Hi -
I just purchased an Alpha 60 ART airplane. This plane has a 72" wingspan and the manufacturer recommends a 60 engine

I can buy an SK 80
OS tigre 60
or an OS 60

which would be best? how do you feel about SK engines?

are they good?

No choice at all buy the OS! SK- maybe ok and maybe not, some run ok but I have seen (not heard about), actually seen and used some that were ok but a couple of others had to have the carb replaced to run half way reliably. The Super Tigres need a lot of breakin and the carbs can require a lot of fiddling with to run right. The OS will normally be close right out of the box and they are very easy to tune and will last a long time. Thunder Tigers are another good choice.
IMHO
Fred

I can't speak for the other brands, but I can tell you you won't be disappointed with OS Engines.

the guy is selling all these used, so no break in issues.

but what about the power difference. you think the OS60 would still be better that the SK80?

I have no clue about this :-)

Personally, I keep stumbling across 'great deals' on used engines, but I can't bring myself around to buying one. Not only is there the issue of the condition of the engine, there's also the lack of warranty/support. There are some decent .60 size engines out there for under $100, and I think I'd be inclined to go with one of those.

These are my own personal thoughts, and I'm sure many people have had good luck with used engines. Headaches and dead sticks are just some things that I like to avoid at all costs.

If the SK80 runs good ,it well be stronger running than the OS 60. However , if you have a very light mechanical background , go with an O.S.75 . an not the .60 . You`ll find the .75 very useful in about any .60 size plane and if you did decide to sell it down the road , it well be more sought after . I highly recommend going with an O.S engine if this is your first one .
If your new to flying ,your odds of having trouble with a used engine are very likely , but there is an upside , you`ll learn deadsticks really fast .

OS Tiger = Super Tigre?

SK Engines are distributed by KangkeUSA. They have a good reputation as solid performers and Kangke can be contacted for spare parts and warranty support if needed at http://www.kangkeusa.com.

Super Tigre engines are very strong runners, and they are supported by Hobby Services here in North America. Hobby Services is Hobbico's service and warranty arm, and they're the same folks who provide service and warranty support for O.S. Max engines.

Any of the three will fly the Alpha .60 very well. If you have your choice of the three, however, you should take the O.S. Max engine for the simple reason that it will have a higher resale/trade value down the road.

ok...even if the OS has a little bit more use than the SK?

I am still wondering something.... why is the SK harder to tune that the OS?

It's not. OS makes good engines, so do a lot of others. I've had an SK 50 for about a year, I have owned several OS and Super Tigre engines over the years. They are all good. 2 stroke glow engines are very simple devices, and most people can use them effectively with little effort. Some can't.

thanks Jim!

this freaking hobby got the addictive personality in me out !!

This is going on a Alpha 60 72" by H9 - i'm - so I want to put the big engine on it. I just wanted to hear someone say SOMETHING about the SK engine - I am very new to this and one thing I know is that OS' are solid....

what I really want to hear is not the comparison between OS and SK....is the performance of the SK...you know? -

thanks everyone!

I'd second what Jim said.

I'm not personally familiar with the SK .80, but by reputation they are powerful, reliable, and are especially designed for higher torque rather than higher rpms. I'm told they're not screaming fast racing engines, they're more designed for turning larger props well. I'd expect the SK .80 to turn a 14x6 or 14x7 prop strongly.

Your Alpha .60 trainer would fly quite well with any decent .46 ball bearing 2-stroke on the nose. Not only would the power of the SK .80 not be needed on the Alpha .60, but the nose clearance of the airframe would make installing the proper propeller for the SK .80 a challenge.

I have a Super Tigre G-61 on my Sig King Kobra. It's fairly heavy, 26.8 ounces w/ muffler according to Tower, and it spins speed props really, really fast. I have a Master Airscrew S2 Scimitar 11x7 prop turning around 13,500 rpms on it. The Super Tigres aren't known for turning larger props well, although the mileage seems to vary greatly in this regard. I haven't tried a larger prop on mine yet, it's broken in but doesn't have too many hours of run time yet, so I haven't experimented with it.

