RE: 2 Stroke V. 4 Stroke
 

I have two Saitos four strokes, one is inverted and the other is not.
They sell a special glow plug with a little tab to prevent the element to get fuel in the inverted engine.
Is still an F size but will prevent the flooding.

RE: 2 Stroke V. 4 Stroke
 

You're talking about an idle bar plug.

Idle bars are used to prevent fuel spray from hitting the glow element.

They are rarely used or required now-a-days.

I doubt they help inverted engines, as the only problem really involves flooding or killing the glow plug element with fuel.
An idle bar does not help or prevent that.

A longer plug can help, but it too can become flooded with fuel. The hollow where the element sits can be filled with fuel.

Your best bet is to use a longer plug, and not prime the engine before starting.

RE: 2 Stroke V. 4 Stroke
 

Used engines have never brought in anything close to the price you will pay when new, doesn't mater if it's gas, glow, two or four strokes but yes, the prices of used glow engines have fallen even more. My feeling is, if I was just getting into the hobby today I wouldn't bother with a glow engine on planes from 60 size on up. Gas is cheaper to operate, easier to set up and doesn't require any needle twisting when we have big weather changes. Think about how nice it is to not have to clean up a snot machine after a day at the field.
I have been into the hobby long enough to have a number of glow engines, most all four strokes, OS and YS. When a new YS is around $450.00 and a DLE 30 is about $300.00
it doesn't take a lot of thought to pick out what new engine I will buy. I get my glow fuel on sale for about $15.00 a gallon but a gallon of gas mix is about $3.50. Glow engines aren't going away any time soon but I can see them not being used very often in the future.
I have been given most of my engines, then I just rebuild them, it's cheap and easy so I will still be using glow for years to come. I may go back to blending my own fuel again but I will still have my glows.

RE: 2 Stroke V. 4 Stroke
 

i love 4 strokes.... OS and Saito have been good to me. I have one magnum it runs ok but not nearly as good as my others...


if you have run 2 strokes for a few years, you'll be happy with the sound of a 4 stroke... just prop it right in the 8500-10000 range is where i try to stay...

RE: 2 Stroke V. 4 Stroke
 

My Magnums have been flawless, but I find the needles to be VERY sensitive on them.

1/8-1/4 turn is the difference between an engine that will not run at ALL to one that runs perfectly.

Finding that small area can be a bear for a novice.

RE: 2 Stroke V. 4 Stroke
 

the problem with mine is getting a super low reliable idle..

RE: 2 Stroke V. 4 Stroke
 

Start with a prop that has a more mass, like an APC prop. Also opt for a lower pitch ( so you can leave the engine at a slightly higher idle ) at first until it is run in.

Once you've run a gallon through the engine swap out the props and return. You should then get a nice idle around 1800 RPM.

RE: 2 Stroke V. 4 Stroke
 

i already have over propped it... im running a vess 15x6 on a 91... i have it on a 8ft Telemaster... its a really nice combo..

i might go in on the low end...but that probably wont be for a while, i really dont fly it unless i have someone to train

RE: 2 Stroke V. 4 Stroke
 

Give a 16X6 APC or a Master Air Screw a try. The added weight really does smooth out the idle. I'm in no way a fan of the MAS props but a nice heavy K series often helps out that idle on the Magnums.

RE: 2 Stroke V. 4 Stroke
 

Just adding some random thoughts ...

I have used mid-sized 2 & 4 strokes. Fav 2 - OS. Fav 4 - Saito & YS.

I've noticed that the 4's seem to be wetter as seen during post flight clean-up than their 2-stroke counterparts. In some cases the front of the engine case is wet - front bearing "venting" (?). The 4's have a crankcase vent (bit of fuel line a couple of inches long) that will drip off combusted fuel that has collected in the crank. The 4's carb mouth (Saito) is pointed towards the bottom of the case whereas the 2's carb mouth is pointed up.

(near) Inverted mounting can result in lube collecting in the rocker covers. Some inventive types have tapped and mounted a muffler "vent tube" into the bottom of the cover and vented with a bit of fuel line (maybe this ranks in there with anal-retentive behaviour - don't know)

The throttle control location is (usually) different as the 2's carb is located up front while the 4's are behind the case.

For a similar displacement the 2's are more powerful (HP) than the 4's. Also 2's may be a bit heavier.

4's need a locking nut as well as the primary prop nut to help protect from the 4 throwing a prop.

My Saitos are very sensitive to needle positions. I'm at 5900 feet. One click on the HS needle or 1/8 turn for the LS needle can make a big difference.

