Hi Guys,

I'm a relatively new flyer (about 9 months). I've flown my trainer with a 2 stroke, Four Star with a OS 91 FS and my Somethin Extra with a OS 70 FS. On the table now is a CG Ultimate. I've been trying for a month to decide which engine to get for it. All I know is that if WILL be a 4 stroke. I've heard good things about the 120's (OS, Saito etc) but the engine rumored to give all out performance is the YS 120. Even the plans show a YS 120 in the nose. So here's my question, is the YS too much trouble for the average sport flyer? I fly a day or two a week usually. I enjoy the hobby but am not competition oriented at all. I just have fun. With all the tinkering I hear YS's need, and the pressurized fuel tanks potentially giving some trouble, is it a wise choice for an average flyer? Would I be better off with a "normal" 120 - OS or Saito?

Sorry for the long post, I just wanted to give you all the background for the question and why I'm asking.

Who's flying the CG Ultimate and what engine are you using? What performace are you getting?

Best,
Harold

No, no problem at all for average. The complaints come mostly from below average flyers or people who have NEVER owned one

I have seen the 120FZ on a CG Ultimate and it was outstanding !
Put the tank back at the balance point and enjoy some nice flying without the CG shift from forward tank placement ! Dubro and the hayes tanks work well . Reinforcing the tank with some nylon strapping does no harm . The only tanks I have seen let go were the Great Planes brand .
A Saito 150 would be close to the YS 120 in power ,but not overall running.

If you are going to use a Y-S 120, you had better hurry up and get it if you want a new one. They have discontinued it and brought out a sport version of the 140 to replace it. A used 120 would still be a viable choice if you wanted one.

Jim

Maybe I'm coming from out in left field but I do know people that started out with a 91 4 cycle in the Ultimate then went to a 120. After flying with the 120's went back to the 91's because they liked the way it handled better with the lighter engine. Now weather they corrected the balance I don't know, their planes could have been to nose heavy.
The Goldberg is not as big as the other 120 Ultimates on the market and if you could keep it's weight around 7 1/2 lbs. it should be fine with a 91, great sport flying biplane. I will let you know this summer I'm going to finish mine (I hope), I'm planning on going with a YS 91 (about the same weight and power as the OS 120 so what was my point)???

Lady flyer I disagree with you that anyone that disagrees with you about the YS engines is a below average sport flier or never run one. You are totaly out of line in both points. Your opinion on the YS engines is just that your opinion, and we all have one. I for one have been flying RC since 1970 and have flown quite a few 2 strokes and 4 strokes over the years and that includes the YS engine. The YS engine is a good engine for what it was built for. Power and performance, and with that comes some some benefits and some problems. I for one fly for fun and performance and the absolute demand for power is not a factor with me. With that pressurized fuel system which works great can be also a major cause of problems over time. You develop a air leak in that system and you can have real headache trying to find it. I have seen fellow flyers ready to pull their hair out trying to figure out why their YS engine won't run. I for one will say this for the average sport flyer that does not need or demand the absolute in power and performance go with something other than YS. This is from experience with the YS engines and others that I have flown and is my opinion which we all have.

My first 4 stroke was YS 120 SF on a CG Ultimate. I too was an average flyer until I started having fun with this plane/engine combo.

However, something that I would consider would be the availability/cost of parts in the long run if the above statement is true.

I second the idea about moving the tank to straddle the c of g. Also, change the wires to 4-40, go pull-pull on the rudder, and go with the 2 aileron servo config.

I am a new owner, year or so of a YS 63. I wished I had got one for my second engine. Once you know the basics they are not too bad. I have had an air leak on a 2 cycle drive me nuts before, what would be different about a four stroke?? One has to learn the ropes and it does not appear any harder to me on the YS.

I am not setting a fire here nor wish to offend anyone, the YS fired right up out of the box with little or no messing with and I have not had a moments problem. I can't really speak for the larger engines.

just my 2cents

I fly an older YS 1.20 (the SF - "Big Valve") in my CG Ultimate. I can't imagine a more fun combo! As for your question about the YS engines for an "average" guy, I would not hesitate to recommend one, IF the guy can read directions and FOLLOW them. If a person does that, then in my experience, there is no real "Fiddle Factor" to the YS engines. Many of the guys that I have seen at our field that do a lot of "fiddling" with their YS are running either the wrong fuel (low Nitro, low oil) the wrong plug (stick with OS type "F" or the YS plug), or have been adjusting the REGULATOR (they often SWEAR it is a pump) and needle valves in full turn increments. Sometimes they didn'y look closely at the directions and have the fuel lines hooked up wrong. Often I see all these problems in one engine!

