RC-CAKES

My Feedback: (4)

Here are some pics of the fit issue... Thanks so much for the assistance. I will just order a new one and have this as a spare for the bigger engines. Do you know if the FA125 carb is the same as the 100? BTW: that long screw standing out at the top is the old plastic back screw I used to temp. keep the velocity stack from sliding off & losing its Oring!

w8ye

My Feedback: (16)

It is not a carb for the Saito 72

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The Saito 72 and 80 use the same carb

The 82 and 91 use the same carb

The saito 100 and 115 use the same carb

The Saito 125 has its own carb

RC-CAKES

My Feedback: (4)

one more wide shot

w8ye

My Feedback: (16)

It is probably for the 100? I doubt it is for the 125

However, the new 91 carbs look this way. The old 91's had the spring

Rudolph Hart

Thanks for that.Whats the longest distance away i could put that.Motor is an fa220 inverted in a seagull arf percival mew gull.

RC-CAKES

My Feedback: (4)

Thanks to all for the assist with this 72. I will post the progress when I get her running once the new carb arrives. With my 3.25 Saitos - do I qualify for CLUB status?!

FNQFLYER

Old fart, I used to hang them below the motor on a short bit of fuel tube and usually attach to a convienent place on the f/wall.

FNQFLYER

A question for those who know (cause I have sort of forgotten).  What sort of horse power could I expect from an early 90's 120 fourstroke.  I am looking at substituting a late model Saito from 82 upwards.  I have all the ususl problems fitting it under the cowl and inside it length wise.
Any ideas people my thought that a 1990 4 stroke (120 size) would put out about 1.4 to 1.6 hp

w8ye

My Feedback: (16)

The biggest difference between the Saito 120 and the newer Saito 120S is the size and weight.

FNQFLYER

What I am looking to do is obtain the horse power of the early 1990's fourstrokes especially the 120s, so I can then compare that with what is available today in smaller engines.
The cowl I have to fit it in is 103mm long and 194 in diameter. (for a Marutaka / Royal Stinson Reliant).  As an example the Saito 91 puts out 1.6hp I think and the Saito 82 puts out 1.5 hp (this would make it a suitable substitute, and most importantly it would fit in the cowl. and the new 120 puts out 2.2hp but it is to long to fit the cowl with the current f/wall position
I could set the engine back inside the fuselarge (as I would have to do with a FG20 or 125) but I am trying not to.  The reason for all of this is is because the model is being built to scale F4C rules and if I can totally enclose the engine and exhaust inside the cowl I get a K bonus of 10 points

NM2K

My Feedback: (14)

I don't think that there is much difference in horsepower between engines developed in the early nineties versus those developed more recently. Yes, there is some difference, but not a large enough amount to worry with in most instances.

On the other hand, if one were to include more recent engines developed and sold by OS Engines, instead of just Saito engines, then there might be more to think about.

Also, it might be time for scale modelers to consider liquid cooling their engines when the rules are so strict concerning air cooled engine parts being displayed to the observer.


Ed Cregger

mike109

G'day

I have mostly Saito four strokes but I also have a few OS and Laser engines too and a couple of Enyas.

The Laser 80 is 92mm from bottom of mounting to top of tappet cover, the Saito 82 is 93mm so both should fit in your cowl.

I was flying my OS 81 Alpha today. It has not flown for about 8 months and it roared into life first attempt. It is swinging a rather inefficient Master Airscrew 14 x 6 prop which is very noisy but it pulled my quite large Hanger 9 Piper Pawnee into the air on about half power or less. It then happily flew around on about 1/3 throttle and I never got to full power. It would seem to be quite a powerful beast but I suspect it may be a bit too tall for your application. I have not been able to find its height. If it will fit your model, I am sure it would fly it well.

My Lasers (70, 100 and 150) are really nice engines to use and very happy to run inverted. I was worried that the high set carby on my 70 would cause fuel pressure problems if I mounted it upright and then flew the model (Kadet Senior) inverted but it runs perfectly upright and inverted with no noticeable change in tune. (Yes, I know Kadets are not supposed to fly inverted but it does. Reluctantly.)

