What size engine have people been putting in the Ryans? I understand that a good 90 four stroke will fly these nicely. What is your opinion?

I have a YS 91 in mine, and it flies very scale like. Just wish I knew how to downsize a pic of it to post here.

O.S 120 f/s in mine. love it

put two flights on it tonite as a matter of fact.

OS 120 III Pump. I used 90 degree header and flex pipe. No holes in that beautiful cowl. Flies smooth plenty of power.

BobHH

I just installed the OS 1.20 in mine tonight. Everyone says it's MORE than enough. Fits very nicely in the cowl too. I have athread in this forum showing my engine/muffler installation if you're interested. Not too many others seem to care judging by the response I've gotten

Jeff

Jeff--

I think it is a very clean install.

Thanks,
Sneakypete

Everyone has told me about their 120's. Has anyone flown it with a 91 fs?
Thanks,
Sneakypete

Sneakypete,

From what the various reviews I have read on the Ryan (MAN, MA, RCM, et. al.) reported they all used the 91 4-stroke. From those flight reports they all say it flies 'scale like'. So what does that mean? It means it flies nicely but it is not going to burn up the sky. It will fly on the wing though and NOT the prop. And this is the way it should be. However, that being said, most guys are used to overpowering their planes and depend on that extra power to help them out of a bad situation. Putting a 90 4 stroker in the Ryan will require that you actually fly and plan your manuevers rather than just twizzle the sticks around.

Now you might ask; "Jeff, you're an accomplished pilot that can fly most anything why did YOU put an OS 1.20 on yours? " There are several reasons.

1. it is nice to have that EXTRA power just in case. The fact that I have a 1.20 doesn't mean I'll be blasting around at full throttle all the time. Far from it. It's more than enough to fly it at half stick. I do know how to manage the throttle. But knowing I have a reserve there when I need it brings extra peace of mind.

2. Nose weight. I was suspicious the Ryan was going to need some nose weight and after installing the engine last night and cheching the CG I was right. My saying is 'useful weight is better than dead weight'. The useful weight in my case is the extra power of the 1.20 The tail on the Ryan is sturdy which translates to 'heavy'. Even though the servos are mounted forward by the wing there is still a lot of mass back there. I even have a 5 cell 1500mAh sub-C pack up front.

2. Price. I was able to get a pumped OS 1.20 for $320. That's a bargain in my book. It was only $100 more than a non-pumped OS 91 4-stroke. So I figured for an extra $100 why not.

In my opinion if you use a 90 it will fly. But you'll be flying the wing. Which is 'scale-like'. If that way of flying is comfortable with you then I say go for it.

hth

Jeff

I just flew my STA for the 1st time this weekend.

I am not a ARF fan , but I have to admit that it flies
really well and looks good in the air.

I have a old OS 120 FS in mine and it has much more
power than it really needs. I fly it for the most part at
1/2 throttle and to get this plane to land, the idle has to
be quite low.

If I had a .90 kicking around I think I would prefer that
power plant over the .120

Roby

I also elected to place an OS 120 FS on my STA-M. I have yet to fly it but I am sure after reading these comments I will enjoy it.

As far as the engine goes one other thing needs taken into consideration and that is the fuel tank location, I understand everyone has to use a pump so as not to flood the carb due to tank placement.

As far as the 120 muffler configuration here is a nice tip that will save those extra $$ on that flex pipe. Here is what I did. I took the original 45 degree header and placed it in a vise. I then cut the threaded area just behind the pipe its self with a hack saw. I then placed the 90 degree header on the engine and used the piece that I cut as a nipple to join the muffler to the header, which came out perfect, also saving some weight up front. The locking nut was left centered on the custom made nipple so as to tighten muffler to header. I used the high temp RTV gold instead of lock tight as it has a higher locking bond.

I have a question for you 120 FS users. What size fuel tank are you using? and if it be the 16 oz, how much flight time are you getting out of it? Mine is ready for its maiden flight and should maiden this coming weekend.


Thanks
Randy

Blackie,

Nice tip on the muffler. I've gotten suggestions in another post of mine that a flex pipe is needed because of vibration. That this vibration will lead to fatigue since there's no stress relief like a flex pipe will give. I don't buy into that personally since every flex pipe I've ever had has cracked.

Let us know how the ST-M flies with your configuration. Mine is still a few weeks away. I have to add flying wires and detail out the cockpits, add the pilots, etc. still. I have the stock 14oz tank in mine. From other posts I've made it seems that 14oz will give me plenty of flying time so you 16oz tank should be OK.

