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-   -   OS vs. Super Tigre engine (http://www.rcuniverse.com/forum/questions-answers-154/11261504-os-vs-super-tigre-engine.html)

devil505 10-13-2012 03:36 PM

OS vs. Super Tigre engine
I currently have a Super Tigre 45 ABC in my great planes cherokee. The plane flies good but the motor has always given me little fits every now and then. I have found a used OS 46 FX motor, just wondering what your thoughts are about which motor is better, thanks

jetmech05 10-13-2012 04:46 PM

RE: OS vs. Super Tigre engine
I have always used OS or Siato for glow engines.....I have had pretty reailable operation from them...Never have I run a Super Tiger

alan0899 10-13-2012 05:07 PM

RE: OS vs. Super Tigre engine
G'day Mate,
I only ever had 1 Super Tigre, it was a 61 ringed, & it was the WORST engine I have ever had.
I used it in a plane for my instructors course, in 2004, & I had lots of dead stick practise.
I was Chinese made & absolutely hopeless.
I went with OS before, & after, & have never had trouble since.
Just my opinion.
For what it's worth, but it sounds like you need to experience OS for yourself, & make up your own mind.
PS, Super Tigre don't like nitro.
I run all my OS engines with 10% nitro & 18% coolpower oil. NO castor.


da Rock 10-13-2012 05:13 PM

RE: OS vs. Super Tigre engine
IIRC, Perry Carbs stayed in business for years mostly thanks to Super Tigre. I'd look around for a replacement carb before I'd scrap the sucker. The control line Tigres were awesome. And the few RC that I've noticed had had their carbs adjusted correctly and ran excellent.

devil505 10-13-2012 05:17 PM

RE: OS vs. Super Tigre engine
The motor is on its second carb. Everyone at my field flies OS or saito. I have had this motor for 4 years and have had alot of dead sticks with it because as I fly after each run I have to readjust the carb either richer or leaner depending on what it wants. Just seams as though it is a fussy motor where as the OS is more reliable.

JohnBuckner 10-13-2012 05:30 PM

RE: OS vs. Super Tigre engine
Well fact be know your experiance with the ST is not really unique. If you want a complete revelation in how good an engine can be the for that airplane then try an OS 55AX or the new series 11 46AX.

I have many of the AX's and they will provide a completely different experiance in terms of user friendliness, reliability and good throttling (they shine in the throttling).

I have used various ST in the past but not any more. Now the FX series was formerly my favorites before the AX's so if you have one I would definately use that over an ST.

Do be aware, oh maybe ten years ago there was a bad run of cylinder plating on the old OS.46FX but they got that fixed pretty quick so when buying a used one be carefull inspect the cylinder sleeve for any sign of peeling.


jester_s1 10-13-2012 06:11 PM

RE: OS vs. Super Tigre engine
The OS will be more powerful and easier to tune, and likely more reliable if you tune it right. ST's can be good runners too once you learn their quirks and make sure there are no air leaks. I can tell you from the two I've had that needle valve settings should be fairly straightforward. If they are really inconsistent, look for air leaks in either the engine or the fuel lines. ST's are known for having a rich midrange, but that can be fixed by rotating the spraybar slightly.

blvdbuzzard 10-13-2012 07:43 PM

RE: OS vs. Super Tigre engine
I have learned how to tune the ST's. They are unique in how they like to be tuned. As stated, any air leak will have you chasing your tail. I have gone though (3) OS FX series engines yet my ST 45 is still running. I have flown a few of the newer ST's. They seemed to be the same with a slightly better mid range. I found that STs do not need or really like high nitro fuel. They can be picky about the props they run. One hated any Zinger I mounted on it. Yet it ran great with a Master Air Screw. Never did get one to run with an APC. Fuel tank position is really critical too. I have side mounted the engine to get the carb and fuel tank center lines to match up.

One trick it to look and the cats eye under magnification to see if there is any burr causing a problem. I can not remember the drill size off the top of my head.


jester_s1 10-13-2012 08:00 PM

RE: OS vs. Super Tigre engine
True, the ringed Super Tigre engines last forever. An ABC engine will lose compression and maybe peel eventually, but a ringed engine will almost never wear out if it's taken care of properly.

OliverJacob 10-13-2012 09:11 PM

RE: OS vs. Super Tigre engine
I just sold a very low time Italian made ST 61 and I sometimes wish I had kept it.
This one started very easy, had plenty of power and no dead sticks at all.
It was a little on the heavy side, with the huge stock muffler it won't fit into most cowlings.

I also have 2 OS 46 FX, one with a muffler and one with tuned pipe. Great engines, no problems, no dead sticks.
One thing - I never measured it, but I could swear the FX use more fuel then the ST 61.

