davewallace

My Feedback: (29)

Hello,
I came across this buy now deal on Ebay. Sounds like a real bargin for one of you guys.

http://cgi.ebay.com/31cc-Ryobi-Gas-E...QQcmdZViewItem

Dave

Note: I have no connection to this item in anyway.

cu. in.

Dave,

Thanks for the info. My main concern would be the weight at 4.3 lb. For argument's sake, lets say that this Ryobi has the same power as an OS 160FX (26cc). The OS 160FX plus stock muffler weighs 2.7 lb:

http://www2.towerhobbies.com/cgi-bin...p?&I=LXUM83&P=

This kit certainly provides cheap flying, but its application would be limited IMHO.

Bruce

av8tor1977

My Feedback: (6)

If you set it up with electronic ignition, it will weigh a good bit less than 4.3 lbs., but it will never have near the power of an OS 1.60. Possibly near the power of a four stroke 120.

AV8TOR

davewallace

My Feedback: (29)

Hi Bruce,
You have some good points, but there are many people out there who would like a good deal on a heavy mag ignition 2 ring Ryobi. This appears to be it. I know it isn't a DA50, but it doesen't cost $600 either.

Dave

cu. in.

AV8TOR suggested that this $70.00 Ryobi is closer in power to a 120 rather than a 160 two stroke. After checking some RPM readings in the glow engines forum, I agree. So, lets compare it to an OS 120AX:

http://www2.towerhobbies.com/cgi-bin...p?&I=LXLGJ0&P=

The OS 120AX with muffler (no 90* adapter) weighs 1.8 lbs. This is 2.5 lb. less that the 4.3 lb. Ryobi. Two OS 120AX engines at 3.6 lb. still weigh less than the 4.3 lb. Ryobi. A DA 50 at 3.1 lb. weighs less than this Ryobi. This Ryobi has a terrible power-to-weight ratio, and that means that any aircraft that you can buy today, ARFs mostly, will provide a boring flying experience. I just think this hobby should be fun, and that R/C aircraft should be fun and exciting to fly. This Ryobi certainly isn't my idea of fun and exciting.

I agree that this kit provides rock-bottom pricing for an engine, but because of its poor performance, it is my contention that this engine, as is, represents a lousy investment.

Could this engine be a candidate for gas/glow operation? I would think that with a minimal investment in time and money, engine weight would be reduced while power would be increased due to glow fuel content. Just a thought.

Bruce

av8tor1977

My Feedback: (6)

Hi,

For one thing, I was talking about power, not weight in that comparison. For another, the comparison in power was to a 1.20 Four Stroke, not two stroke.

These engines work well in planes that need added nose weight anyway. I have one running on gas glow in a big Tiger Moth biplane and it does fine and I'm happy with it. An added benefit is that it will run on gasoline, or gas/glow, which is cheaper than pure glow fuel, and it will run on 2 to 3% oil in the mix so there is no mess to clean off the plane. It is not an engine that I would ever choose for a 3D plane.

AV8TOR

av8tor1977

My Feedback: (6)

On a different side, I have Echo/Kioritz engines that weigh just over 2.5 lbs. including the engine mount that swing a 16 x 8 prop at over 9000 rpms. I have one on a GSP Katana 140 and it flies super! The engine cost me 10 bucks used, and performs great. I don't fly 3D myself, but I'm sure if I went to a lower pitch prop this combo would do it. As it is the vertical is basically unlimited.

The Ryobi does have a poor power to weight ratio, but it has it's applications.

AV8TOR

captinjohn

Another thought...you can get a Ryobi for about next to nothing or free. Convert it to a lightweight glow engine and you will have power then. If you mix your own fuel....the cost of that gets much better. Remember if you get a engine about free...you can then afford to mix a lot of fuel to run it. Just a Idea. Capt,n

cu. in.

