2W0EPI

I cannot understand why 4 stroke glow actually sell, the power output of a 4 stroke glow is round about 1/2 that of a 2 stroke glow which is about 1/2 the price of a 4 stroke glow. I can think of 2 advantages of 4 stroke glow, these are good fuel economy and long engine life however 4 strokes have a lot to go wrong with respect to the opening and closing of valves operation, 2 strokes have less moving parts which is desirable. I notice OS has introduced a gas/petrol glow that is it has a glow plug just like 2 stroke glow but it works with gas/petrol

I think if migrating from glow 2 stroke, would be looking to transition into 2 stroke gas/petrol with spark plug and ignition system.Unfortunately, the lowest cc for 2 stroke gas/petrol is around 10cc which is still a bit big.

init4fun

You did not list one of the biggest advantages of 4 stroke VS 2 stroke, , , , , , SOUND !

Believe me I love and run all types of engines (and yes motors too) in my planes, and of the engines I run, the 4 strokes sound better. In a nutshell, the 4 stroke don't have that "flying chainsaw" scream of the 2 stroke, a sound that seems particularly attuned to pissing off the flying field's neighbors......

Now aren't ya glad ya asked?

David John Davis

...and they all sound effing awful!

tedsander

You have not then encountered a Y.S. 1.20/1.40 4 stroke. Lots more power than any available glow 2 stroke, or many petrol engines of similar size.
But....gave up on mine as the ~$6-7 USD per 8-10 min flight at current glow fuel prices was getting hard to justify.

2W0EPI

Yep, I have to agree with you, however, I just want to point out that sound does not impact performance.

David John Davis

I have a few two-stroke glows but only one is fitted in a model, the club's trainer! As for four strokes being less powerful, fit a bigger four stroke! It's that simple!

init4fun

And I want to point out that "performance" isn't always everyone in the hobby's ultimate carrot on the end of a stick. Are you the guy that I've already had a conversation with in a different thread about "fun" not coming at the very ragged edge of just how fast one can make a model aircraft fly ?

Try this "performance" scenario on for size;

Your screaming 2 stroke pisses off the field's neighbors SO badly that you get the field shut down, VS your 4 stroke not emitting the shrill whine doesn't bring the negative attention.
Now, tell me, , , which engine has "performed" better????

Joseph Frost

I love the sound of 4-strokes, always used them rather than screeming 2-strokes despite slight less power, so all you have to do is upsize a bit. The key is regular service/maintenance of taps check and adjustments I do on regular bases. I use them mainly in multi powered toys.

Giant 12 kilo twin cyl. 4-stroke Boxer sonding awesome.

Twin 4-stroke powered B-airliner by Frosty in my younger days, still ticking sweet after regular service.

Four 4-strokes sounding even better.

TheEdge

My Feedback: (788)

Damn that is one fine Lanc.

Joseph Frost

TX, (took me ~1000 hours to build) tail heavy as a brick at 12kg, needed lot of nose probe balast to fix it, flew well after, later de-commissioned and moved it 4-strokes to

Sweet sound of 4-stroke Herc.

Now as E-power.
"C-130/Herc", still flying it but now as E power with 2kilo more thrust, and LOL.

daveopam

My Feedback: (9)

Having flown both I will say this. On a 3D type plane I prefer a 4stroke using glow. Replacing a .45-.50 two stroke with a Saito .82 made a better 3D plane IMHO. Throttle response was better being the main difference. The .82 had a shorter spool up time and made better torque on the low end. When you are hanging on the prop at eye level every second counts. Not saying it can't be done with a good two stroke. Just giving my preference.

David

2W0EPI

For me, migration from 2 stroke glow towards 2 stroke gas/petrol means two important advantages can be gained, the first is precise controlled ignition timing with auto advance at high rpm and secondly, gas/petrol is considerably cheaper than nitro glow fuel. Ignition timing on either 2 or 4 stroke glow is at best erratic.

daveopam

My Feedback: (9)

Currently everything I fly now is gas/petrol. I still own a few glow powered planes but haven't flown them in years. I'll never go back to glow but gas is not practical for a .40 size airframe either.

david

2W0EPI

That is correct, about 10cc and below belongs to glow, the smallest 2 stroke gas/petrol engine, that I know about, is the NGH9 (9cc), but I've been told elsewhere that NGH engines are not so good?