So I do not know about the Chinese made Super Tigres, but my Italian one ran great.
I'd get another one, if the weight and size is not a problem.

HighPlains 10-13-2012 09:28 PM

RE: OS vs. Super Tigre engine
The OS engines have slightly milder timing and are easier to tune. The Tigres have slightly more power. I've run them mostly on 15% fuel over the years, but have also run from 5% to 25% (and 65% on racing X-40's). The best Tigres were from the World engine days, before the cheap castings were used for the head and drive washers. Moving the production to China did not make much difference. When set up properly with good tank position, and right plug, Tigres have a lovely gurgling sound at low power when you are coming in for a landing.

JohnBuckner 10-13-2012 10:47 PM

RE: OS vs. Super Tigre engine
Engines with mufflers that can easily be mistaken for a six inch cast iron water main just never appealed to me. Hmm I do still have my old .23's and I did love those. Oh my I just figured out how long its been since I ran em', forget it I don,t wanna think about that no more:D

NoOneFlysAtMyClub 10-13-2012 10:52 PM

RE: OS vs. Super Tigre engine
Set up properly, they are the most reliable engines you can buy.
And as a bonus, the ringed engines will last forever if you take care of them!

jaka 10-14-2012 03:55 AM

RE: OS vs. Super Tigre engine
All engines today are good! The Super Tigre too...if you treat it right and don't mess with changing carbs and run the wrong fuel or running too lean.
But the OS AX series are slightly better though,more userfriendly and more powerful.

Did you change the stock Super-Tigre carb for a Pery? Why? The Perry is very sensitive to dust/particles as it has a thin slot that meters the in-comming fuel to the carb. Othervise it's good but not as userfriendly as modern Super Tigre or OS carbs.

franklin_m 10-14-2012 05:18 AM

RE: OS vs. Super Tigre engine
I've gradually moved away from OS engines in favor of ST. Perhaps I've had good luck with them, but I find them more reliable and able to swing a wider range of props. No kidding, I let a ST 45 (ABC) idle for five minutes (timed) then full power w/o hesitation. I've had fewer deadsticks. Getting them tuned can be more challenging, but once there, I've found them very reliable.

Stickbuilder 10-14-2012 05:53 AM

RE: OS vs. Super Tigre engine
I've owned several of each over the years. One of my favorite engines is the ST .90. It is stone reliable and starts and runs easily and consistently. I also have owned several of the OS engines, but never one of the small (.40) size models. If your wallet will stand it, I'd go for an OS 4 stroke engine. Just my opinion.

Bill, Waco Brother #1

ARUP 10-14-2012 06:46 AM

RE: OS vs. Super Tigre engine
I have had good luck with ST engines. Read the instructions for initial carb set up. The key is getting the high and low needle ends inside the spray bar the proper distance from each other. When you turn one 'in' you will have to turn the other one 'out'. Adjust for max slightly rich rpm. Then slowly try to reduce throttle. If rich then close low speed needle some and open high speed needle same amount and recheck. Vice-versa for lean condition. Recheck high speed setting again then repeat the exercise. Takes a little time but works. I always run 10% nitro and used the muffler pressure for tank. Make sure the fittings aren't clogged.

OldScaleGuy 10-14-2012 07:04 AM

RE: OS vs. Super Tigre engine
O.S. for 2 strokes and Saito for 4 stroke engines. They do cost more but like everything else, you get what you pay for.

Sentinel 10-14-2012 07:10 AM

RE: OS vs. Super Tigre engine
I love my ST's once you get them set up which can be a headache sometimes.

But once you do leave it alone, my 75 & 90's you can't beat for power.

But just like engines of all kinds some people have there favorites, whatever your pleasure that makes you happy.

I guess it's all in the eye of the beholder.

bigedmustafa 10-14-2012 08:04 AM

RE: OS vs. Super Tigre engine
Super Tigre engines can be very powerful and very reliable; this is true of the newer Chinese-made (GMS) Super Tigres as well as the Italian-made examples. Many engine "experts" at our local club only run O.S. 2-strokes and don't know the first thing about tuning any other brand of glow engine.

Comparing the ST GS-45 to the O.S. .46 AX:

Compression: O.S. is lower compression, so it is less sensitive to precise tuning. ST higher compression makes smaller needle adjustments more important

Break In: O.S. has soft nickel liner that allows for reliable idle right from the box, harder ST piston liner may require a bit longer to break in

Prop Range: O.S is tuned for torque and turning larger props, ST is designed for higher rpms and won't perform as well with larger props (11x7 APC for example)

Fuel Requiremens: O.S. will run great on 15% nitro as lower compression and more nitro help with tuning flexibility, ST designed for low nitro and will run better on 5% or 10% nitro than 15%

Glow Plug Requirements: O.S. will like hotter plug like (O.S. 6 or 8) due to lower compression, ST doesn't need hot plug and runs well on medium hot like O.S. No. 8 or Fox RC Long plug

The reason that so many pilots rave about O.S. Max 2-strokes and complain about Super Tigre engines is simple, they set both engines up to run like an O.S. 2-stroke and only the O.S. engine runs well. If you put an O.S. #6 plug and 15% nitro fuel through a ST GS-45 and try to turn an APC 11x7 prop with it, you'll never get it running right. An O.S.Max .46 AX will run all day long with that setup and hardly even hiccup.

