RC-Captain

I am not sure why you picked me to attack but I will respond as best as I can.

Anything I write is my opinion and IMO OS engines are not the most costly engines out here that's why I offered my opinion about OS engines.

Secondly have you ever heard of buying used ? I am sure it's far fetch for some to by a good used engine but I will take a used OS over a new GMS, MAGNUM and ST any day because all of the OS engines I have run great after many flights.

I hope I helped you calm down a bit.

sigrun

Huh? I didn't pick YOU to "attack". It's not about YOU nor were my comments ad hominem. They were about the contradiction. You were shouting (typing in capitals) about O.S. Even if the inquirer had not specifically pointed out that money was tight which places O.S. well down the prefer to pay pile, as I mentioned, O.S. have had their own problems with the 91FX amply documented here. Why pay twice as much if it'll still likely present problems seems a reasonable line of thought and worthy of pointing out to me? O.S. ain't the everything O.S. do is gold brand the label once represented. 46FX liner disaster exacerbated by years of denial, premature 50SX bearing failures, 91FX carburation issues...et al.

Yes, heard of it, even observed it, but been around aeromodelling long enough to know it's better to 'eat your greens' if you have to by paying the extra to buy new and avoid someone else's 'problem child'. People only boast about their successes, and I don't believe in the hardly run in only driven to church on Sundays by granny bargain used anything any more than I do in the Easter Bunny. A new engine comes with warranty, which in the US (we envy you) actually means something. A second hand one doesn't.

Aren't you the one SHOUTING? I think you unnecessarily personalised comments which weren't directed ad hominem at all. Peace pardner.

britbrat

I don't always agree with Sig -- but this time he is dead on the money. The guy said money is tight -- that means no OS in his future, particularly a used one -- they sell for stupid prices. Stay with the question & answer it -- he wanted to know if GMS were OK -- not if he should buy OS.

My experience with GMS is mixed at best -- two GMS 47's & two GMS 76's. Neither type was inspiring. The 47's were certainly powerfull, but neded carb re-work to raise reliability to only average levels. The 76's aren't even particularly powerfull, but also have issues & needed carb re-work as well.

ABELL

Too new to this hobby to comment , but from expirence of owning two Tower engines which are made by GMS I now have a super tiger and a OS and will not own anything made by GMS. Super Tiger prices are close to GMS and , at least the one I own, is very dependable

prop planter

I think you should waite until after your anger management classes before you post.[X(][:-][X(] You lose your cool way to easy and is at the very least uncalled for. Leave sig alone as he seems to have a more proffesional opion and attitude. That said, when money is tight, o.s. just isn't an option. We have had very good luck with our GMS 47s, GOOD LUCK!!!

D-LOCO

My $.02

I built an LT-25 and put a GMS 32 engine in it. Maidened it about 3 weeks ago after running 3 or 4 tank fulls of fuel thru it.

Just completed flight number 15 this morning.

Seems fine. Way overpowers the LT-25 (should of bought the GMS 25). Starts easy, idles fine and transitions to hi speed nicely. No dead stick (yet anyway). I did replace the glow plug with an A3.

I heard that these engines sometimes had manufacturing residue (metal chips, etc) inside that caused problems so I took it apart before installing it. Absolutley perfect inside with. very nice machine work.

I'm happy so far.

This Friday I'm going to maiden my 4*60 with a GMS 76. Hope it works out as well.

Dave
AMA 847123

go-kartowner

I am one who likes GMS engines. I have a .47 and a .76 and they both produce a TON of power. I had a few deadsticks with the .47 but I fixed that by buying high temp silicon and removing the carb and backplate, putting a bead of silicon around the rim and reinserting them. It now runs perfectly and it has even more power than before. The .76 started the first try out of the box and runs flawlessly. Go ahead and get the 1.20.
Karter

Buck Rogers

well iv been runing a super tiger g75 in my spitfire for ages and never had eny problems with it..i think its a great engine and not that expendsive..

Buck Rogers

ohhhh[X(] wait a sec...there was 1 bad thing about my super tiger...it had metal shavings on the top of the piston when it was new..good thing i always look befor starting new engines

Mr. Canadian

I own a GMS 47, it's a pretty good engine for it's price. Mines been through 4 crashes and still runs strong. All you have to do is seal up some of the carbulator and you've got a nice engine. GMS is good if your running low on cash and need an engine.

the_madgenius

Papa John , Like you i am pressed for money so when i needed a 90 size engine, i choose a super tigre 90 to fit into my Excelleron pattern ship, the price was right. Well it flew 2078 flights doing pattern in my aircraft, in the last 2 years, and i have now just replaced it with my first 120 4 stroke engine.In all that time the super tigre never failed me once, unless you count the twice i ran out of fuel, to cause a dead stick landing. I never had a tuning problem, and always had heaps of power. I will replace the ring in the engine and put it into my next model as i have found it to be an excellent motor.So for the price , there is my experience with Super tigres. I also own 2 51Super tigres as well , with no problem with them either.
Bill

izzy-israel-73

would you get more power out of a 0s 61?

blvdbuzzard

You can always use an ASP engine. They are the same as Magnums and I have several of them and all have been sweet engines.

http://www.hobbypartz.com/72p-108a.html

Buzz.

eiutian

I would not hesitate to buy another.

