Wait! I know this one... "Buy a genuine/ reliable O.S. engine, It's a no-brainer!"

... I knew I heard that phrase many times over the years. [8D]

I have 2 Saito 180s in service for 3 years now. All of my 4 cycle (O.S. and Saito) engines turn heavy Graupner props *balanced* chordwise and lengthwise- the correct way to balance.

... The 180's shake bad at low RPM's and at other throttle settings. I've been at this long enough to know how to properly tune an engine.

My OS engines run as smooth as a sewing machine



**** Anyway, back to the OP's choice in engine size.

IMO,

Saitos vibrate from the Torque they produce.
Compensate for it is what I do.
Bob

Right on Bob.

Another factor is the significant light weight of the engine block and 'flywheel'. Having the shakes in a large engine like the 150, 180 and 220 is the price we 'pay'.

YS 63s will give you more then enough power to fly any 40 size airframe. Great engines once you get them tuned out correctly, if you do not have any experience with YS then get someone at your club who does to help you out with them. They run great inverted as well.

Zain

So, will an unbalanced prop and/or spinner. In 4 years of prop purchases, I have not gotten one prop that did not need adjustment.

My Saito FA80, and FA91S, don't vibrate any more than my OS's.

Saito 82 great engine and never let me down

I have a Great Planes 40 size Mustang. It has an old 70 OS surpass in it. Its mounted inverted and runs great in this application. The model balanced with the battery behing the wing in oil cooler scope and needed 1/2 oz of lead in the tail. Now I have OS,Saito and YS engines. They all run good. How much lead would it have taken if I used an .82 Saito? Its much lighter than my 70. I agree get the plane first then pick an engine for it.

I got me an OS 70FS 1 for $150 NIB. I got all yall beat!

Another vote for the Saito 82. I just like a Saito. Balance the prop, follow break in instructions, and enjoy. Only $229.95

'fraid not

Quit raining on my parade here.[&o]

Saito is unloading their old engines with the plastic backplate that's why only $229. Nothing wrong with them though, i have 2 of them.

I beleive their making a replacement aluminum backplate for that application.....or maybe i had a GREAT dream.

True. Every prop needs balancing.

I think some people read my earlier post and assume Graupner props don't need balancing.... They certainly do.

Graupners are heavy and thats a good thing for larger engines.[8D]

I see this statement a lot about YS plus some odd ideas about them needing high nitro fuel. I would like to know what the difference is between tuning a YS compared to any other engine?? The regulator is almost never touched or adjusted so all you have is the high and low needles like any other engine. Brett, I got my OS 1.20 pumper for free and an OS 91 non pump for free and an older OS 70 for 100 bucks. GOTCHA!! I'm working on a saito 1.25 for free too but I think I'm just blowing smoke on that deal.[>:] Has anyone ever heard me mention how much I like free??