ST 90 replacement

What is the best 2 stroke 90 to replace a ST 90? If the bolt pattern is the
same that would be a plus.
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL)
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Reply to
Dan Thompson
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Webra. Dr.1 Driver "There's a Hun in the sun!"
Reply to
Dr1Driver
Ditto.
Reply to
Paul McIntosh
What is the best 2 stroke 90 to replace a ST 90? If the bolt pattern is the same that would be a plus.
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Reply to
Dan Thompson
I'm curious... why not another Super Tigre? Are the new Chinese STs not up to snuff? (I have about 15 of the Italian ones and like them a lot.)
Good flying, Bob Scott
Reply to
Bob
I swearing off ST for the future. I have been a user since the very early 60's and have numerous engines, I.E. Several .23's, .40, 46, several .56, 60 and two 90's. One of the 90's I just can't get it to run correctly. If mid range is right, them the low or high is not right. Get idle and high correctly, mid range is bad. Hesitates on acceleration. ST is the only engine I have had this kind of problem. I thought of replacing the carb, but why spend $65 for a carb on a $130 engine? If I am going to spend that kind of $$, I'l just get another engine which can't be any worse than what I have now.
I have about 8 ST .56's and if you look at them there are several different designs of carbs. There must be at least four different designs in the 8 units. Two of the carbs look identical except the throttle body works backwards. Low position for one is high position for the other. This tells me ST is still trying to get it right. I'm tired of dead sticks and tinkering on this engine.
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Reply to
Dan Thompson
Dan have you tried putting an Enya #3 glow plug and going with 15% nitro in your ST engines? They say that ST engines is a love/hate relationship and I love em! I would gladly take that faulty 90 off your hands!
Sherman
BTW I have a new Chinese made ST 90 still in a box but other than the made in Italy stamp it looks identical to the other ones I have
Dan Thomps>
Reply to
Sherman F. Dickson II
I've tweaked many a needle on motor's that had that problem (Fox 40's, mainly). Takes just a couple minutes with a Dremel once you get the hang of it. If it's fat in the mid range, you can taper the tip and then thin the base where the flat starts to end to get the other areas richer.
Reply to
John Alt
Get in line! :)
I will take that STUBBORN,CRANKY, GOOD FOR NOTHING DEADSTICKIN ST off your hands!!!
I will even pay the freight!
:)
Dave
Reply to
dgamblin
It's that tinkering I don't want to do. In this day and age the other engine makes don't require me to re-engineer them.
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Reply to
Dan Thompson
I normally OS #8 for my two strokes and yes, 10% and 15% fuel.
However, FWIW.
Speaking of plugs..... As you know Saito comes with the McCoy #9 plugs which I have never been able to use since I do like an engine to idle. I use OS "F" in my four strokes.
When I break in an engine, I assume the first plug will need to be replaced after roughly 10 tanks of fuel. Due to this, I needed to break in some Tower 46 and 75's and to use up these plugs they were selected to be the sacrificial plugs. To my surprise the MC#9 runs fine in the Tower two strokes and I have been using them ever since in the Tower engines. HUMMMMM......maybe I should try one of these in the ST90.
There is always something to learn!
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Reply to
Dan Thompson
If I replace it, it will probably go on eBay and you all can have your chance.
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Reply to
Dan Thompson
Have you tried swapping carbs since one obviously runs well? See if the problem follows the carb. It may point to something else.
t
Reply to
oneballlow
If I replace it, it will probably go on eBay and you all can have your chance.
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Reply to
Dan Thompson
I normally OS #8 for my two strokes and yes, 10% and 15% fuel.
However, FWIW.
Speaking of plugs..... As you know Saito comes with the McCoy #9 plugs which I have never been able to use since I do like an engine to idle. I use OS "F" in my four strokes.
When I break in an engine, I assume the first plug will need to be replaced after roughly 10 tanks of fuel. Due to this, I needed to break in some Tower 46 and 75's and to use up these plugs they were selected to be the sacrificial plugs. To my surprise the MC#9 runs fine in the Tower two strokes and I have been using them ever since in the Tower engines. HUMMMMM......maybe I should try one of these in the ST90.
There is always something to learn!
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Reply to
Dan Thompson
Let us know when it goes up on E-bay
Tom
Reply to
tomb046
Thought of that, but I have a sorta motto that if it is not broke don't fool with it. I would end up with two engines not working.
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Reply to
Dan Thompson
How bout a Super Tigre 90...........Tower has them on sale.... and the bolt pattern is the same...........
Reply to
DAYFLIER
In my experience ST carbs STINK> I replaced the one on my 90 with one from an OS 61 I had laying around and it runs like a champ.
Reply to
scooter
Which OS .61? FSR? SF? SR?
Reply to
Don Hatten

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