I'm just moving from 2 to 4 stroke from now on and would like some valuable feedback on what to buy.
I was thinking about the Magnun XL_52RFS which is $140 comparing to OS FS .52 and Thunder F54S that are both around $185.

What you guys say?

Nilo

I'm in love with my new Saito .56FS. It has given me no problems and sounds GREAT on my J-3 Cub.

I'm thinking about my 1st 4 stroke too. One question: is the manufacture's HP rating relivant compaired to 40 size 2 strokes. i.e. I see a .46 2c with 1.5 HP and a .56 4c with 0.9. Does this really matter?

Horsepower claims by manufacturers are about as good as T1Ts on a boar hog.
(Excuse my french)

I like the Saito 56 also, light, economical and does a fine job.

Basically it a a Ford vs. Chevy vs. Mopar thing.

Good, that's what I was hoping to hear. Thanks.

However, while the HP numbers are bogus, a .54 4-stroke does not put out the power of a .46 2-stroke. Most guys who want that level of power go for a .70 4-stroke.

Saito 56 sounds highly recomended. I have a Midwest Sukoi that's been half built for 10 years for it.

Yes, personally, I prefer a 70 4c for a 40 size plane.

I completely agree with the Saito .56! I have one one an Ultra Stick 40 and it is powered PERFECTLY for what I want it to do! Using an APC 12X6 with Cool Power 10% 2 stroke fuel (still running it in fully) I am getting 10,000 RPM at peak! To make this even better, I have barely used half a gallon of gas thru it!!!!! Once I get the first gallon of fuel thru the engine, I am planning on switching to cool power 15% 4 stroke fuel! Am I looking forward to that day!!!!

Anyway, another motor you may want to look into, if this is your first 4 stroke, woul.d be the Magnum .61 RFS. It has nearly 20% more power than the Magnum .56 RFS and weights just about the same!! Now for a reason why I say this! I have one! Now this is the good reason for the Magnum! I had this engine on a few different airplanes, with it's last one being a SPAD trainer i used to train people on. The SPAD weighted in at 7.5 lbs dry and the Magnum pulled it around very well. No it didn't have a unlimited vertical, but it did have some get up and go! I had the engine crashed a number of times (normally letting a student get WAY to far into a problem to let them see if they can get it out.) Anyway, I started to have idle and top end problems with it. Called Magnum up and discussed the problem, and they merely said "Send it in!" I called about a week later to check on it and got the shock of my life!! IT WAS BEING REPLACED AT NO CHARGE!!!!! To make it better, the engine was about a year out of waruntee and they didn't even blink! Now that is customer service! OH, another thing, the eninge they sent was already run in by the engine techs!

Now all of this being said, I have to ask you a question! What do you plan to use this engine for and what tyype of flight performance do you expect? This can make giving advise to you on 4 strokes easier to figure out!

Thanks,

Reg

PS Stay away from the Thunder 4! Way too heavy for too little power!

I have 2 Saito 56's they run great. I also have an OS 52 and it runs great also.

ys 63 by all means

agree... the ys62 is the best in class but it's not as friendly as the O.S. 52...

I woulnt consider the YS is in any 50 size 4 stroke class. Nor would I reconmend one to a 1st time 4 stroke buyer. That being said, I dont believe there are any bad 4 strokes currently being manufatured today in this class rang. You'll be happy with any you choose. The magnum is a great price 4 banger if you want low investment for a good runner. Saitos are my personal choice. Love all my .56s. Works well on 40 size airframes. The 72 could be a better choice depending on the airframe and flying style. Just watch landing gear height issues on 40 size birds.

ys engines are harder to tune but it's easy to get the hang of it. when you have your engine tuned right, it will be more reliable in every way than the competition and have more power too. ys engines are competition four strokes meaning they are made to compete with other two strokes of the same class. ys engines will also have a better throttle transition and a better inverted idle because the low end affects the idle mixture ONLY instead of everything at once until full throttle. the low end controls the idle mixture so you just lean it out until it won't load no matter which way the engine is mounted, the regulator screw affects the midrange more than the other adjustments (becasue the low end is idle only and the high end is full throttle only) but you will have to compensate a bit for the increased-decreased flow with the high and low end. trust me. get the 63 and you will not be dissapointed. i used to be an os supporter but i will never leave ys for four strokes. i have really found the best.

