I have several Super Tigres and the fellow who used to set them up for me has passed away. He could make a ST really scream. The question I have concerns a ST 75(Italian made). Can anyone tell me with a reasonable certainty, what direction the spray bar should be pointed in?. If looking from the needle valve side of the carb the bar is at the 4 o'clock position. Logic tells that it should be at 6 o'clock but what do I know. Any ST pro's out there?
On Tue, 13 Nov 2007 14:29:43 -0800, Ted wrote in :
My recollection of advice from Clarence Lee's column matches your theory: 6 o'clock (hole pointing straight down the throat of the carb).
While waiting for ST experts to chime in, you could try that position and see how it works for you.
"One observation is worth 10,000 expert opinions."
Marty
Marty is correct.. 6 o'clock is the correct orentation.
But..
It may have been rotated to the 4 o'clock position to correct a "too rich" mid range..
(The "non instruction sheet/textbook " method of adjusting the midrange mixture in a ST carb...)
Dave
:
Interesting. mk
refer to "Super Tigre set up - by Pe Reivers"
Ditto that! Check Pe's instructions.
The way to set the low end on a ST carb is to connect a piece of fuel tubing. Close the idle needle all the way down (don't force it!) Then blow in the tubing as you open the needle. JUST when you can hear a little air 'hissing' out of the carb, it is set! Leave it alone. Now all you have to do is concentrate on the high end like any other engine. It is the low end that gives people fits with ST carbs. Not set right and it won't transition or idle with a dang.
I also had a problem with the ST carbs and my dear friend Austin (may he RIP) told me the secret years ago and it has not failed me since.
Previously, the engine would cut out, usually right after takeoff. Bad scene.
He said the spray bar has to be positioned so the spray hits the rear of the carb wall- not straight down or at an angle.
This has worked for me very well on my ST .90 on this plane:
Nice plane! mk
Thanks. The ST cylinder head is at the 4'o'clock position so the exhaust exits straight down. It gets hidden in between the plastic dummy cylinder heads.
No exhaust oil gets on the plane.
Ted --
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