone in there, and I'm sure it would run just fine, but I'm partial to the OS line is all.
The only negative that I'd have right now is the cost of this new OS, and I'm sure that will change when the discounters get in there...

Ken6PPC

Thank you. Apology accepted.

My main point is that I don't think OS "gets" what we need and want. Lighter, more powerful, durable, and if possible, less expensive. (And, I'm not certain that last one really makes much difference if you nail the first three....) Asthetically pleasing would be nice, but as you said earlier, that's in the eye of the beholder. So, I wouldn't worry all that much about looks if I were OS.

OS had a chance to make some real improvements to this size engine, and I think they missed the mark. I also admit that I am basing this ONLY on pictures and specs. I haven't even seen one IRL yet, much less had personal experience with it, so I reserve the right to change my mind. I hope I do!

liquid_TR

I dont like summoning old threads in forums, but would really like to hear others 56 FS experiences, problems, etc..

Ive been using mine for about a month now, and its power output is really impressive compared to 52 surpass or 62 saito. MA 3 blade 11x7 @ 11500+ RPM, APC 13x6 @ 10300+ RPM no lag, instant spool-up!

Runs like a swiss watch, never misses a beat, jaw dropping idle, no dead sticks what so ever. I was reluctant to buy one bacause of the price, but i was really curious about this new series of OS alpha engines. The new lubrication system works like a charm, no goo, oil or any kind of mess on the plane after flying for 5-6 times a day, and plenty of oil in the front bearing & under valve cover.

Only problem ive encountered is; I wont be using my engines for about 2-3 months and would like to put ATF dexronII in my 56. (long term storage procedure) I dont use ATF during the season as i use all my engines at least twice a week. But for long term, with my saitos I normally do this thru using the vent like, i drench them with ATF if I wont be using them for a long period of time. OS 56a has no vent line, and using carb is useless as its a 4-stroke engine. the only option really is pulling out the rear engine cover and pouring ATF. But this engine has a "sealed" bearing at the rear..

you get the picture... any ideas??

Harry Lagman

Liquid, thanks for the tach numbers.

10,300 rpm with an APC 13 x 6 is a very impressive number. That's more typical of a .70 four-stroke.

Have you got comparative numbers for the .52 Surpass or .62 Saito? Have you run the same prop on all three as a comparison?

the pope

I to was curios about putting after run oil into the 56 what does the instructions say in regards to this predicament? Cheers the pope

blw

My Feedback: (3)

The APC 13x6 is one of those props that seems to turn high numbers when compared to others in the APC line. I once ran an APC 12x6 on a Saito .72, yet gained about 1000 RPM when moving up to the 13x6.

newguy05

My Feedback: (2)

i just won one of these from a fun fly, cant wait to replace my 46 ax with it, couple oz lighter and more power. wow 10,300 with apc 13X6, thats more than my supertigre 90 2stroke is getting.

Ken6PPC

Were you by any chance at Joyce Park this past weekend? If so, you won MY engine!

liquid_TR

my friends sweet sounding 52 pulls a APC 12x6 @ 9800 RPM on 10% omega, where as 56 pulls ~10500 RPM with 10%CP;
a saito 62a was tached at 9800 RPM on APC 13x6 with 15% nitro CP heli blend, where 56 managed to peak at 10300+ with 10% CP (havent tried 5 or 15% nitro).
For comparison, we also broke in a new YS63, ofcourse its in a different league, was pulling hard with a APC 13x6 @ 11600 RPM on 20/20 CP heli blend.

It is a pricey engine, no debate - but its worth a try if you want no mess on your plane with impressive fuel economy (getting 10 min run time on a 8 oz tank with about half full tank on landing on a fast warbird), VERY easy to tune engine at nearly the power of a 70 size four stroke without complicated plumbing.

I found a way to put ATF in the engine without disturbing the backplate gasket: thru valve cover. closed loop oiling system helps the pushrods to "drink" away the oil you put in the valve assembly straight down to camshaft and front bearing. Very effective if you are planning to put the engine away for 2-3 months. Weekly used 56 wouldnt need daily after run treatment anyway.

newguy05

My Feedback: (2)

Yea sorry bout that but i was at the 4 stroke rally this weekend. i won it for 3rd place spot landing.

newguy05

My Feedback: (2)

i wuz the kid that was flying the silver p-51 mustang with the blue rudder if you were there, nice flyin site btw.