David John Davis

They still sound bloody awful!

2W0EPI

That is very true, it's an annoying whine but, for a lower cost entry into rc plane flying, the 0.46 cu.in glow 2 stroke engine is king. I would also like to point out that a 6hp petrol 4 stroke 2kW generator system sells for around £240 whilst a 4 stroke petrol rotary rc engine can have a asking price of about £4500, clearly ridiculous, even if it does sound better.

David John Davis

You are misinformed.

The cheapest petrol four stroke engine costs £280 from Just Engines. I would not buy one myself because I have several four stroke glows currently sitting in their boxes doing nothing. https://www.justengines.co.uk/shop/p...v=11aedd0e4327

People cite the lower price of petrol as the reason for going over to two stroke petrol engines as if we are running a fleet of diesel trucks instead of flying a few toy aeroplanes once in a while. However, modern Chinese two strokes fitted with a standard silencer not only sound bloody awful, they are so noisy that they could be the cause of losing flying fields. If you must run a flying chainsaw engine, at least fit an effective silencer. Zimmermann have a good reputation: https://zimmermannschalldaempfer.de/...--muffler.html

As for your remarks about the 46 two stroke glow being the entry level engine for beginners you are absolutely right. If you crash a model powered by a four stroke engine you may well have a big repair bill on your hands and second hand two stroke glows sell for peanuts these days. I have one in a Seagull Boomerang. I use it as an advanced trainer with novice pilots. I would not put one of my beloved four strokes or even my Enya 50 in the clumsy hands of a beginner!

slindsay

I'll have to say I do like the sound of a 4 stroke engine, I only have two at this time. My back ground is 2 stroke and have a good number of them in my shop. However I've been trying to move to gas 2 stroke engines due to the cost of fuel these days. I first bought a 15cc to mount in an old Astrohog, then acquired a 10cc and I think I'll use the 10cc for the Hog. I've started a build (I have been very slow with that) of a Carl Goldberg Super Chipmunk and I have the 15cc mounted at this point. I've also acquired an old biplane the Lazy Ace, 76" wing I think. HeHe, at first I purchased a twin 30cc but I may revert to a twin 20cc for the Ace. Anyway for me I believe gasoline engines are my future. I am not interested in electrics at all. I'm just an old retired guy that likes to bore holes in the sky on weekends. And 3D is not in my vocabulary, but I do like to watch.

sherm

2W0EPI

That's the direction we must all move in for lower cost and precise ignition timing reasons. I see 4 stroke gas on offer but the expense and power droop is just too much.

Cheers

Telemaster Sales UK

I'll stick with my glows.

I already have a fair bit of fuel in stock, besides we're not running a fleet of diesel trucksare we? We are fueling little engines to have some fun on the weekends. I don't suppose you'll get very fat on the amount you will save going over from glow to petrol.

Besides, unless they are fitted wiuth a decent, read expensive, silencer, they will sound bloody awful and are likely to loose flying fields in noise sensitive areas.

2W0EPI

Highly unlikely given the amount of business and revenue generated by the rc community.

init4fun

Shirley you can't be serious ?

Noise complaints from neighbors have lost plenty of flying fields over the years, and as to revenue generated by our hobby? Freakin STAMP COLLECTORS generate more revenue than we do

David John Davis

In the immortal words of John McEnroe, "YOU CANNOT BE SERIOUS!!!"

2W0EPI

A lot has been said about 4 stroke nitro/petrol but what about 2 stroke glow gas/petrol? Here/s the one such example

https://www.align-trex.co.uk/nitro-e...-silencer.html

Power output is up there, but it uses a special O.S. developed glow plug?
What about it's cost?

David John Davis

Being an OS it should work well but they're not popular. I've never seen one on a flying field.

It's your money but for slightly less you could buy one of these and run it on the recommended new 7% oil mix.Laser 180 | Laser Engines