Ok, I'm getting ready to make the plunge into 4 strokes, having been flying for about a year. I've had good experiences with 2 stroke OS, Webra, Thunder Tiger, MVVS. I can tune a 2 stroke, the low end and the high end quite easily.

My question is should my first 4 stroke be a YS? I crave its power and light weight but I've heard how touchy they can be. Or would Saito give me an easier time? What do you guys think?

~Deltaforce

DF:

My personal preference is the Saito line, but if you are willing to read the instructions (and follow them) you should have no problem with a YS as your first 4s engine.

The 2s/4s business is no problem, or not much of one anyway. Where you might be better served with something less complicated to start is the fuel system. Unless you do exactly as instructed, and make an effort to understand what you're doing, setting the carb and regulator can drive you up the wall. Be prepared to spend a while with the engine on a stand until you get comfortable with it.

Bill.

PS: Strongly advise a tachometer, if you don't have one already. With greater familiarity with 4s it will become less important. wr.

Go with the Saito you will not be sorry, I have had the YS engines although they might have a little more power they need at least 20% nitro to get it , the fuel system is lot more complicated and the engine weight is alot more than the Saito . Buy the Saito mount it on your plane and fly the hell out of it day after day the Saito is dependable and trouble free. BTW.. I sold my YS engines and now fly only Saito four strokes. Lidman

Sorry Bill I sent this to you instead of Deltaforce I guess I shoud of gone to bed earlier.. Lidman

I read this and wasn't going to reply, but since the score is 2-0 in favor of Saito I thought I'd better help even the score.

All I've personally run is YS, and they are the only 4 stroke I ever plan on buying. I am in charge of a fleet of 8 planes at my research job here at college and they all have Saitos, so I do have plenty of experience with them even though I've never owned one myself. YS's fuel system, though more complicated, really gives it the edge on power. It's a big edge too! Saito guys may come and say their Saito turns almost the same RPM with the same prop but they are probably using 30% nitro to get the same numbers as YS on 20%. True YS needs 20% to really run nicely, but it IS worth it. My 91FZ turns an APC 15x6 at 9,900 RPM very reliably; over 10k on a nice cool day. Can any Saito guys say their 91 will do that with the same fuel? Doubtful. I'd run up to a 61 2-stroke before buying my YS 91FZ and was frankly a bit scared of the power it had when I first ran it up. I was in awe... and I loved it.

If you can tune an MVVS engine to sing well you can tune a YS without problem. Spend the little extra cash and get the YS. You'll kick yourself later if you don't.

Carl

DeltaForce,
I totally agree with Carl.E ! YS engines out perform all other 4-stroke that are out in the market today. I would even say that on 10% the YS would either equal, or out perform other 4-strokes out there with them being ran on 20%.

Also, My YS 110 FZ runs very well on 10%, and idles reliably too! I have recorded some RPM figures at http://www.rcuniverse.com/forum/YS11...1902708/tm.htm so check them out. Remember, these figures are with 10% fuel and in summer conditions IE: 80 degrees and above!

By the best, buy YS!!!!!!!

Ltr Dys and better Wys,
Dennis

The age old fight between YS and Saito..... Compare prices YS 110 to Saito 150, YS 63 to Saito 90, YS 140 to Saito 200.... thats also the power comparison. Also if you assemble your tank as per mfgr with 1 fuel line and 1 press line, you should not have a tank problem. The only thing added is a T in each line for fueling and press release.
Saito's are great motors and YS's are Awesome so either way, you cant go wrong.

Have 20 jr experience with all kinds of engines. Have had no trouble with any brand.
This morning tried to run my first YS. Could not get it running.
See my post on the ys support forum: http://www.rcuniverse.com/forum/YS11...1998741/tm.htm
I'm sure I will find out what is wrong, but my first conclusion is that it is fore some reason not as simple as a Saito or any other four stroke

Having run Saito's, YS's and OS four stroke, I'll add my thoughts. As I said, I have run different versions of all three makes of four stroke engines, and have had some very fine versions of all three. With that said, most of the folks that I have seen complaining about YS engines being "touchy" to set up, either "A" - Don't read/follow the directions, or "B" - learned on another make of four stroke engines and so assume any other engine that uses DIFFERENT (note I didn't say more difficult) set-ups and proceedures "must" be trickier to use. I will grant a person that YS engines ARE different to set up, tune, and run, BUT, if used the way they are designed, I have found mine to be every bit as simple to use as my other four strokes. And THEN there is the power and reliablity issue. My YS's have been tops in both areas for me. Do I have to use different fuel, plugs, and in some cases even props...yes, but then that is what the engines were designed to use!

