Super Tigre Carb Tuning
Ted
have had STs before so I know you have a delicate balance between the
low end and high end before you get it just right. I recall reading
somewhere that the position of the spray bar is very critical as well.
Has anyone also heard of this? And what position would be ideal? Most
engines like it pointed straight down but I seem to think the STs
prefer a little upward thrust of the spray so if you are looking from
the needle valve side it would be pointed around 4 o'clock. Any
thoughts or experience on this? Many thanks.
Ted
Martin X. Moleski, SJ
<b975c373-fd62-4388...@w34g2000prm.googlegroups.com>:
I have no personal experience of tuning an ST.
Their web site (and many other people who have
posted here since 1995) recommends that the
hole in the spraybar be straight down:
http://www.supertigre.com/faq/product-faq.html
As often happens with tuning, people disagree
about what works and what doesn't work. In
my view, you should feel free to experiment
and report your results here so that the peanut
gallery can learn from your mistakes. :o)
Marty
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Mark Eastman
Start with the spray bar straight. It may take a tiny twist later but
that is usually your last resort.
The most important thing you can do, in particular with the ST51, is
switch to an OS-8 glow plug. The ST plugs are basically junk.
I fought with my ST51 for months before I came to that simple
solution. It simply wouldn't mid-range well.
Now it runs great, hardly ever needs adjustment, and starts easily.
Good luck,
--Mark
MJKolodziej
"Ted" <tkenn...@msn.com> wrote in message
news:b975c373-fd62-4388...@w34g2000prm.googlegroups.com...
A couple of weekends ago we took apart a ST45 carb. Seems to me(<-that was
a disclosure about accuracy), the spray bar was at 4 or 5 o;clock when
viewing it from the needle end. It looked to be pointing right down the
throat of the engine. I have one I could go take apart and look at if ya
want? Use an OS #8
mk
weedhopper
"Ted" <tkenn...@msn.com> wrote in message
news:b975c373-fd62-4388...@w34g2000prm.googlegroups.com...
The spray bar position is considered to be a tuning adjustment also. In my
club we would swap the ST carb for an OS. Then they would run like a raped
ape.
Morgans
"Ted" <tkenn...@msn.com> wrote in message
news:b975c373-fd62-4388...@w34g2000prm.googlegroups.com...
Is it a true 2 needle carb, and not a high speed needle and air bleed
valve?
If the spray bar changes do not do the trick, and it is a two needle carb,
you might be able to take a trick from the older Fox engines.
The instructions told the user to modify the profile of the low speed needle
to adjust the midrange.
The told you (and they were right) to chuck it into a drill, and turn it
fast, and put some sandpaper to it, either on the tip to "dull it" or the
"shoulder" where the angle met the full diameter of the shaft.
I think (it has been a while) if the midrange was lean, you sand a small
radius on the shoulder. It does not take much, and if you go too far, be
prepared to buy a new needle and try again. DAMHIKT!
<g>
--
Jim in NC
Ed Cregger
"Martin X. Moleski, SJ" <mol...@canisius.edu> wrote in message
news:pdadnUl9hfxn8fTV...@supernews.com...
-------------
Many folks, because of previous exposure to OS "no break-in" engines,
attempt to fine tune and fly a Super Tigre engine long before it is ready to
be put into service. These are the folks that end up complaining about those
miserable ST carburetors.
Marketing will not mention just how long an ST engine needs to be broken-in
because of a possible loss of sales, so they let their customers bumble
around making confetti of their models because of an improper break-in
regime. All marketing cares about is profit. Not their customers' well being
or enjoyment of their purchase.
Super Tigre engines are fine engines, but none of them come ready to fly
right out of the box, like OS. Trying to break-in an ST engine in the air,
unless it is ABC, is pretty much a waste of time and nearly a sure bet to
destroy your model, unless you are very experienced and are accustomed to
deadsticks and their requisite landings.
This does not make ST engines a bad buy. It simply means that one has to
learn something new and employ a test stand for break-in. Once accomplished,
an ST engine will last many decades of fairly rigorous use. Not done
properly, the engine can be ruined in no time flat.
Once the engine is broken-in, the carb that comes with ST engines suddenly
changes into a pussycat to adjust and operate. Surprise!