Anyway, this is not to knock other brands of engines, as I own and fly other stuff too. I just wanted to address the questions you asked.

Have fun..

Lee

punkey71,
Having owned and currently owning 6 YS engines, I would HIGHLY recommend them. The reason for using the YS's for me is simple, reliability! They are not completely set&forget but I don't worry nearly as much about the aircraft completing its flight if powered by a YS. Most of our, (my son & I), experience has been with the 1.20's but also have a .91.
The "tinkering" is minimal and well worth the time and effort. Just keep the basic "maintenance" parts on hand, (plungers, springs, diaphrams and OS F plugs - they cost more but you'll probably use -1- all season!
My personnal opinion
Steve
Puckett Model Aviation

RLD hit the nail on the head. Most of the problems I see people having with YS engines is caused by operator error and not the fault of the engine.

Follow the instructions and if you are unsure of what is going on, phone up YS Performance and ask. If they are not abused they are virtually trouble free engines.

I finally burnt my first OS F plug, 3 years of running on a 140L

Waco , If you handle engines as carefully as you READ postings and TWIST other's words you may have helped make my point !
I said MOSTLY as opposed to your misquoted ANYONE!
Thank you .


Propwash Don,
You may have a point , the 91 would be a good bet too . The flyer at our field started out with an Enya 120R GP on his Ultimate and had a lot of engine trouble so he went to the 120 FZ ,It flew real well . A 140FZ came along and he couldn't resist. After a few flights he decided the 140 was WAY too much and the 120 is now back up front . I'll bet the 91 would be plenty for most

The Saito 120 has almost the same power as the YS 91 and doesn't cost MUCH more. It is the most durable of the Saito engines that share the same case size . It is a pretty good runner but cannot match the mid range strength or transiton of the YS91FZ.
I LOVE Saitos If I had never owned Saitos I wouldn't realize just how good YS engines really are

You are on the right track looking at 4 strokes. The cost of feeding a fuel slurper like a Webra 120 or a Moki monster hardly makes up for the $20 or $40 you will spend for a good 4 stroke 1

Harold.....Punkey71 or whatever you go by here,

Just a few years back the CG Ultimate was one of the most recomended IMAC planes around, especially for an IMAC newbie. Actually, all of the Goldberg aerobatic planes were highly recomended, and one of the most popular power plants for those planes was the Webra 1.20. I know, it's not a 4-cycle engine, and based on what you fly now it looks like you're a 4-cycle kind of guy, but you can't beat the bang for the buck ratio of the Webra 1.20.

BTW, a Moki 1.35 would be awfully nice in that plane too and it just loves cheap 0% nitro fuel. Use Sig or Byron FAI blend and a K&B 1L plug. The Y.S. on the other hand, likes drink an expensive 20% fuel blended just for Y.S. engines and uses expensive plugs too. Maybe cost of opperation should be considered, but that's for you to decide.

Here's a thought...... The RCS 1.40 gasoline burner puts out about the same power as a 1.20 glow engine and it's not a lot heavier than these other engines. Now we're talking really cheap fuel, less mess, lower idle, and the added relibality of spark ignition. (Some people will argue that last point, but that's been my experience with spark ignition)

Not much Y.S. advice.....sorry about that. I've owned 2 (.91AC & 1.20SC) and I didn't really feel they were worth the extra expense.

Wiz

thanks everyone....it seems the concensus is there is no consensus! :-)

I think I will go with an OS or Saito 120 ... but I appreciate all the help nonetheless....

Best,
Harold

Horold
I have either a NIB Saito FA-120S Golden Knight (Version 2000) sharp looking engine or a NIB OS 120 Surpass III (pumper, new model, the good one) I would be willing to sell either one for $300.00 shipped free in lower 48. e-mail me = [email protected]