I guess to me, if you have not already learned how to set up "other" brands of four strokes, and you start with a YS and learn it's correct set-up and handling, you might actually have an advantage over an "old timer", who has to re-learn certain aspects of engine set up when they get their first YS!

Just my two cents worth...

Lee

My 1st 4-strk was a YS. A .91FZ to be exact. I think you will be fine buying a YS as your first 4-strk. If you live in a high elevation area, the YS is better. I own Saito and OS engines also, so I can personally speak for them all motors. They all are great. Saitos and OS are less complicated to tune, but the YS is a true power house. I just ordered A YS 1.10 for my Funtana S 90. If you budget will allow you to buy a YS then go YS, but if your pocket isn't too deep a Saito or OS will do fine. It really all depends on what type of flying you are trying to accomplish and with what type of plane. General flying and over powering a 40 or 60 size plane, the Saito and OS are great. For acrobatic 40 to 120 size planes (3D especially), the YS is a better choice IMO. More power to pull these planes around and out of risky situations, plus the fuel tank can be mounted over the CG. The YS engines have a type of supercharger pump that will pull the fuel to the motor. Saito and OS can both do this if you add a optional external pump which cost more money and has to be mounted, so just get a YS from the start.

The Saito is lighter and cheaper than the YS and OS, but the YS is heavier, stronger and more expensive than both. Did I mention it is stronger than both? The weight difference is no problem for the YS. It will only affect your CG which can be corrected easily.

The Saito does have a longer warranty. Each motor has it's pro's and con's, but dollar for dollar, the YS is a better deal, but it does cost more. Some people only buy Saito, some only buy OS and some only buy YS. They have their reasons. I have tried them all and would say the YS is #1 because it is the strongest, Saito #2 because of it's weight, OS #3 because it is heavier than the Saito but has the same power as the OS.

I guarantee, if you decide to buy a YS, you will buy another one for another plane. That is a proven fact. The power and sound are very exclusive to that motor. Like the sound of a Harley is known when you hear it.

I don't see why not. Might as well start out on the right side of the bed. I agree with what most people have said about YS four stroke above. To me, YS 4 strokes are the most reliable, the most powerful, and the easiest to tune. I have not had a single deadstick with a YS ever since I started using them. On average, it took me roughly two minutes to get any YS four stroke to purr like a kitten. I cannot seem to duplicate the same feat on a Saito or an OS 4-stroke. YS touchy? You got to be kidding me. I believe 99% of YS engine problems stem from the incompetency of the engine operator. Buy a YS 4 stroke and there is a good chance you won't be buying another brand again.

Saito four strokes are not necessary lighter than YS. Keep in mind that the weight figures given on websites for Saito engines do not include the weight of the muffler, prop washer, and prop nuts. Throw those in, and the total weight ballons up significantly. For instance, the Saito 72 with muffler is heavier than the YS 63S with muffler. The Saito 150 weighs 33.7 oz with muffler and prop nuts. The YS 110FZ weighs only 25.6 oz with muffler and prop nuts, yet it puts out almost as much power as the Saito 150.

In terms of sound, nothing beats a YS four stroke, not even a Saito.

I would go w/ either a Saito or OS for 1st 4 stroke. One drawback of YS is the requirement for 20/20 fuel. You can save some money on fuel by buying a Laser 4 stroke engine which runs great on 0-5% nitro fuel.

Tried to run my first YS this weekend, I did not succeed. In my 20jr experience have had all brands of engines 2 and 4 stroke that gave me no trouble.
So I thought tha a YS would not beat me but it did. My conclusion (based on only two hours fiddling) is that it might be a superior engine but also can cause more trouble than any other engine.
If you just want to fly but do not need the best, go for another brand.