Jeff

jbrundt,

I'm not quite sure I follow you on the stress relief statement. Can you please be more specific.

I am trying to figure out how a flex pipe reduces vibration other then using the original configuration without either 90 degree or flex pipe. Does this mean that the plane as a whole will suffer fatigue without the flex pipe?

I am just trying to make since out of this.


Nice to hear on the tank size and yes I will be glad to report my maiden flight and flights after.

Thanks
Randy

Blackie,

Ref this thread: http://www.rcuniverse.com/showthread...804&forumid=57


The inference from that post is that without any ability of the muffler system to 'flex' there will be fatigue cracking from engine vibration of the muffler/header pipe. The thinking is that the flex pipe will have give and prevent fatigue cracks from it being too rigid. I don't buy into this. I've had many muffler systems over the years and the only cracking I've experienced in the exhaust system is from using a flex pipe. And in those cases the flex pipe is the part that fails. The OS header pipes are very robust and have a good wall thickness to prevent this.

The whole airframe will be fine. I didn't mean to cause you any undue worry. If you're using the stock engine mount provided or another isolation type engine mount things'll be fine.

hth

Jefff

OK I just went and took a look at your configuration looks nice. The nipple configuration I came up with allows me the right amount of distance to place the muffler spout right out through the very bottom opening already present in the cawl, No cawl cutting what so ever with no rubbing on any part of the cawl/plane. Since this configuration is quite shorter then what you used, I believe it will help on the vibration issue. I just wish I had saw your post and responded to it before you cut the cawl.

If I get the chance I will take some pictures but I think you have a good idea of what I have.

Randy

jbrundt,

One more thing I noticed in these pictures that you have not yet cut the other holes in the cawl. The two holes on the very bottom facing opposite of each other I drilled out also to help with air circulation, not sure if you were planing to drill those out.

Blackie,

I did cut those other holes out. The pictures in the post are from before the final mounting. You can see other pics on my ST-M web page on my website. I'm not too upset about the muffler exiting where it does right now. I'm happy I can get it all inside the cowl to begin with

My worries will all disappear when I find that it runs cool enough and there's no overheating. That will make me a happy camper.

Jeff

I have a Saito 100 on my 90 size edge and if I am not mistaking it gets much hotter then the OS so I don't think we will have to worry to much about heat. At least I hope not.

Heres an example. One of the instructors has a custom built cap which is running the OS 1.20 FS I am running the Saito 100 as I mentioned above. His engine has no problem with the typical rubber extension you find in your LH attached to the end of his muffler. However that same type of rubber extension mounted to the end of my Saito 100 would not last 20 min in the air before it melted off. I have tried everything to keep it on even drilling a screw with RTV gold, no luck. The Saito is exiting inside the cawl which leaves a mess but nothing I can do. Weight is an issue so I can place anymore weight up front.

Although his engine is mounted sideways, his cawl was a scratch built wooden cawl that allows air to flow over the head.

I guess the only way to really find out is to give it a try.

Randy

Randy,
I'm using an old 120FS which is a non pump engine.

I had to lower the tank just a bit to allow proper running
of the inverted engine. The relocation of the tank took about
20 min. all I did was carefully cut away the original tank
support just enough to allow the tank to be lowered as
far down as it will go. Not a big deal but poor engineering
in the design.

I don't remember if I used the supplied tank. I think I did.

As far as flight time.............10 min easy......most of the time
I was at 1/2 throttle or less.

The only problem I seem to be having is on the landings.
I put it down on the mains with no problem as the tail starts
to settle down the bouncing begins. Looks like I'll have to slow
it down a bit more and 3 point it in.


Roby

I got the flying wires done. Here's a pic. More to come plus details on my web page......

Why not a little extra suds ? Sure, the Ryan will fly with a .90 4-popper, or even an .75 2-stroke.
But it's a good sized plane...and not light.
I have a STA in the pile, with a Magnum 1.20 4-pop.

If some extra weight is needed up front, it would be silly (IMHO) to under-power the craft. I heard somewhere....that in powered-planes, the key word is "power".

I don't see anything wrong with some great verticle....a nice hammer-head...some monster loops. I think a guy with the .90, and the extra needed weight....would be wishen' he put in the 1.20.

jbrundt,

After looking at your pics I noticed you went with the stock fuel tank, I've never had any luck with those stopper tanks. They always seem to leak. I have now started replacing those stock stopper fuel tanks with the square tanks such as the Hayes or GP fuel tank. Not sure why they didn't place the square type in the Ryan *shrugs*

I then seal that round hole up with silicone.

Randy