Ed Cregger
Bob Cowell
>-------------
>
>Many folks, because of previous exposure to OS "no break-in" engines,
>attempt to fine tune and fly a Super Tigre engine long before it is ready to
>be put into service. These are the folks that end up complaining about those
>miserable ST carburetors.
>
>Marketing will not mention just how long an ST engine needs to be broken-in
>because of a possible loss of sales, so they let their customers bumble
>around making confetti of their models because of an improper break-in
>regime. All marketing cares about is profit. Not their customers' well being
>or enjoyment of their purchase.
>
>Super Tigre engines are fine engines, but none of them come ready to fly
>right out of the box, like OS. Trying to break-in an ST engine in the air,
>unless it is ABC, is pretty much a waste of time and nearly a sure bet to
>destroy your model, unless you are very experienced and are accustomed to
>deadsticks and their requisite landings.
>
>This does not make ST engines a bad buy. It simply means that one has to
>learn something new and employ a test stand for break-in. Once accomplished,
>an ST engine will last many decades of fairly rigorous use. Not done
>properly, the engine can be ruined in no time flat.
>
>Once the engine is broken-in, the carb that comes with ST engines suddenly
>changes into a pussycat to adjust and operate. Surprise!
>
>Ed Cregger
Ed:
In your estimation,
Does this apply equally to the new oriental ST engines as to the older ones
Italian manufacture?
bob
MJKolodziej
"Bob Cowell" <bo...@kdsi.net> wrote in message
news:3i7n6456b9efo38dr...@4ax.com...
I'm not Ed but I concur with what he said and I have a newer ST45 and it
took some breaking in and now is much better.
mk
Ed Cregger
------------
Bob, I suspect that the Chinese are making the engines a little better, or
they have switched to softer metals, because I have heard that the newer
Chinese engines take a little less time to come in on the average. I have no
scientific proof of this at all. But lots of folks are reporting, via the
web, that the engines, while not as readily broken-in as OS, are better in
this respect than they were back in "the old days".
I'm not knocking Italy's Super Tigre's efforts either. CNC machinery hasn't
been around all that long, so the Italians may not have been set up as well
in this regard as the current Chinese manufacturers.
These are simply my impressions and nothing more.
Ed Cregger
MJKolodziej
"Ed Cregger" <ecre...@bellsouff.net> wrote in message
news:g4gksh$sml$1...@aioe.org...
This last ST45 I bought woud NOT turn over by hand when I got it. I added
oil and rotated it without a glow plug until it got better. It's one of the
higher RPM ST45s at the club now.(we race 'em)
mk
Lyman Slack
Here in Florida we've been running the ST .40s in a Club 40 Pylon Race
program, having switched over from the OS .40LA. Most of the racers are
running the STs in for a few tankfulls before flying. Other than a few
deadsticks, these new engines seem to be OK with an in-fight break-in. Most
fly with a smaller prop than what they will race with, and certainly do not
run the lean at any time. After a while, no one is having and problems. We
supply 15% Cool Power fuel and most of the guys are happy with an OS #8
plug.
Cheers -- \_________Lyman Slack________/
\_______Flying Gators R/C___/
\_____AMA 6430 LM____ /
\___Gainesville FL_____/
Visit my Web Site at www.LymanSlack.com
"Ed Cregger" <ecre...@bellsouff.net> wrote in message
news:g4gksh$sml$1...@aioe.org...
>>>Super Tigre engines are fine engines, but none of them come ready to fly
3for3
My experience with the 5 ST engines that I have owned/own has been varied.
I have never experienced that moving the spray bar has made a difference in
the performance of the Super Tigre engines. I have also tried placing a
brass ferral in the carb throat to decrease the intake diameter with no
positive effect.
Today I have two G-51 that are three years old and they both misbehave on a
regular basis. One is on a Seamaster and I have the low needle at 8 plus
turns out to keep the low end and mid transition from going lean. The other
G-51 is on a trainer and is always full of surprises. I don't know if these
engines are sensitive to barometric pressure or the alignment of the
planets. Some days they run very acceptable and other days they are
threatening to stall during transitions.
I have a G-45 and a 40 (Italian made) that run like clocks with no issues
what so ever.
I did own ( and now returned to Tower Hobbies with full refund) a 61 size
engine that ate three planes.