I have a number of YS engines, including a few .63s. While they are awsome running engines, they are indeed built for performance. I have run them on 15% nitro, but they don't perform like they are meant too with the lower nitro. 20% and above is better to get their expected performance. I do not consider them in this 50 size class. More likely in a 90 size. For first time users, they are a bit more advance in tuning and plumbing, but not enormously difficult, just different than other 4 strokes. That is why I would think an aspirated engine would be a better beginning engine. Isn't Hobby people running a sale on Magnums right now?

Thanks for all help.
I'm planning to use this engine for sure on a scale in the future, probably a WW2 bird, but not sure which one yet. Meanwhile, I'm going to use in my 40 size trainner that need an engine since I returned the evo 46 that was on it.
I already use a RCV on my piper cub and will need another one for my tucano.

Based on my plans for it, any changes to what you guys recommend for the .50 range? The Magnum .61 and Saito .56 are both under 200 but the YS .63 is $288[X(]

By the way, what you suggest for a .90 size 4 stroke (for the Tucano). I was thinking about the new RCV91CD that is still to be launched but I'm not sure when and may never happen.Below some research I did for .90 range.

RCV-- RCV91CD--$229.00
OS-- FS91-II-- $229.99
Thunder-- F-91S-- $189.99
Magnum-- XL91RFS-- $189.99
Saito-- FA91S-- $239.99


Nilo

I have Saito's. I have run them for many years. I do not own any other brand 4 bangers. If money is a consideration I would say the Magnum. If not I say Saito for your first 4 stroker. There are lots of people who use them and help is readily available.

For the other I would say Saito 91 or 100. Or if available a YS 90. They should give you the power you need. Once again money is an issue, YS's are not cheap.

Good luck and enjoy whatever engine you choose

Gees guys, he asked about .50 size and we're up to 100's already!
Any of the main manufacturers are o.k. really in the .50 size.
The YS .53 is a super powerhouse and probably wouldn't be the ideal choice for mounting in a trainer though.
As already said, (quote)......"its a Chevy, v Ford v Mopar sort of thing..."

Nilo, the engine I would recommend for a warbird would be the Magnum .61 RFS or a Saito .72. The resoning behind this is that most warbirds need a lot of power to make them fly well. The .56 Saito that I own cannot yet hover a 5.3 lb Ultra stick, at least with the fuel I am currently using that is! Now, the reson I recomend these engines is that if you decide to get into something more aerobatic later on, then you already have the engine to power a .40 size plane GREATLY!!!

I am not by any means saying that a .50 size Magnum or Saito wouldn't power it! I am just suggesting that you think down the road! For flying a warbird, you have excess power for takeoff and to power out of mistakes with these 2 engines! For cruise and realistic scale flight, you can simply reduce throttle! This gives and added benifit of longer flight times!!!

Either .56 or .72 Saito OR .61RFS Magnum should give you GREAT performance from what you have said you want! You may just want to go with the slightly larger ones for later on and some added insurance during flying!

Thanks,

Reg

if this thing is going on a trainer than i would say get the lightest and cheapest one. for that matter, for a trainer, get a two stroke., they are lighter and cheaper and you won't really notice a performance difference because the trainer is not designed to harness performance.

Yo Woody he asked about a 90 size 4 stroke. Keep up man!!

Any comments on the Enya 50 ?

Enya makes a .53 4 stroke. It is a great runner. Will last a lifetime. Perhaps a bit heavier than some others though.