The converse is also true, however. If you set up a ST GS-45 with a Fox RC Long glow plug and 5% nitro fuel and have it spinning an APC 10x7 prop, it will run all day long with barely a hiccup. The O.S. .46 AX would also run on this setup, but it would be significantly down on power and prone to dead sticking at idle with the low nitro and medium hot plug.

A Volkswagon Jetta TDI is faster than a Porsche 911 when you fill them both up with diesel fuel.

O.S. Max makes terrific engines; perhaps more importantly they make really, really fine carburetors. I've never tried talking anyone out of buying an O.S. Max engine. If you truly understand how to set up and tune glow engines in a general sense, however, you can run most any brand of engine you'd like and enjoy similar power and reliability for half the price. There are two kinds of pilots who fly glow engines, pilots who will only fly O.S. Max and pilots who actually know how to set up and tune a glow engine.

jessbree 10-14-2012 08:04 AM

RE: OS vs. Super Tigre engine
i have had both os and super tigre engines and thunder tg as well and out of the three i love my super tigre by far. they have been so easy to tune and have been so reliable and have always started rite up every time.im not knocking os or thungertiger at all they are good engines as well but it seems that my super tigres are a bit more powerful and the sound the super tigre makes at idle is perfect. i cant see myself flying anything els but super tigres. also factor in the price difference and you cant go wrong. i hope this is helpful.

Quikturn 10-14-2012 08:44 AM

RE: OS vs. Super Tigre engine
To the OP, both engines are fine engines. You probably do have an air leak issue if you are experiencing erratic behavior. Areas to check would be the carb to engine o ring, HS needle valve o ring and rear cover gasket. Also, make sure your carb is clean.

OS engines are easier to tune but the ST will run just a good once properly tuned. Keep in mind the ST engine has a high, low and mid range adjustment. High and low are set by needles and the mid range is set by rotating the spray bar. Generally, you leave the mid range adjustment alone unless there is a need to adjust it.

Super Tigre engines are a European design (i.e. Super Tigre, Rossi, Webra) and as such are designed for lower nitro due to the cost over there. 5% fuel is all it needs and it's cheaper too. I keep 15% fuel for my OS's and 5% for my ST's.

I was strictly an OS guy (love the FSR's and SF's) until a few years ago. I decided to try other brands after hearing about the FX liner peeling issue. I've since run ST, Webra and Rossi and like them all.

RCPAUL 10-14-2012 08:46 AM

RE: OS vs. Super Tigre engine
There are some people that cannot even tune a radio. I have a friend that in 20 years never learned how to handle any engine. He just gave me 3 STs and a Fox and has gone electric. I love my STs.


kochj 10-14-2012 11:19 AM

RE: OS vs. Super Tigre engine
I almost didn't click on this post but glad I did...

I have 2-ST engines ( a .51 and a .91) and have done okay..with them)
However... The .51 had a tuned pipe setup on a reactor (I say had, becuase it would quit around half a tank, and the dead stick muffed the plane up and I have not fixed it yet.
It had a 12.3.456464 or a 11x6 apc ... can't remeber exactly... ran on 10-15%... .perhaps that was the issue...

The .90 had a after market muffler, was on a piper cub and it ran fairly well, but deadsticked on takeoff, nosed in on pavement....
I switched over to a .91 magnum 4-storke....

I had a .46FX OS that I ran and ran and ran, and then sold it....
It was my 1st engine I ever had, and first rc plane I ever had flown....
It was a SuperTiger seamaster float plane....
I even flew that plane when it was raining.... It NEVER deadsticked...and was a set and forget type engine....
This was on the stock muffler though....

I have a OS 1.20 AX that ran great on the stock muffler, but dead sticked and flung props when hovering and loaded on flat, and leaned out when going up....
This was with a tuned pipe.....

I vote for the OS .46fx as it has a centimental value and ran perfect....
I will not give up on ST engines, but the information on this post would help me, and I bet, allow me to tune them properly....

OS is a set and forget engine... that would work great...

skippyc5 10-14-2012 11:27 AM

RE: OS vs. Super Tigre engine
Quick and simple answer. OS hands down. a very good running, reliable engine that i have used for years.

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