The O.S. Max .61 FX is known as a fairly anemic .61 2-stroke, but it's a really good fit for the Alpha .60. It weighs almost a quarter of a pound less than the Super Tigre G-61 at 23.6 ounces with muffler. It will turn a 12x5 or 12x6 2-blade prop efficiently, good sizes for an Alpha .60 trainer. It's reliable, it's easy to find parts for it, and while it may not be a powerhouse, it will also fly the Alpha .60 really well with plenty of performance.

All three of the engines you've been offered are terrific. The O.S. Max .61 FX is simply the best fit of the three.

Hey thanks bigedmustafa -

I have two OS 46 - and one of the has a long tunepipe. I was thinking about putting this one on the alpha60 but the guy told me it's not enough power.

so, would the SK 80 be too much power? or can I fly it with it?

or should I just install the OS.46 with the tune Pipe?

A .46 FX or AX would be plenty of power for the Alpha .60 trainer. A plain bearing .46 like the .46 LA probably wouldn't be enough power. Which model do you have? Also, I'm describing "plenty of power" as smooth easy take-offs, basic loop and roll aerobatics, and flying on the wing.

Also, engines with tuned pipes tend to be an all-or-nothing kind of power source. By definition, tuned pipes are tuned to provide improved performance at wide-open throttle (WOT). If you're not flying at WOT, then an engine with a tuned pipe will tend to run sporadically at partial throttle.

If you have an O.S. Max .61 FX, or can get one with the Alpha .60, then I still say it's the best fit for the Alpha .60. If you have a .46 FX or .46 AX and you're looking for gentle trainer-like flying with mild aerobatics, then this would be a good combination with a standard sport muffler.

If you don't mind some extra nose weight and you really want to wring out the maximum performance of the Alpha .60 airframe, then the Super Tigre .61 or SK .80 would be good choices. You will probably want to try a 13x6 or larger prop on the SK .80 for it to run in it's ideal power band, and if the Alpha .60 doesn't have the ground clearance for such a long prop diameter, you can either buy larger diameter wheels for the airframe, try a 12x6 or 12x8 3 bladed prop (similar in load to a 13x6 or 13x7 2 blade), or both.

If you're going to buy a new engine to put on an Alpha .60 trainer and you want a good combination of power and economy, I'd look at a plain bearing .61 like the O.S. Max .65 LA, the Thunder Tiger GP-61, or the K&B Sportster .65 available from http://www.mecoa.com . These powerful, inexpensive engines will provide very good power and light weight. If you decide to put your Alpha .60 on floats later on and fly it from water (a common fate for many trainer airframes), these engines have no ball bearings to rust if they accidently get dipped in the lake.

The O.S. Max .65 LA actually outturns the .61 FX on a number of props, yet it weighs about the same as the .46 FX or .46 AX. Light weight translates into light wingloading and better glide ratio, which is a good thing on a trainer like the Alpha .60 ARF. The only downside to plain bearing engines like the .65 LA, the GP-61, or the Sportster .65 is that they run best on fuel with plenty of castor oil as part of the lubrication package. If your local hobby store only sells fuel with 100% synthetic oil, you're going to get weak performance and premature wear. Ball bearing engines are generally heavier, but they're less picky about the kind of lubrication with which you run them.

Hopefully, if I haven't gotten any other idea across to you, at least by now you should have a pretty good idea that the Alpha .60 ARF will fly quite well on a wide variety of engines and that which engine in particular that you choose isn't critically important. Rather, each engine represents a trade-off in terms of weight, wing loading, fuel consumption, and price. If you go with an engine at the top end of the size and power scale like the SK .80, you may need to upgrade your wheels and props to assure it runs the best that it can.

Good shopping and good luck!