I see others peoples responses indicate that they need a lot of break-in. If
more that three gallons of fuel does not qualify for break-in, then I need
to sell these G51's to some unsuspecting person on Ebay and go buy some
magnum XLS-46's.
I have not replaced my temperamental ST G-51's because I am frugal and I
like a dead stick challenge at least twice a week. If I were to purchase new
engines I would not purchase a ST again. I own OS, GMS, Magnum, Jett and
Weston engines and do not have the trouble that I have with the two G-51's.
On a side thought, maybe the issue with the G-51's are a quality issue with
machined surface tolerances and are on the margin of acceptable dimensions.
Does anybody know what happens when the crank intake area under the carb
opening and the inside wall of the crank case get leaky?
Thanks for reading
RCS
"Ted" <tkenn...@msn.com> wrote in message
news:b975c373-fd62-4388...@w34g2000prm.googlegroups.com...
Ed Cregger
"Lyman Slack" <lys...@bellsouth.net> wrote in message
news:0iSak.21377$AJ6....@bignews8.bellsouth.net...
> ED --
>
> Here in Florida we've been running the ST .40s in a Club 40 Pylon Race
> program, having switched over from the OS .40LA. Most of the racers are
> running the STs in for a few tankfulls before flying. Other than a few
> deadsticks, these new engines seem to be OK with an in-fight break-in.
> Most fly with a smaller prop than what they will race with, and certainly
> do not run the lean at any time. After a while, no one is having and
> problems. We supply 15% Cool Power fuel and most of the guys are happy
> with an OS #8 plug.
>
------------------
Running a smaller prop would let the engine run cooler when wide open. That
might be helping the situation a bit.
The GS-40 engines that I have seen rev up really well. Frankly, I didn't
expect anything nearly as dramatic in power production. They are still one
of the best buys in R/C.
Ed Cregger
Ed Cregger
"3for3" <mor...@nospamyahoo.com> wrote in message
news:aB2bk.3284$vn7....@flpi147.ffdc.sbc.com...
------------
I'm going to treat this subject as though there are folks reading my
response is brand new to the hobby - not you.
The first thing I would do is to compare the ST.51 engines' features to
those of the engines you own that run well. Are they ringed? The ST.51 is a
ringed engine. Are you using the same glow plugs in all of your good running
engines and is this the same type of glow plug that you are using in your
G.51 engines? Fuel? Prop sizes for equal and near displacements? Inverted
engine installation?
Can you see where I'm going with this? I realize that you have probably
already been through this routine, so forgive me for being simplistic, but
many times the things that are causing us grief are simplistic.
If your other ST engines are running great and are nearly the same size,
might not their carbs switch with your problematic .51 engines? Might be
worth a try.
A ringed engine can have quirks in running that are caused by a defective
ring, or a defective ring slot in the piston. Changing a ring and inspecting
the ring slot/groove is an easy process and is one that might yield an
answer to your problem. I can think of nothing about the ST.51 design that
is problematic on a regular basis.
I am not telling you that I don't believe you or that you are hallucinating.
I believe you. Let's get to the bottom of this. Now it is time for you to
answer some of the above questions, if you please.
Ed Cregger
Jim
Here is what I learned the hard way:
DON'T MESS WITH THE SPRAYBAR POSITION FRO THE FACTORY!
The secret to getting an ST to run right is as follows:
1.Start and adjust for high end mixture. Stop engine.
2. Connect a piece of fuel line to the carb that is long enough you can put
the other end in your mouth to blow through.
3. CLOSE the idle mixture needle.
4. While blowing into the fuel line, open the idle needle until you can JUST
hear air coming through.
5. reconnect fuel line and start engine. Adjust high end needle again.
You are done.
This will normally set up the carb nearly perfectly and allow transition
from low to high throttle without the 'stumble'.
Good luck!
"Mark Eastman" <rcfly...@gmail.com> wrote in message
news:8fe1bf5d-4d39-43ca...@f36g2000hsa.googlegroups.com...
Jim
"Ed Cregger" <ecre...@bellsouff.net> wrote in message
news:g4gksh$sml$1...@aioe.org...
>
Jim
the typical 15% coolpower, etc. fuel. But then I have been running bigger
Tiger engines too!
"Lyman Slack" <lys...@bellsouth.net> wrote in message
news:0iSak.21377$AJ6....@bignews8.bellsouth.net...
