Super Tigre G90
 

ST G90 - just run in
Cool Power 15%/Omega 15% Heli
MA Scimitar 13x6
Hot/Humid

10,500 RPM

RE: Super Tigre G90
 

Looks strange... ST G90 (made in Italia), STANDARD FAI fuel (80/20),
Master AirScrew 13x6 - 12100. Humid, +2 Celsius, 300 meters sea level.
After about 1 hour break-in (ringed ST need MUCH more brake-in ! About
4-5 hours, I think).

RE: Super Tigre G90
 

Klava ... mine is breaking in after 2.5 gallons, but cannot get more than 10,750 here. Oh well ... its too humid and hot.

RE: Super Tigre G90
 

After three break in tanks of Coolpower 10% fuel, and three flights, my ST .90 is turning around 10, 600 RPM with an APC 13 X 6, 3,000' ASL, 45 degrees, low humidity.

RE: Super Tigre G90
 

New ST 90. Running in befor Davis Diesel head conversion. 4 12oz tanks of Red Alert. Getting 12100rpm with APC 13x6, 12200 with
TF power point 13x6. 60deg F 52% humidity. I think it is going to be a keeper.

John.

RE: Super Tigre G90
 

ST G-90 (Used)
Bisson strap-on muffler
Powermaster 5%
Zinger 13x7
11.5K
1,500 ASL
75 deg.

RE: Super Tigre G90
 

Guys ... I need to move to somewhere cooler and less humid ... looks like in my country I lose about 20% performance!!!

RE: Super Tigre G90
 

ANother reading from this morning:

1,500 ASL
70 Deg.
5%
15x4 Zinger
9.9K

RE: Super Tigre G90
 

Guys since I found the Super Tigre .90 experts, I was wondering if my ST 90 could be dying on me because I am trying to run a 14 x 10.

I know I am crazy, but should I still ask if that is over propping ?
What's the largest prop run on one of these babies.

Thanks.

RE: Super Tigre G90
 

Cosmo - a 14x10 prop is something you want to run on a YS110, Saito 180 or some 120 sized 2C engine at the minimum. You will over load the G90 with such a coarse pitched prop. It can run on a 14x6 comfortably but a 14x10 is nuts.

RE: Super Tigre G90
 

I agree with the 14x6. Ran one on my hog bipe and no issues. 14x10 is just way too much prop for the engine.

RE: Super Tigre G90
 

The last Italian G90's had the round spray bar and were down about 500 rpm from one with the flat sided spray bar.

I changed to the Magnum/APC 108 carb. I get 11,000 with APC 14-6 with 10% fuel 30F 1,100'. It was 10,000 with the round spray bar carb.

Enjoy,

Jim

RE: Super Tigre G90
 

Does the chinese version ot the G90 have a different spray in the carb?? I have an italian version and I´m getting a lot of trouble with it since I bought it but it is probably because this engine had over heated a lot of times so I guess the ring is not round so it is loosing power or something else.

RE: Super Tigre G90
 

can anyone tell me how to adjust the spray bar on a g-90.

thanks starhop

RE: Super Tigre G90
 

Does Anyone Know What's Better A Super Tiger 90 OS 91 Or Saito 91 ?

RE: Super Tigre G90
 

The Super Tiger G-90 is somewhat flexible in the props it is able to swing. I use a 14-6 for sport flying but they do pretty well with 13-8 and 15-8's.

With the 15-8, mine will only do a little over 9,000. It pulls the prop and doesn't get hot but it is real slow to get up to speed and is a different animal compared with a 14-6.

Mine with a 13-6 sounds a little under propped? Turned 13500. Was instantly up to speed but seemed to be running too fast for a 90 size engine.

I have two of these engines. One is from around 1999 and the other was one of the last ones made in Italy. The last one had a 40 size carb on it and would only turn the 14-6 at 10,000.

I've a friend with a couple of OS 91's. His newer one was one of those that had a bad needle valve assembly, After he changed to a K&B needle valve, those problems went away.

On both the ST 90's and OS 91's, it is very important to use a aftermarket muffler actually designed for a 90 size engine. If you stick a 61 muffler or a J'tec pitts type muffler on one of these engines, it is going to run hot internally with all kinds of detonation problems. It's a matter of internal muffler volume, not back pressure.

I consider the ST to be better at pulling a too large prop but with 14-6 or 13-8, they are about the same.

I also have a couple of the Saito 91 engines. In a speed situation, the 2 cycle engines are much faster. In a 3D situation, the Saito 91 - 100 are much better.

Enjoy,

Jim

RE: Super Tigre G90
 

Italian made G90

5% nitro
13X6 MA
11,300

I have a new one made in China and have not tached it, but I think it is a bit stronger.

RE: Super Tigre G90
 

What prop would you use for 3D?

RE: Super Tigre G90
 

I would go for a 14x4W ... maybe a 15x4W even.

RE: Super Tigre G90
 

Man, my ST G90 realy came alive after changing the stock mufler for a non mufled tuned pipe, it gained 1000 rpms!!!

Now it has a OS 7D carburator, and gained 500 rpms.

Finally it´s turning APC 15x6 at 11000, great sound, super performance, it´s on a u-can-do 3d .60.

I think it´s a great engine, but i was happy only after changing the carburator, the super tigre carburator sucks, it´s a peace of junk.

Jose Ribeiro.

RE: Super Tigre G90
 

Wow,
I'm swining 14x7 prop and 11675 RPM
using slimline sport scale muffler..

Man this thing is LOOOOUUUDDD:)

here is the muffler I'm using:
http://www2.towerhobbies.com/cgi-bin...&I=LXFG90&P=ML

I cut off about 3.5 inches of the metal tubes, so now the muffler tubes are about 1.5 inches long.


THe stock muffler seems to choke this engine, it needs something area to breath.


Also I'm in BR LA so its hot and humid, pluss the engine isn't even fully broke in. Soon when the weather cools down I'll know I'll be over 12k with this.

RE: Super Tigre G90
 

What plug are y'all running?

RE: Super Tigre G90
 

towerhobbies glow plug.

Its a knock off of the OS but its cheap and works well

RE: Super Tigre G90
 

Love this motor when it runs right. I have a Slim Line Pitts that I think is not allowing my motor to run properly. I have it in a Hangar 9 P-51 (60 size), inverted, swinging a 13X6. The engine is very slow to respond to throttle changes in flight. In fact, when brought to idle, it stays at a high RPM for at least another 5-8 seconds, then eventually comes down, but not anywhere close to a normal idle. It is not exibiting normal characteristics at all. Any suggestions?
Anyone got a stock muffler I can buy off you? I want to see if the stock would stop the surging. Thanks

RE: Super Tigre G90
 

Sometimes an engine will pause before returning to idle when the low speed needle is too lean. Five seconds would be an extreme case.

Here is what I would do:
1. Set the top end with a tack.
2. Back off 300 RPM.
3. After each flight richen the low speed needle 1/16 turn, just a touch.

You want to see if the condition gets better or worse. Careful a large change can skip over the sweet spot. Also the engine needs to be run and cleared out between changes.

Based on the description you may find the low speed just a touch lean. You may also find it OK for the ST 90 to pause slightly before returing to idle. But 5 seconds is too much.

Bill