This is a bargain on the carb. it was like $75 last year

They are dumping it

If you look at how the metering actually works on the new Chinese made Super Tiger carbs on the inside and how the new GMS 76/Tower75 carbs work on the inside, The low speed metering needle and the slot are identical.

These carbs have excellent mid range out of the box.

The old Italian Super Tiger carbs had a "Cat Eye" shaped metering outlet on the spray bar and the narrow edges would plug with filter fuzz.

The new Chinese ST carb have a square sparay bar outlet just like the GMS

The old style GMS/Tower carbs had the fuel coming out the end of the spray bar and there was a gap between the spray bar and the LSN when wide open

I just make sure the fuel nipple on the carb is pointed at the rear engine mount hole, fixes any problems with tuning right up.

I completely agree with all the positive comments about the old ST carbs. I alsways thought they were the best carb made

The reason I used Magnum carbs on my ST G90 was because my G90's came with ST 40 carbs

The difference between the old ST 40 carb and a G61 carb was the flat sidded spray bar on the G61

I eventually changed the spray bars in my original G90 carbs before I sold the G90's

I sold the Magnum carbs separately

I use 10-15% nitro in all my engines including Super Tigres. All engines are dumb. They don't know what you are running through them.

100% agree!!!!! I did so and received and excelent tunning in all ranges.
Also REPLACE THE ORIGINAL MUFFLER!!!!; will spin a 15 in propeller without any problem. Look a post of henning; he did it.

Cheers

I have the ST 51, 61, 75, 4500. and they all run great. just be sure the spray bar is facing in the right direction like CowboyLifesaver said. Never had a problem with any of mine. I always run omega 15% fuel and os#8 plugs.

That's like running premium gasoline in a car made for 87 octane gasoline. It's a waste of money at the very least.

On really hot/humid days, the typical European glow engine will protest burning more than 5% nitro. If you listen carefully, you will hear a sizzling, frying eggs sound coming from your engine when airborne. That's a sign that the engine is running with the ignition timing too far advanced. Either back off the nitro, run a smaller prop load, change to a cooler glow plug or reduce the compression in order to eliminate the frying egg sound. When engines are running with the timing too far advanced, they tend to overheat and they become unreliable on throttle-up or idling.


Ed Cregger

Ed- at what temperatures/humidity are you saying this will happen? I live way up here in Ohio and this doesn't happen in my G90s or 2300 running 10% but it doesn't get over 90F much here.

Ed

i have a ST 2300 and runs real good on omega 15 % so does my ST .61. glow drive the 2300 at idol or 100% if you can,really makes a difference. don't run either to lean. 12x6 prop on the .61 and an 18x8 apc on the 2300 works great. these are both china engines. there is no cheaper power that i can think of. they now have some electric stuff out too. check tower hobbies, for motors and esp's............RON

I've been running a new style ST2300 on 10% omega for a year or so now on a HEAVY Sig Fourstar 120. Try an APC 17x10N if you can find one. This provides awesome power and spools nicely from idle to full power 1900rpm up to 7800rpm. I use the stock carb and muffler. The midrange is not an issue. The ripping sound when diving at full throttle into a split s gives me goosebumps. I'd fancy a guess that I've got one of the quicker four-stars out there given a bit of altitude to use in a dive.....







PS These things can't be that hard to tune. This is only my second glow engine and no "field experts" have ever touched the thing......

Anyone that wants to get rid of there ST carbs that has not been trashed and are complete give me a PM, I will gladly take them off your hands .
Like someone said in here earlier, I to have used the ST carb many times to replace a not so quality carb of a different make and had nothing but great a running engine afterwards.

Heres a link to a pereivers fact sheet written some time ago it follows the instructs shown earlier with one difference, read carfully about what he says about the rotation of the spray bar, I have found this to be a fact. The older tigres had this in there instructions NIB but for some reason dropped it on the newer ones.
http://home.wanadoo.nl/pereivers/sup...tructions.html

That document says that rotating the spraybar will richen the mixture, but isn't it true that most peoples issues are with mid range being too rich? At least thats what I've observed...

The document says turning it one way richens it and the otherway leans it.