Ed Cregger
"Jim" <j...@slaughter.org> wrote in message
news:wIbbk.283$713.182@trnddc03...
>I have the best luck with "Tiger Fuel" which is lower in nitro and oil than
>the typical 15% coolpower, etc. fuel. But then I have been running bigger
>Tiger engines too!
Just don't mistakenly burn it in the smaller engines and tune them the way
that most folks do. Smoke city.
Ed Cregger
3for3
Hopeflully this information will satisfy your curiosity. I have replaced the
stock carb with a perry carb with no improvements. I did replace the ring in
one of the two engines with no improvement. I buy plugs a dozen at a time
and all of my 2 cycles have the same plug. All of my 2 cycles that I own use
the same 15%N 20% synth/castor mix fuel.
I have an 10.5 x 6 on one engine and a 9.5 X6 on the second. These engines
were purchased within 6 mos. of each other 3 to 3.5 years ago.
I'm done with the one. If you would like, I'll ship it to you. If you fix
it, let everyone know what I did not do to get the engine to run
satisfactorly.
thanks,
rcs
Ed Cregger
-------------
There have been a lot of posts through my mind since your original post, so
pardon me if I get confused with the particulars of your situation.
All of the props you listed are small for an ST .51, so I assume that you
are trying to go really fast with this engine. Frankly, picking a large
displacement version of an engine that was built in a smaller engine's
crankcase was not the best move. Notice how heavy the Rossi .45 engines are?
That's because they carry more metal in their cases, metal that can be
removed to form larger bypass passages. The larger bypass passage permits
the Rossi to breathe better and produce more power. Usually at a very high
rpm. If you read some reviews, you'll notice that folks are not generally as
happy with the .53 sized Rossi either and for the same reason as the .51
Tigre. The larger displacement engines should be used to carry more prop and
conventional rpm levels and not used for very high rpm engines.
My choice, had I wanted a Super Tigre to go fast in that size range, would
have been for the .45 ABC. It would have been a better engine for high rpm
operation than the .51.
Sorry if I'm completely disconnected from this thread. Thunderstorms in the
area mess with this old man's noggin.
Thanks for the offer of sending it to me. That was nice of you, but I'm very
busy with my recording studio (amateur), motorcycle and ham radio. Flying is
being relegated to very small glow and electric models these days. Good luck
on your next choice of engine.
Ed Cregger
bgferr1
Can you provide me some basic instructions on tuning my smaller (less
than 120 sized) SuperTigre carburetor?
To properly set up your carburetor, there are a few steps...
Make sure the spraybar is set so that the fuel slot is pointed straight
down the center of the carburetor. You will have to look through the
carb from the bottom, with the venturi opened to full. Loosen the two
screws next to the high-speed needle valve to rotate the spraybar so
that the slot is centered.
The idle needle can be seen in the slot of the spraybar. It looks like
a piece of wire that has the end squarely cutoff. It should be less than
one-half way across the slot when the venturi is opened to full.
The high-speed needle should be opened about 2-1/2 to 3 turns out from
closed.
All of these settings are very rich. You'll have to start the engine at
about 1/4 to 1/3 throttle. Once the engine starts, advance the throttle
to full. You can then lean the high-speed needle until the engine is
running just rich of peak RPM.
Once you have the high-speed needle set, you can retard the throttle a
bit and use the idle needle to adjust the engine. Retard a bit, and
adjust. Keep doing this until you have reached the desired idle RPM and
mixture. Remember, since we started out with an intentionally-rich
setting, the idle mixture will have to be leaned.
Finally, the midrange can be adjusted by rotating the spraybar a hair.
Just loosen the two screws next to the high-speed needle and rotate the
spraybar just a tiny bit. Either direction is OK. This will help you get
a good transition and midrange.
--
bgferr1
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Ed Cregger
a recent OS and did not need midrange adjustment of the spraybar unless you
were running a tuned pipe. Sometimes not even then.
Ed Cregger
"bgferr1" <bgferr1...@rcgroups.com> wrote in message
news:bgferr1...@rcgroups.com...
bgferr1
It's a new GS 40 made in China not Italy. The info on my previous post
is straight from the FAQ section of the Super Tigre website. I have yet
to try it, but I will soon as I am having issues on the transition from
idle to wot.
