jeffie8696

Picked this engine up new old stock. After a proper break in it really impressed me. On Sig 15% nitro 20% castor and an 8X4 Master Airscrew with an OS A3 plug it turned low 15,000 s

Ernie Misner

Wow, neat old engine. What year were they made I wonder?

Ernie

jeffie8696

I don't really know. Maybe the late 70s. Perhaps some of our fellow members have more insight.

Ernie Misner

Can you look through the exhaust port or glow plug hole and see the baffle on the top of the piston?

Ernie

jeffie8696

Yup.

jamesroutledge

I had one exactly the same, bought new in the shop in November 1980.

1QwkSport2.5r

Found a used one of these engines on eBay... I'm not keen on used engines but after reading this thread, is it worth buying?

aspeed

Maybe it is ok. I have a newer Schnuerle TT GP.15 that doesn't go that good. Couldn't even get 13,500 out of it. (7-5 prop) I was thinking maybe the boost port wasn't working because maybe the piston hole wasn't letting it get by. My .10 GP TT is a slug too. Is yours ball bearing? Looks like it.

1QwkSport2.5r

I'm going to swap out the FP .10 I have for either a TT .15 Looper or a ST X.11 Schnuerle blue head in my trainer. I should be able to get either pretty cheap. Who knows, I might buy both. The TT is bushed I think and the X11 SuperTigre is ball raced in the rear only. My flying buddy will trade me my FP .10 and ST G2300 for something else.

aspeed

If you need a .15, the LA is hard to beat. Better than the TT .15 and .10 that I have. The Supertiger .11 sounds good. My opinion, it is free. I also had an older TT .25 that was not too great either. Only TT's I liked are the .40s and up.

1QwkSport2.5r

I am not an OS guy. I own the FP .10 because I got it dirt cheap at an estate sale. Aside from that I'd not have it. My flying buddy has a diesel head for it and likely will convert it to diesel. I would rather have the old stuff nobody else (or almost nobody else) has. I mean, who flies a loop charged/scavenged engine in a trainer? Nobody at the clubs I'll be flying at... Nobody around here runs SuperTigre. If I could get an Enya .11CX AAC, that would be my first choice. These other two options are cheapie throw-aways should I crash hard enough. I don't think my trainer could handle anything more powerful anyway. It's a rudder only plane.

aspeed

Ya, rudder only can't have too much power anyway. My TT .10 could barely take off in my field. It was a bit heavy with the standard servos of the day, and needed bigger wheels to take off. Put in an FP .10 and a world of difference. The LA is a bit lighter and a bit more power again, marginally. I kind of get tired of the OS fan stories too, but they refined the designs down to an art there.

1QwkSport2.5r

Without getting into it too much, OS' strongest suit is marketing. Secondly, they make an engine so anybody can fire it up, run it, and not destroy it in 3 runs. They have great Carburetors which allows the more novice users to adjust the engine easier. But the same can be said for Thunder Tiger. With most of today's sport engines, it's take it out of the box, mount on a plane, and go fly it. The better quality engines will require a little more skill and time to properly break in the engine. I am not saying OS doesn't make a quality engine per sé, I am just saying I have higher standards and OS doesn't meet those standards. But back to the topic... The little TT .15 has a few days left at auction and no bids. The Super Tigre X11 has about 6hrs left. I'll try to nab both if I can. They're both at a pretty low price right now. Right now the smallest engine I own besides the FP .10 is an ST S29 and I wouldn't mind getting a few of the smaller engines and obscure isn't out of the question for me. I like weird and uncommon.

aspeed

I seem to have a lot of the weird uncommon little stuff. The Supertiger .11 looks like a nice addition. I wouldn't mind one of those myself, but really, how many more little guys do I need. I hardly fly with them any more now that I seem to have moved to the windiest place on earth. There is a Novarossi .09 around too. Looks kind of old timey cool. I noticed they are out of stock, wonder if they will keep getting them? Planet Hobby.

1QwkSport2.5r

For some reason, when I got into collecting aircraft engines I knew early on I wanted to have the stuff most other people won't or don't even know exist. Granted, most of my engines are relatively common and well known, but I'd love to see the looks on peoples faces when I show up to the flying field with a Super Tigre or Enya that runs flawless. My buddies' field is pretty much 100% OS for 2-strokes and Saito 4-strokes. That isn't to say I'll fly there exclusively but I guess I like to show people up that turn their nose up at stuff other than what's "the best". I'm excited to fly my big foam target drone with a K&B sportster .65.

jamesroutledge

Perhaps it will be of some help to someone in the future.
Magazine advert for the earlier model with metal carb. RCM July 1978.

aspeed

"Shopping by mail is fun and easy." I like that. Things have changed a bit since then, for the better, I guess? Click

Nitrovein

I actually have that .20 RC, first glow engine I ever bought as a kid, was in the mid 80's sometime.
Maybe I should let it howl a little again some day soon...

1QwkSport2.5r

I gave away the .25 I had. Low power and poor carburetor, weak conrod. Good for display. The modern TT iterations are better made - the old ones were made by Magnum for Hobby Shack.

aspeed

Correct me if I am wrong, but Magnum bought from TTiger long ago. It then changed over to ASP/Sanye. It never really made motors AFAIK. I have never had a good TTiger below the .40 size. The crank fit was too tight or way too loose, and there was no power compared to others in their time period. I have the .07s, .10 and .15s that were duds. The Magnums from Taiwan were TTIger, and the other newer ones were Chinese ASP Sanye or SC.

Nitrovein

I believe you're right aspeed, at least that's what I've heard as well. I think it was a couple of years after I bought mine that Magnum appeared and they looked like the TT that was sold then.

The carb is a nightmare, one click on the HSN in either direction and it's either lean or rich!

1QwkSport2.5r

My TT .25 carb behaved similarly - the transition from idle to WOT was sloggy and slow even with the idle set as perfect as I could get (I could get a 2000rpm idle with a 9x5 on 5% nitro) but it was just a slug both in manners and power. Mine was twin ballraced and had a Meehanite piston/steel liner. Piston seal was very very good...

It was advised not to run it real fast and not with a lot of nitro if you wanted it to last at all.

Nitrovein

Yes the seal was good between piston/sleeve, but not at the crank... It sprayed fuel like crazy from the crank.
I also believe that rpm should be kept to a minimum, if I recall right a 9x4 was recommended.
I did run it with pipe, but the rpm increase was waaay beyond anything healthy for that engine.
I had planed to use it in a boat and did convert it, but it was only tested in a tub. Never got around to using it for anything...

buzzard bait

My TT .25 Pro was quite a good engine on the test stand. It looked to be almost a OS 25 FSR clone; power was a little better, but only because it had a less restrictive muffler; somebody really wanted one so I sold it to him.

1QwkSport2.5r

The TT Pro series were the modern Schnürle scavenged engines. The TT .25 we were speaking of back in this thread was the hobby shack version - made by the then Magnum engine company. They were terrible engines with poor carburetors and weak rods. The newer TT engines were made by Thunder Tiger themselves and far better engines.