" In cases where poor transition occurs when opening throttle, a variation in the mixture strength can be obtained by rotating the fuel inlet spray bar so that the fuel pipe nipple is pointing at the front engine fixing hole in the mounting lugs. This rotation brings the slit in the spray bar towards the front and will richen the transition mixture and vice versa. This rotation is only documented in this series instructions, and is omitted in later versions. It seems that clockwise rotation slightly richens the transition and anti-clockwise rotations leans the transition."

I have never done this because the many ST engines I have run have never needed this once you have a decent muffler back pressure. Good muffler back pressure allows you to set the carb so you get even throttle response from idle to full throttle (NO rich midrange).

Ed

I've heard that rotating the spraybar will richen or lean the midrange on Super Tigre carbs but I'm at a loss the see how or why. It seems as though the same amount of fuel would still be moving through the system given the muffler pressure. As others said previously I haven't had any need to mess with it.

According the the current Super Tigre info (stickied at the top of the SuperTigre product forum) the spraybar should be pointed straight down.

It has to do with the rotating hole in the barrel and how the airflow comes across the opening slit or slot in the spray bar

Thanks for the tip, $24 for an OS carb is a bargain. I know the 4B and 4BK carbs have a smaller diameter outside mount diameter (FSR days) than the newer SF/FX/AX carbs. I'm unfamiliar with this heli configuration. I guess it's micrometer time and pulling
a carb out to see if it's .39 (10mm) too. This is cheaper than a Perry carb. Worth a try, but not on my Tigres, they tune just fine.
I need a replacement for my ASP engine.

ASP and Magnum are the same engine. get a Magnum carb

I run OS F plugs in everything

I never had a problem tunning this engine but i was looking for just a little more power. It is on a sig 1/4 clipped wing cub and i need all of the power i could get out of it, and i was flying off of a short runway with big hill on one side and 50 food trees on the other. A few times i was at w.o.t. and still not sure if i would clear the trees.

Thanks for the advice. Are you saying the Magnum carbs are better? I've got a couple of old Royal carbs that fit also, but figured it was adding insult to injury. (P.S. When I was poking around on tower for the heli carb order, I found that new Revolver 60 ARF video impressive!)

My OS heli carb does not fit a ST G90 and is not bigger on the inside. At the time I had the G90's the OS carbs were priced out of site.

The Magnum 108 carb fits the ST G90 like it was made for it. The replacement carb comes with a spring steel insert to reduce the venturi. Even with this reducer the venturi is still larger than a ST.

I ran my G90's with APC 14 X 6 props and the Magnum Carb with the venturi insert and they turned 11,000 rpm. with the genuine ST G90 carb they would only do 10,500 with the 14 X 6

I also ran 15 X 6 and 15 X 8 props on them. The engine did as well or better with the ST carb. with these big props. The engine did not over heat but spool ups were slow.

With a 13 X 6 the G90's seemed to be running too fast for the torque and power curves. The 13 X 8 was acceptable. All props were APC's

The S90K with the four bolt head or the S90 with the machined dished 6 bolt round head may do better than a G90 on a 13 X 6 because on these engines, the internal port passages are larger

Regarding Super Tigre carb problems. Jett Engineering that manufactures the Jett RC Engines has had so many requests that he now makes carbs and their tuned mufflers for the 3000 Super Tigre Engine as well as the other models of these types. There is a big improvement with these installed. There is an RPM increase, but a far greater torque increase which yields greater thrust. I have personally observed a fellow flying club member's model airplane with a tuned pipe and I was not that impressed, but since he converted over to a Jett Tuned Muffler, it screams now. A big and noticeable improvement over his tuned pipe. It may cost up to $85 for the muffler depending on your make/model engine for the Jett Tuned Muffler, but it is worth every nickle. Jett Engineering Carb replacement will also cost $85 for these engines as shown at his web site. http://www.jettengineering.com/

Hope this helps those wanting more out of their Super Tigre Engines. Since I have read that these engines are long lasting engines, I will be ordering the Jett carb and muffler for my new ST-3000 engine as soon as I find what planes are suitable for using this engine in.

super tigre carb. gurus. when adjusting spray bar for rich or lean, which way leans and which way richen the mid range mixture????

fuji, read post 39