JollyPopper

My Feedback: (6)

As end users we can only credibly report on products we have used extensively. The only two GMS engines that I was closely involved with were absolutely great engines. I had a .61 on an Ace 4-60 that just ran forever with never a dead stick. I lost it one day when I suffered a dizzy spell while flying and it flew away. I was never able to find it. The other was a .47 that a close friend bought as a throw away because it was cheap and he couldn't afford an expensive engine at that time. It performed so well that it became an everyday flier for him.

zx32tt

My Feedback: (9)

I've owned 2 GMS engines, a .47 and a 1.20. I had the .47 on a LT-40, and ran many gallons of fuel thru it as the club trainer. It was probably the most trouble free engine I've ever had. The 1.20 ran well also, but I sold it and the plane it was on after only a few flights.

Tom Nied

Back in 2005, I reported here, "My GMS 47 runs great". I actually bought two at the time, immediately ran them on the test stand, and found that they ran great, on the test stand. One ended up in a Tower 40 Trainer, the other in an Avistar. I had so many dead sticks, and wasted many seasons of flying, always blaming myself and then I realised, I was wasting my time. I studied the internet for known cures, asked proficient flyers for their suggestions, modified the carburetors, finally came to my senses and got rid of them. And I've been playing with glow engines since 1967, so I have a fair amount knowledge about how to run them. Notice Tower doesn't sell them anymore, what does that tell you.

Save yourself the angst, buy anything but GMS. I change my vote to "BAD".

fliers1

I had the same problem with Sig Manufacturing Aviastar .46. I bought 2 of them a few years back. Both were extremely hard to turn over by hand. It was almost impossible to start them with an electric starter, that is until I took out the glow plug, fill the cylinder with oil and then glow fuel and only then I could turn it over with an electric starter. I did that for a long time, then replaced the glow plug and finally got them to start. I bench ran them for almost a gallon of fuel, put them on my trainers and tried but constantly failed to get a full flight on every try. They refused to run more than a few minutes before they just decided to quit. Guess what? Sig is selling them for $49.00. Wonder why so cheap? lol

fliers1

Hossfly

Funny Funny: Post 36, then a jump to post 37 about 7+ years. And it keeps moving. NEAT! I was always a Super Tiger fan until Great "Pains" took them over. Still most are excellent. I hear they are going to be deleted from the menu. While the .60s have always been good, IMO the .75 is superior. I have never had a dependable ST .90 and I have worked with them a very good amount of time. When GP took over ST, they left the small restrictor out of the carb. used for all .40 through .51. Sad business move. The carb needed that restrictor. I made them for guys that wanted such and they all ranted about how a ST .40-45-46 became a fair-headed machine.The .51 could get by without the restrictor. Never could "unner-stan" why GP just refused to stick them back in the package.
As for the GMS and such engines, they did have some problems. They were very much over-compressed. Grab a coke-can, cut a couple head gaskets, put them in their place and they changed a considerable amount for normal flying. Use of low nitro, and a 3-5% of oil mix (castor) also helped the normal sport flying. Racing models could do without the extra oil, however the fun-scale, etc. fliers sorely needed a reduction in compression, and more oil than 18%. I think I have a couple out there in the barn, still in box.
If I now wanted something new, it would be the new line of Evolution gas burners. Have to use a tad bigger engine, but the larger engine provides some extra nose weight (HA!) and much better reliability.

Now passes the next seven years, maybe we will take this subject up again.

bigedmustafa

My Feedback: (2)

The GMS 1.20 and the Evolution NX 1.00 are almost legendary as being the two most-impossible glow engines to get running reliably. Most folks who've had either of these engines won't have much nice to say about them.

I myself have had a very good experience with the GMS .47. I bought a non-remote needle valve model that ran quire well. I have found that remote needle valves and cheap engines aren't usually a good combination. My Magnum .52 XLS 2-stroke ran much more reliably when I abandoned the remote needle valve assembly on it.

If you're looking for a cheap engine that is actually good quality and will provide reliable service, you have plenty of good options:

> Super Tigre engines are powerful, reliable, and very well made. Parts availability can be spotty, and Great Planes may not be distributing them much longer
> Magnum/ASP engines are good performers and good values. Mine haven't always aged well, but I don't have any complaints for the price paid
> JBA and SK engines from KangkeUSA. If there is a true bargain still available in glow engines, this is it. Very high quality at very inexpensive prices

Hopefully the quest for a good, inexpensive glow engine will never fall too far from the front page of the Beginner's forum here at RCU.

ckangaroo70

My Feedback: (51)

I agree. Have had two SK 50 engines, a couple SK 90 engines and a couple JBA 56 engines and they have been real nice performers. Did have a crank pin break on one, but customer service took care of the repair and that engine was a real gem after that as well. I had one of those JBA 56 on a 40 size NJ One profile I built from AMA plans and it would pull that airplane out of site like a rocket. Lots of fun and a lot of dependable power for the money.

KW_Counter

can't hold a tune any better than Kris Kristofferson.

Kris holds one better than Johnny Cash and wrote better songs.
Love to listen to both of them.

KW_Counter

refinno

I have three GMS engines... a .47 in a cub, a .60 in a Pica Cessna 182, and a .60 in a DR1 Tripe... all run really well... good power and they idle nice... the one thing you need to know is it tells you to initially open the needle valve 2 1/2 turns... you really need to start at about 4 - 5 turns.... otherwise they run really nice... especially the two .60's