Just what RLDIII said in Post #7 above:

20 years experience with other brands means little.

I've kinda been through the gambit on the 4-strokes. Started out with a Saito .80
(old style) which cured me from buying any more of "those".

Went into the Magnum and OS line (all .91's )....all good. Easy break-in....
good idle, super reliable, easy to tune....already at this point....Saitos....n/g.

Bought a 1.20 YS from Central on sale before the conversion.....and a couple
.91's and a .63....on the last run of the .91's. I had a .91 OS in a WM Dago Red
Mustang (old Style OS ) and it was sweet.

Changed the motor out, and put in one of the YS .91 FZ's....(OMG)....set
the engine at the Fact. specs....,.1 and 1/2 turns on both needles. Fuel dots,
and tank proper.

I haven't touched the YS all season. It runs better every lap. I think now I need
to give 1/4 turn out on the low end.....the idles getting too rich. Other than that,
it's easier to run than even the Magnum.

FBD.

YS is a very trouble free engine. All I did was set the high end and it has run 6 gallons without trouble. The YS needs more nitro than Saito? That's not true. Both engines run better on higher nitro. It's just that many people run Saitos on 15% just because they want to save some money. The Saitos will benefit from 20/20 as well as the YS.

Joe

My YS .63 ran perfectly right out of the box! I have used it for three years now and I have never had to touch the low end adjustment. Always a perfect idle. I initially ran 15% fuel for most of a season with not 1 problem at all. I now run Wildcat 30% Helimix and most people are astounded to hear that the engine is "only" a .63!

help please,
ive had a few 4 strokes and never had a problem tuning.i now have a ys 110.when i start it per instructions it idls ok when i rev it up it runs rough ans shaters the spinner. happened twice so far.leaning out dosent seem yo help.any sugestions
thanks larry [email protected]

you might have it too lean if you are throwing the prop'

what prop are you using?

what fuel

how many turns are the high and low needles at?

have you touched the regulator screw?

how many tanks of fuel do you have through the engine?

if you answer those questions someone might be able to help

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Actually, YS four-strokes are easy to tune when they are operating properly. When they are not operating properly, no one can tune them at all. <G>

Be warned that the regulator diaphragm and a few other parts (plunger/spring) will need to be changed out every once in a while. If it gets more involved than that, send it back for servicing. Life is too short to waste on trying to fix it yourself. There are no streaming sources of tech/update bulletins for end users. Yes, the engines are that complicated.

You should get a few months of trouble free operation that will be heaven-like in its bliss. If you truly get addicted to this much performance, do yourself a favor and buy a couple more engines. You'll have one to fly, one to build with/backup and one in transit to or from YS for maintenance. Performance costs and this is just part of the normal YS drill - if you fly a lot. I know, you'll hear from guys that fly one engine for six months to a year (how many times? - they don't say) and will swear that these engines are just as reliable as OS, etc. Baloney. I've flown YS engines, tuned YS engines for friends for over thirty years now. I'm from Missouri - show me.

I'm not downing YS one little bit. I'm just saying that flying the best comes with a price - as one would expect.


Ed Cregger

YS are awsome engines when they are running right. They tend to have a LOT more fuel system problems. Sooner or later you will get to experience the joys of a tank rupture
(hopefully not inside an expensive airplane). You tend to become very familliar with the disassembly and cleaning of the regulator/carburetor. Many pattern flyers end up with two because one of them seems to live at YS Performance. Standard fourstrokes may be less powerful but they are easier to live with.

Lar, you cannot use a plastic spinner with a fourstroke, it will shatter every time, maybe not right away but it will shatter in time.

--------------


YS is top dawg of the four-strokes in power and tractability. No doubt.

While I am a Saito enthusiast, I do not see where they are one whit better than OS - just different.

I own all brands of four-strokes, or have, at one time or another, with the exception of a Thunder Tiger. And I'm working on getting one of those too.

Owning a bunch of engines doesn't make me an expert. What I'm trying to say is that I'm not taken with just one brand of engine to the exclusion of all others. To me, they all have advantages and disadvantages.


Ed Cregger