RE: 2 Stroke V. 4 Stroke
 

That's a big prop for a .91 Gray?

RE: 2 Stroke V. 4 Stroke
 

I have 20 tanks of fuel through a new saito 56. So far, it has been fantastic. I sometimes touch the needle if it requires but its only 2 maybe 3 clicks. I had a saito 100 that had a problem from the factory, they repaired it for free and now thats run great. No deadsticks yet, and saitos are all I run. I do have OS 91 pumped that I'm putting in my new airplane, it should be just as good as the saitos.

Nothing beats flying alone at the field with no other airplanes and the sound of saitos!

Jason

RE: 2 Stroke V. 4 Stroke
 

your problem is most likely because you engine is not fully broken in. magnums take about 3-4 gallons to breakin but once that is done they will run with the $300 saito and os engines.
my magnum .52 took about 3 gallons for the idle to drop from 2500-3000 down to 1800 but now it runs like a top, patience is the key.

RE: 2 Stroke V. 4 Stroke
 

Augie, it's a huge prop for a .91 and not the best of choice for most people. The MAS prop is crap but the added weight will smooth out an idle. I don't use them myself, I have a bunch but I just don't like them. I ran the 16x6 and 16x4 APC on a Kaos with a OS .91 4s and I run the same props on a Hots with a YS 1.10. The reason for the big props on these two planes was because I like my planes to fly slower but pull more for verticle stunts. I try to never mention a prop size to anyone but I did this time just for the OP to test and see if it would help with his idle problem. Most 60 size planes don't have the ground clearence for a 16 inch prop and I'm not sure if a Magnum will pull one that big. For most .91 4s engines I stay in the 14 or 15 inch range but it depends on the plane. The Hots and Kaos are the only two I have used the long prop on that made the plane fly the way I wanted.;)

RE: 2 Stroke V. 4 Stroke
 

No you misunderstood, I said a prop with MORE MASS, not an OVERSIZED prop.

These are two completely different things.

A prop with more mass has more angular momentum, which helps the engine maintain a better and lower idle.

This is why the Evolution engines add a 2oz flywheel to their PTS line, to help maintain a slow and reliable idle.

You can get the same effect with an APC prop, which has the re-inforced resin...

I find the plastic Master Airscrew props to be a bit too light to add any benefits for a reliable idle....

I've swapped in APC props of the same size for an MAS when I've seen someone fighting their engine trying to get a good idle... much to the pilots amazement their problems disappear... I then tell them they can put their old prop back on after they've run a gallon through the engine.

RE: 2 Stroke V. 4 Stroke
 

[quote]ORIGINAL: Gray Beard


In my experience the fuel regulator is what gets most new YS owners in trouble. Since many of them are "supercharged" that fuel reg can be confusing. That being said, the newer ones seem to be set up pretty good from the factory and as long as you don't get overly fiddly with them, aren't much of a problem. I do know my .63 does NOT like to get too hot. Had it in a P-51 and it literally dropped the valve guides into the engine...twice. It will never be in a tighly cowled airframe again. But boy did it ever work awesome when it did!

My fuel of choice on all my 4 bangers is Powermaster YS/Saito 20/20. Sure glad I hoarded me a supply before they went away for a while...

RE: 2 Stroke V. 4 Stroke
 

I love them both! I like the 4-stroke for the sound and top end power, and I like the 2-stroke for their simplicity and high rpm. I have a Saito FA150GK and a 1983-1984 O.S. FS120 (before Surpass) 4-stroke and they are both fantastic! I think the other reason why I bought a couple of 4-strokes (other than the sound) is I like to tinker and maintain my engines from time to time as a seperate hobby.

All the rest of my engines are 2-stroke. I own 6 engines all together.



Pete

RE: 2 Stroke V. 4 Stroke
 

Once I got my first 4 stroke, there was no looking back. ;) I have Saitos, Magnums and OS, and like them all. The Magnum for the price and good mileage, the Saitos because of the looks and sound and the OS because it's an OS! IMO, the OS's are probably the best but I prefer the Saito's even though they slobber like a pig. They just remind me of an old Harley. They leak oil, but they are just so cool! :D

RE: 2 Stroke V. 4 Stroke
 

I find that a "slobbering" Saito tends to be a mistuned engine.

The Saitos run well even when grossly out of tune. They often come from the factory rediculously rich ( 11 turns out in a couple of mine ).

I've seen people complain about their fuel consumption, I walk up, lean out the engine ( usually greatly ) and the slobbering and fuel consumption issues disappear....

I like the OS's and Magnums too, but the Saitos seem to be the most forgiving.