Robert Scott
> How old is your Super Tigre engine? The older series of ST carbs tuned
> like a recent OS and did not need midrange adjustment of the spraybar
> unless you were running a tuned pipe. Sometimes not even then.
>
> Ed Cregger
I have around two dozen Super Tigre engines and I don't think I've ever made
the famous spraybar "midrange adjustment."
I think Super Tigre's hard-to-tune reputation is undeserved and intimidates
some folks.
Good flying,
desmobob
Ed Cregger
"Robert Scott" <desm...@earthlink.net> wrote in message
news:bd-dnZedIbY8Oz3U...@earthlink.com...
--------------
Agreed.
The problem, as I see it, is that folks plop a NIB engine on a model and
expect it to be able to tune it right up and just fly. That's not how many
glow engines work right out of the box. There is that necessary thing called
break-in.
Many brand new engines are not reliable in idle and transition until they
have had at least four or five full tanks of fuel rank through them and even
then they will improve significantly over the next twenty or so tanks of
fuel and will require retuning now and then.
Then to further exacerbate the "problem", folks fit the engine with a 12"
low pitched propeller, which compounds the problem and makes an engine that
is designed to run on 10" props struggle with swinging a huge windmill.
Super Tigres were designed to rev up. The standard prop for a .40 to .45
back when these engines were designed was a 10x6 or 7, NOT an 11x6 or a
12x4 - 5.
Wanna make it even worse? Use fuel with 15% or more nitromethane. Suddenly
we have a midrange that is too rich, so what do we do? We use an OS Type F
glow plug which ratchets up the problem even more.
OS Engines has followed these usage trends by designing engines with extra
large cooling fins and more of them. The result is that these engines will
tolerate larger propellers and greater amounts of nitro without a problem.
To even make it better yet, their machining specs are so much tighter that
their engines really do not need an old fashioned break-in. Just the token
break-in described in the instructions.
Gee, now I feel better that I have a couple of OS .55AX engines. Maybe,
after completing a few sales and swaps to help clean out the garage, I'll be
able to resurrect my Fun One and plop one of the .55AXs on the Edson
Universal Adjustable Engine Mount that I bought from MECOA/RJL a short while
ago.
Ed Cregger
Ed Cregger
Run four or five tanks of fuel through it on the ground, but elevated three
feet, very rich to seat the ring. Keep running the 10x6 or even a 9x6 or 7
sized prop. Don't fall for the 11x6 thing that folks will tell you to use.
The Super Tigre .40 was designed in an era of high revving engines - noise
be damned. If you try to lug them down with a large prop, you will
experienced a rich midrange, even after break-in is complete.
The GS-40 is a great engine. Congratulations. There is nothing wrong with
the carb.
Ed Cregger
-------------
"bgferr1" <bgferr1...@rcgroups.com> wrote in message
news:bgferr1...@rcgroups.com...
>
Waterbug
There is a premium plug from Enya that solved the midrange barbling when
accelerating from idle to takeoff. After dinking (n optional) around
with two ST51's from the 90's I found the extra buck or two for the
premium plug to be the permanent fix. Went from deadstick dog to
reliable.
Frank Bowman, a piston ring fitting guy who I no longer seem to be able
to contact, clearly stated to me in an email that he religiously laps
the liner tops on Super tiger liners that he is fitting rings to. He
said that they are notorious for not being flat enough to seal properly
at first. Perhaps the "extended break in" is the period of time to gum
up the leaky head? I've seen more than one exhibit "mystery" drops of
fuel and oil coming off near the head gasket level.
But the Enya #3 has higher platinum content- most of our "platinum"
filaments in glow plugs are a sponge impregnated with a little platinum.
The platinum is the magic which catalyzes the glow fuel to "compression
ignite". One theory for why the enya 3 works so well is that it has
more platinum for much longer. Sure they're $6 instead of $4, but mine
all last for years.
--
Waterbug
------------------------------------------------------------------------
Waterbug's Profile: http://www.rcgroups.com/forums/member.php?u=34340
Larry Stahl
Might you also repair these engines? I have one SuperTigre 40, made in Italy,
in original box - I think it was crashed. There is a label that reads: "S 40
ABC W/M" and below is written: "cod. 11001824". I know nothing about
this engine, except it appears to be very well made. So, anything you can tell
me is appreciated. Thank you.
--
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