How do you like your O.S. 4 Stroke Engines?

What sort of problems did you experience with them?

My first 4 stroke was a 91 OS and I am still using it. It runs great requires almost no tuning after being set. I usually check the valves 4 times a year. It makes good power and is pretty fuel eff but..... When I was shopping for new engines I picked up a Saito. They are lighter for the same size and make more power for a giving displacement than an OS and run just as nice.

Ihave an OS FS-40, FS-61 ad a Saito FA-45 All great engines.

I've had them for almost 20 years.

The FS-40 is on my step-son's Eagle II

I have an FL-70 that I just love... I will say though that a little more money will buy you a much more powerful Saito 72.

Only problem I have with OS is they don't make a 180, or at least I don't know of one!

I own nine OS 4-strokes of various sizes...

I'll give them up when you pry my cold, dead fingers from around them.

Looks like OS 4 stroke's are pretty well liked!

Not!!! I wouldn't have the FL-70 even if it were given to me free. I've had exactly one OS engine that had the air bleed low end adjustment, and exactly one is all I will ever have again too. [:@] I'll never have another one with the air bleed, that's for sure.

Ken

Ken, don't hold back, tell us how you really feel!

I've got 3 OS 4 strokes, 2 FS-30s and an FS-70 II. One of the .30s hasn't been run, but the other .30 and the .70 both run great.

Looks like O.S Engines will never sponser RC Ken!

Oh don't get me wrong, it's only the FL-70 that I wouldn't have (well, the LA engines too. same reason). But almost every other engine I own is an OS!!! I have 1 25 FSR, 1 25 FX, 2 40 FSR's, 4 46 FX's, 2 46 AX's,1 FS-52 4-stroke, 3 61 FX's, 1 91 FX, 1 FS-91 4-stroke, and 1 FS 120 4-stroke. I love OS engines, just not the ones with air bleed carbs!!!!

Ken

The FL isn't as bad as you'd think. The think I like least about them is instead of having a key for the thrust washer, they have a pin. Kind of a cheap setup. The biggest problem I have with any of my 4 strokes is the vibration ... especially on a light / 3d setup. I had an OS 120 on a cheap barely balsa F4 ... vibrated the thing to death before it ever left the ground. I have an FL that is doing the same thing to an Accel Pitts S. I'm not a real fan of an air bleed carb either, but I'd use my FL before I would my G75.

WOW! [sm=eek.gif] Ken I think that's the most excited I've ever seen you man!!! Until I read you second post I was wondering what happened to you. I was gonna ask how could you not like the 91 and the 120 4-stroker? They just plain ROCK!! You explained that so its all good.

Hello; I have one of each size of the surpass series at least. The ones I use the most are the 4 26's I have. I used a 48 for years on a midwest Suhkoi, and a 70 on my seamaster. And the 91 on an ultimate and an estra 300. I've gone over to Saito too, and now use them exclusively, from 30 to 150. Power to weight ratio allows me to fly lighter planes, also the Saito s are quieter.

Have you ever had a O.S. FL-70 RC 4-Stroke & if so what were the problems with it ?

I've had two OS 52 four strokes, along with a Magnum 52 four stroke, a Mag 70 and now a Mag 91. The only engine of the bunch to give me trouble is the Mag 52. The OS 52 are and were sweet engines. I lost one, along with the plane, behind our flying field. It joined four other planes lost out there in the last few years. I am really hooked on both the OS and the Mag four strokes. I have another Mag 91 on back order, an OS 1.20 pumper, used, that I have yet to run, a Saito 45, and a Thunder Tiger 90 four stroke also used but yet to run by me. I rebuilt the Saito and it is sweet running. Yep, I'm hooked on four strokes.

Don

Would you settle for a 200?
http://www2.towerhobbies.com/cgi-bin...p?&I=LXPRL4&P=

wow! that 200 is a monster!

anyway love O.S. i've owned, a couple 32SX, 46FX and FS-30S, FS-52S, FS-70S, FS91(P and not P), FS-120 (P and not P), FS-60 open rocker. All of them have been spectacular. They are truly "mount and motor" kind of engines. True that pound for pound my YS-63 YS-140 DZ may be stronger... but they are dang finicky. O.S. is the toyota (or lexus) of RC engines.

the only problems i have with OS is that they aren't cheap and parts aren't always easy to come by here in Taiwan.

As I stated earlier, I LOVE OS engines, but personally, a 120 is the largest glow engine that I would own.

Once you get above that, I go gasoline - More power, cheaper fuel

My first 4 stroke was an OS 120 Surpass III and it gave me no problems at all. It just ran like a champ and had great sound. I then got a YS 140dz, and hold on tight! The difference is huge. Many say they are hard to tune, and I dont really agree with that. I'd just say they are different to tune. Once you figure them out, YS engines run just as easily and just as great as OS. I wouldn't recommend one as your first 4 stroke, but maybe a 2nd or third.

I did love my OS 4 stroke though and all my 2 stroke OS engines.