Some other engines to consider.

At the present price of the Australian Peso relative to the UK Pound, the Lasers are actually affordable. Mr Tidey will be happy to discuss your requirements too.

Cheers from Dubbo

Mike

earlwb

You might want to consider a RCV engine, either the inline gear reduced version so you can run larger more scale sized propellers or the CD version because of its low profile. The CD version has the same vertical height of a 2 stroke engine but it is a 4 stroke engine. The gear reduced version has the cylinder pointing forward making it ideal for those narrow cowled airplanes. I have two of their 58CD engines and I like them a lot. I am planning to stick them in a twin one of these days.

blw

My Feedback: (3)

Saito lists both the 115 and 120 at 2.0 hp. The 125 is rated at 2.2 hp.

FNQFLYER

Thanks to all who contributed to my question re engine hp and size.  The RCV devices according to my data have problems with the pinnion starter gear (haven't looked at the "normal ones yet") the Lasor is to long otherwise it would be ideal, current thoughts are that the Saito 82 might do what I want
I can of course recess the firewall but that will be a last resort, so I guess I'll have to look at what will do the job for the given weight airframe.  I am still building my test a/c so the go will be to balast that model to the expected flight weight and try it out.
I have a question re glider tugs and tow releases but we'll hold that for another day
BTB people here in FNQ (Cairns OZ) we have for Australia Day and the 3rd day a row blue skies a little SE breeze and temps in high 20's / low 30's  BUT there is a cyclone a millions K's off shore

Rudolph Hart

OK,the reason i asked about maximum distance away from the engine is that i don't want to remove the cowl every time i finish flying for the day.Was thinking about mounting it to the wing centre section inside the fuse.
I have two 82's and they pack a good punch for their weight,good luck and don't worry about the plastic backplate.
Good luck with the blue skies

FNQFLYER

Thanks guys, heres what I have deduced from all the research
a/ The Laser guy is a great help but his engines are to long to fit my ideal parameters
b/ I reckon I'll need about 1.5 hp and there a lot of 1.5 (or close to) 4 strokes out there
c/ The RCV's are either to long or have some cloud over head re the pinion drive for the "odd bod" engine
d/ Considering the 1.5hp idea the Saito 82 fits the bill being 1 mm longer than ideal so it looks like that will be the way to go (good excuse to buy another engine assuming we don't have a "Great Big New Tax" soon).  I am a bit concerned can any one tell me if these engines (the 82) have plastic back plates if so is there a suitable mod available?

Now if all else fails I have a number of .60, .91, and 108 two strokes that fit the dimensional criterea but wait I haven't check YZ yet bugger

blw

My Feedback: (3)

I don't there has been any complaints about the 82 backplate. There may have been one a few years back, but it seems to be totally reliable. And, there is new one if you want it. I wouldn't worry about 82. Besides the new backplate that fits the 72 there are a couple of easy fixes for the flexing problem. I wouldn't part with either my 72 or 82.

w8ye

My Feedback: (16)

On the Saito 82, the intake tube is designed much better where it enters the head. Also, the 82 had the redesigned plastic back plate with the extra braces on it from the beginning.

As a result, the 82's are not known to have trouble with vacuum leaks at the intake/head junction.

blw

My Feedback: (3)

I have the metal backplate on a list of parts to order and I think I'll order the 82 manifold for the 72. Glad you mentioned that. I had problems with the new style backplate on it.

w8ye

My Feedback: (16)

I've changed over a half dozen of them already to the metal back plates

FNQFLYER

Ys engines, buger they don't have hp figures on the website and I think the 70 might be interesting but cannot get figures or data so will discard that idea.
Now with the 82 what prop sizes can I turn with that beast??

w8ye

My Feedback: (16)

I run a 14 X 6

blw

My Feedback: (3)

Rotorwing Nut

You are member #721

Anyone else?

earlwb

Ooooo.. club member numbers, please assign me one too.