I just requested the Chief email specials

Here's the price of the Siato's you are interested in:

SAIE .72......................... 210.00
SAIE .82......................... 239.00

SAIE .72GK....................... 235.00
SAIE .82GK....................... 265.00*

*Includes FedEx Ground Freight

I would go with the .82GK. They look sweet though with the UCD cowl you can't see it you never know what you want to drop it in next!

For the $$ difference I would go .82. It's a 1/2 Oz lighter than the .72 + more umph!

Rif,
Didn't know about the email specials. How much do you pay for 100? 279.99?
thanks,
Barry

I bought my 1.00 GK about a year and a half ago and don't remember what I paid for it. It is still in the box but is going into a Funtana 90 that I am putting together at the moment.

Chief has them email special right now for:

SAIE 1.00......................... 265.00*
SAIE 1.00GK....................... 279.00*

*Includes FedEx Ground Freight

I am not promoting chief over anyone else. They treated me well and at the time I purchased they had about the best deal. There may be better deals out there but I don't know as I haven't been in the market for a Saito lately. I do like the Saito's. I have four 4 strokes, two Saito's, one YS and one Thunder Tiger. They have all been great. The Thunder Tiger is a bit on the heavy side though.

Riff

Any other deals that people know of going on with the saito 82 would be great...

Thanks..

(going to order tonight probably)

If everyone is putting Sato .82's on their ucd's and adding weight to the nose to get the ballance somewhat right, why dont you put a O.S. 70 on it and not add any weight and increase the horsepower???

I say this from experience

The UCD46 has a CG range from about 4.5" to 6.0". Mine balanced easily, with only movement of the battery, at 5 5/8" with the Saito 82. It flies nicely there. One of the easiest landing planes I have. I didn't need to add any weight to balance. Mine weighs 5 lbs 14 oz ready to fly less fuel.
Thanks,
Barry

Does everyone setup their throttle linkage as per the instructions with the linkage made into like a U and looped forward to back or is there a better way?

Are you guys big four stroke lovers? If so then I understand why you are going with these engines over two strokes. I've added no weight and have unbelievable power with my OS 50 Heli Hype.

Four Strokes are great!

They sound cool (more scale sounding)
They can swing bigger props especially at lower RPMs which is very desireable for 3D.
Very high torque motors.
More efficient fuel wise and cleaner running.

The most important thing is the superior torque, especially at lower RPM. Two strokes need to be wound up to generate their power.

Riff

I thought I would ask....

I'm happy with my two stroke and challange any four stroke to perform on the UCD as well as the HYPE.

But I do understand you all side. Enjoy..........

In my experience, insane power saves your plane from crashes. Maybe that's because I'm not that good yet, but being able to rocket out of a descending over if I get in trouble is very comforting to me. "Hovering at half throttle" is not the whole story. Everyone's plane "hovers at half throttle" it seems, but the vertical pull-out is vastly different from engine to engine. I think that the weight increase with a larger 4-stroke is negligible on a plane like this. I don't have a UCD, but I have 2 other .40 sized 3D planes with similar weights and wing areas.

If you want the power and the extra weight bothers you, try switching to a lipo setup (you get 6 volts that way too instead of 4.8), and voila, there's your extra weight back off, plus you've now got more torque on your servos. Hehe, this all assumes of course that money is not a factor. A Saito 100 costs a great deal more than a typical .46 2-stroke. Not to mention the cost of lipos and lipo chargers.

Hello Guys

the OS Heli Hype, is insane power on this size platform, as a matter of fact, in a climb out it will make a Saito 100 look like it is in revers pitch. and its cheaper, something like $ 209.00.

Bob Sawyer

True, a comfortable pull-out is necessary and should dictate the powerplant. Hovering at half-throttle is more a stick position than a true power output. I can't remember who recommended it first, but it is good advice to play with your throttle curve until you have a central stick position for hovering and torque rolling.

I have a Saito .91 in my .40-sized UCD. It is a good match for the airframe.

JC

A reason 4 strokes are better for 3-D

Basically fellas 3D flying (pulling out of hovering) comes down to static thrust. This is the thrust that your engine produces when the plane is not moving. Oddly enough the pitch of the propeller only comes into play indirectly. The major factor is prop diameter and RPM.

The prop diameter is so important because static thrust increases cubically (not squared) to the diameter of the prop that means that if you swing a 15 inch prop with a four stroke and compare it to swinging a 13 inch prop with a 2 stroke, at the same RPM, you are gaining 50% more static thrust. Now you can make up for the difference with the 2 stroke if you spin the prop 50% faster than the two stroke. But that means that you need to spin the 13 inch prop at about 15,000 rpm. The problem with the two stroke is that because it produces less torque it will take it longer to reach 15,000 rpm. Than it would for the 4-stroke to reach 10,000 with their respective props. This means that even if you could get 15,000 rpm from the two stroke, unlikely, the throttle response ( which is very important during hover) would be slower than the 4-stroke. This is why 3-D fliers have gravitated toward 4-strokes.

The way pitch comes into the equation is that when you increase the pitch of the prop (increasing top speed), or the diameter (increasing static thrust) you increase the horsepower you need to swing the prop. This is why 3-D fliers use lower pitch props. Usually in the neighborhood of about 4. This allows them to swing a larger prop (thereby increasing the static thrust), while sacrificing top speed (which is not that important to a 3-D flier anyway).

All of this logic applies in reverse for High speed aircraft.

I hope this has answered some of your questions as to why 4-Stroke engines are more suited to 3-D flying.

Oh and one more thing. I would put my UCD with a lowly 70 surpass against your 2-stroke any day. And I would win. Not just because I have physics on my side but because mine is better.

Nmking09

nmking09

Thanks for the entertaining writing however; it is an opinion and not fact. I find it insulting that you would call me and anyone else a liar, stating that we were incorrect in our post of 15000 rpm. Maybe in your corner of the world two stroke engines cannot reach such speeds, but on this side of the Mississippi, they reach those speeds and do it quite often. You also stated, “This is why 3-D fliers have gravitated toward 4-strokes” yet again another opinion.

Yes, you are right, yours is better, that is why O.S. keeps producing two stroke engines and making a profit, because your “lowly” four stroke is better.

I care not to challenge you my friend, but any time you would like to fly with us, you are certainly welcome even with your “lowly” four stroke.


The beauty of this country and this sport is that we have choices. Everything has its pros and cons sir, everything!

Actually most of my post is supported by fact. Propulsion, Aerodynamics, and Physics are facts, Unless you believe that your plane is supported in the air by some sort of mystical magic, you must concede that propulsion is determined solely by physics, This is what I tried to present in an impartial manner.

The main problem as I stated in my post is not getting to high rpms with a 2 stroke, It is getting to them quickly. It is like comparing a 0-60 speed of one car with the 0-100 speed of another. If you have any specifics concerning my physics or the math I used to derive my conclusions I would be happy to hear any factual information you have. This does not mean saying that my post was an opinion, Give me some reference information. I would love to learn more about aviation and propulsion, that is why I am currently studying Aerospace Engineering and Physics.

The comment my ucd is better than yours was a failed attempt at a joke. Sorry if it offended. But seriously I would like to see what it can do.

Nmking09