AV8TOR,

Thank you for mentioning the big Tiger Moth application. I can see where the Ryobi would work well in this aircraft. When I first read about this engine this morning, I couldn't imagine what aircraft you could use it in, and now I can.

captinjohn,

It looks like this $70.00 Ryobi, or a free Ryobi, is about the lowest cost option available in the conversion field. Compared with $250.00 to $300.00 OS engines, you can indeed afford a lot of glow fuel. I have a background in the manufacturing field and have a pretty good idea of what castings and bar stock cost, and IMHO, OS engines are way overpriced based on actual manufacturing cost. Also, OS is no longer providing the quality that they used to. For example, the OS 120AX actually has a serious carburetor flaw that has been discussed recently in the glow engine forum. In the case of the 120AX, spending a lot of money is no assurance that you will receive a trouble-free powerful engine.

Thank you for everybody's input.

Bruce

davewallace

My Feedback: (29)

I just checked Ebay and the introductory price of $69 is over in four hours. They are now offering the Ryobi kit for $98 buy now. Has anyone bought one?

Dave

tkg

My Feedback: (1)

There are a whole lot of fliers who just enjoy an afternoon of flying around in circles and for excitement they will do a loop. . For some of them flying in circles is really exciting ( for guys in the pits too). For Not everybody is into 3-d
So what ever floats your boat.

captinjohn

Take a look...this could even be made to weigh less. What more could you ask for? Capt,n

cu. in.

tkg,

"for guys in the pits too". I hate those low-level circles too.

captinjohn,

It looks like you made several changes to your Ryobi:
1. Glow plug/adapter
2. Removed flywheel
3. New mount
4. New muffler
5. New prop shaft.
6. Other?

I would guess that your Ryobi weighs somewhere between 3.5 to 4.0 lb. without prop or spinner? Do you have an aircraft for it yet?

Thanks,

Bruce

rcuser004

My Feedback: (287)

I have (2) near new Ryobi dual ring engines listed at $ 149.00 for the two shipped.

Mike

[img][/img]

Bill Rademacher

My Feedback: (77)

I have seen this thread soooomany times.

Everything in an airplane is a package. It's the package that is the goal. Right motor, right airplane, right wing loading, etc.

Yes, the ryobis are relatively heavy even when trimmed down (and you can trim them way way down).

Why do I fly one? Because it was 3 inches at it's widest point, cheap, and I like to say "it's a ryobi with electronic ignition - you know, a wead eater".

I liked the challenge of getting a good flying airplane with the unlikely conversion motor.

And, I was successfull. It rocks!

Volfy

My Feedback: (23)

Hey!!! That's my Ryobi 31cc.

That was a single-ring Ryobi (older version) - my very first conversion engine! In that pic, I've got it set up on glow fuel (90/5/5 methanol/castor/nitro). Attached is another pic showing what was on the other end of the test bench sawhorse. Ahh... brings back some hair flapping, smoke blowing, ear deafening, neighbor complainin' memories...

Prop hub and glow plug adapter are from CH ignitions. Motor Mount and (not visible) carb adapter plate are from Carr Precision. B&B Muffler. I've had it running with up to 15% nitro and 10% oil (it makes more power with more oil, probably better combustion seal) and I remember it ripped the crap out of the 18x8 MA compared to an OS 1.60FX. Not bad for an engine package that barely cracked $100. Weight was right at 3lbs IIRC. Ended up selling that engine on RCU.

Later I did buy another Ryobi 31cc - actually a Bloens curve shaft trimmer - this time a twin-ring new version, when Lowes had it on sale for $49.95 brand new a few Xmas back. It was one of the last batch of 31cc with separate bolt-on flywheel guard. It is a classic by now. I won't be parting with it any time soon and will be saving it for a project where only a slim profile engine like the Ryobi will do.

captinjohn

cu in: That is not my Ryobi....I think it belongs to Volfy. It is a nice conversion he done. Capt,n

cu. in.

Bill, Volfy, Captin,

Thank you for your input. I spend most of my time in the RCU Glow and Gas engine forums, not Conversions, and it just seemed to me that this $70.00 kit was marginal at best. I happen to like high performance machinery, so I guess it's a case of different "strokes" for different folks.

Thanks again,

Bruce