Central just got off the phone with YS Japan, November or December for the new YS115. That is what they said today. I am using the last production YS110 in a Focus Sport. I have another one on the bench, was hoping to put the new YS115 on the front. Looks like it may be a while, and who know's if Nov. Dec. will be the date.

I am not an expert here, and realize the advantage's of YS power. I am now considering the OS 110 or 120 pumped. Opinion's appreciated.

Thanks,

Vince

110 120

YS115
Displacement 18.73cc
Bore 30.4mm
Stroke 25.8mm
Weight 730g

OS 120 Pumper: - $465
Bore: 30.4mm (1.20")
Weight-With Muffler: 35.3oz (1000g)

OS110 pumper - $480
Bore: 1.20" (30.4mm)
Stroke: 0.98" (24.8mm)
Weight: 21.5oz (610g)
Muffler Weight: 2.5oz (72g)

Tuff choice. The os110 weighs less than the YS115. The os120 swing the same prop as the YS110. I think the os120 would be too heavy. I would check the Focus Sport thread to see if anyone is using an OS120 or OS110. There is only a $15 difference in price.

Why not get another YS 1.10? There are plently of good used engines to be had, or people that have bought a new motor and never taken it out of the box.

Did you think about a two stroke, like the 1.20AX?

Might be nice to have two different styles of power, rather than your primary plane with a monster YS and a backup plane with a less powerful OS 4-stroke.

After running my YS, I've propped my 120AX down to a 16x6. Gives me much quicker throttle response, still plenty of speed with ~10k rpm. Cost a lot less, too

Thanks for the details Randy. I am using the latest YS110 in another Focus Sport. I was also advised to put a YS91 on the front. Couple other's said the OS110 pumped verson will haul the mail.

Vince

i have both the Saito125 and 120 AX. the Saitor would be a good choice if have lots of 20-30% nitro fuel. the AX is very strong and very light (lightest 120) bone stock will pull an APC16x8 at 8,600 or put a Jett 120 muffler on it and hit 9,600. close to same rpm with Xoar 18x6

I happen to have run both the YS110S and the Saito 125 on that very same aircraft.
Each was run on 30% Wildcat, all synthetic. The mounting holes and mounting hole to back of prop dimension are identical. Only the servo/throttle linkage needs to change sides. With mufflers in place (stock) they are the same weight

Power = no contest. The YS was consistently 1000 rpm better on a 15x8 APC. The YS when flown a little will go to a 15x10. The Saito stops at the 15x8. The 15x10 is too much for it.

Tuning, well that is a no contest also.
The Saito sets up very quickly.
The YS is a royal PITA to set up but once you do get it right it has power to spare.
I had each engine mounted on the same Hyde mount with different cowls cut out to match the engine.

If you want to do the Focus Sport justice in the air, it has to be the YS.
I've since gone all electric but that was my last Glow set up.

BTW, I have not exaggerated one bit !
Not on the set up !! - and not on the power either.

Unless you want aerobatic limitations (the 125 will give unlimited vertical but does NOT begin to have the authority of the YS.) you should either find an available YS110S or simply wait for even more power and the 115.
Hopefully the new regulator set up on the 115 will make set up easier. Trust me, that will not be hard to do. []

I'd wait for the 115 (same mounting dimensions as the 110) but it is your choice.

If your two copies of YS110 are working fine, I would like to suggest to run them, hard. You could reduce the flying envelop, and use a slower cruising speed for level fight.

Dave at YS services suggested the use of 14X10 apc for pattern.

Thanks for info. Using 14 X 10 on the 110. You guy's convinced me, the 115 has been on backorder for about a year, two more month's is easy time.

Vince

The YS PITA mentioned above was my experience. After it wadded up the second $30 spinner, I finally sold it for an OS 1.20 AX. It has the typical two stroke throttle curve. But more power with less hassle on 10% fuel. Running it on a 16-8, with the tank on the cg with no pump and no fuel draw problems.

I recommend and use an OS 120AX with a Perry 2 cycle pump and a 17 X 6 APC pattern prop. The engine runs great with lots of power and good throttle response. I use 10% nitro fuel. The whole package is a lot cheaper and easier to maintain than a YS or an OS 4 stroke. You also have no need for a soft mount or a nose ring. This setup is simple and it works.

Found a NIB 110, FZ110S, just like the one I am using now.

Vince

Hi guys.

Just want to share my experience with this engine.

engine: OS120AX
configuration: inverted
tank: tettra 500 at the CG @ 1/2 inch above the carb, 2 lines only
fuel: cosmo 20% nitro - 18% oil synthetic
pump: none
prop: APC 16 x 8

comments:

Back pressure was more than enough. Had to lean out low end by 3/4 turn. Can be used to practice P-11 schedule.
It starts like any other OS engine does, easily.

More stick time than wrench time.

More power and Big Thanks to JeffRCU for the help.

I have the same good results with my OS 120AX. I have the engine in a Venus II. Originally the tank was just behind the firewall and with a MAC muffler, the preassure was just fine. I got sick of re-trimming the airplane as fuel was used and I kept forgetting to re-trim for the next flight. Now I had to use lots of up elevator until I could get my hand away from the stick to trim it. I moved the tank back to the CG and installed a Perry pump. All is great now. I use a 17X6 APC pattern prop and I am very pleased with that combo. I also had to lean my low end at least 1/2 turn initially and another 1/2 turn after I installed the pump.