RE: 2 Stroke V. 4 Stroke
 

I have many 4-strokes of just about every brand except YS.

OS .70 Great engine, runs out of the box, but a little expensive

Thunder Tiger .75. Runs great. Needed some break-in, but hasn't failed me yet. Had it in a sport plane, but now in a Fairchile 24 scale turning a 14-6 prop.

Saito .56, .72, two .91s. All run good. Took some break-in to run really well. All have been in seaplanes.

Magnum .30, .52, .70, .80, .91, 1.20. Takes some break-in. Best 4-stroke for the money. A copy of the OS Surpass Series. Excellent service. We dunked a pair of .52s in the water and the bearings went out later on another plane. We sent them in, stating we had them under water. Both were fixed for free.

I like 4-strokes on seaplanes for their reliability and good idle.

When the vent line dumps a lot of oil, the engine is either not fully broken in or it is out of adjustment. When they aren't broken-in well, there'll be some oil blow by the ring and go out the vent. Once the ring gets good and seated, most of the oil venting will stop.

Figure 2 times the 2-stroke displacement for 4-stroke size (except for YS and they are potent, but expensive). As an example, I just took a 4-stroke .91 off an Ultra Stick 60 so my flying buddy could put it in a scale plane. I replaced it with a Tower .75 2-stroke. With the .91, the US60 flies nice, but not too much vertical. With the .75 2-stroke, it has unlimited vertical-straight up forever. Oh, yeah, I used the same prop, a Master Airscrew 14-6, on both engines. I didn't have a good 13" prop for the .75, so I took the 14-6 off the .91 4-stroke and bolted it on the .75. Go big on 4-strokes and they are not heavy, especially Saitos.

I run 10% Omega, castor blend in everything.

RE: 2 Stroke V. 4 Stroke
 

I heard Magnum doesn't last as long. Seems that O.S. Saito and YS is the leader of the pack for dependability and service life. Is that a rumor or is it true from what you know? Sounds like Magnum has great customer service. Better than Hobbico from what I just read?


Pete

RE: 2 Stroke V. 4 Stroke
 

Marketing types will throw out all sorts of innuendos, which get picked up by people rationalizing their own purchases over something else, and that gets repeated over and over again via the grapevine...

In practice my Magnums have lasted as long as my OS and Saitos.... going on well over seven years of solid flying.

I've also picked up some older Magnum engines from Junk ending boxes, cleaned them up, and put them on planes I've built for newcomers into the hobby. These engines are many years old and still run well, without bearing changes, etc.

Heck I've yet to have ANY engine I've purchased from any manufacturer "wear out"... and when I've been given engines that the owner claims are "worn out", I find that they bearings are usually gummed up, requiring only a relatively simple cleaning.

The only downside I've found to the Magnums is that I find the needles to be VERY sensitve... 1/4 turn is the difference between an engine that will not run at all, to one that runs perfectly.

Some say that they need a few gallons of fuel to break in... I find that a flight or two is all that is needed.

If anything I find that OS engine valve pushrods are a BIT more prone to gum up over time, but this is a pretty easy fix and not a huge problem.

RE: 2 Stroke V. 4 Stroke
 

Thank you for your info. I didn't know that. I'll keep that in mind when I buy another engine, but right now I have enough. Two of my 4-strokes are'nt in a plane yet. I'll give Magnum a shot.


It's hard to get the truth about products sometimes.


Pete

RE: 2 Stroke V. 4 Stroke
 

And I find them total junk. They really don't seem to last very long and aren't worth the time to even rebuild. When I get them in a trade I either give them away or use them for parts. I have some OS and YS engines that have been in constant use before a lot of people on RCU knew how to talk or walk. I just pulled a YS 1.20 that has been in constant service sense 1988. I'm going to just give it a new ring and lap the valves. Everything else in it looks and feels good, even the bearings.

RE: 2 Stroke V. 4 Stroke
 

Soooo, it's all personal opinion if Magnums are any good or not? Well, I do like my O.S. and Saito. YS is a bit pricey for me as well, but I heard a lot of good stuff about them. A few guys at my old club had Magnums, and they said that their engines were NOT as good as their O.S. and Saito.

When I got my first Super Tigre .51ts last Spring, I read great things here in RCU about them. Well, maybe the earlier Super Tigre was good, but the newer ones are a hit or a miss in the carb department. Mine was a miss. When I replaced the stock carb with the Perry, and changed the stock muffler over to a Mack. My Supre Tigre is just as good as some of my O.S. engines.

But if I had just went out and just bought a O.S. 61FX or equivalent- I would have payed less than I did when I bought the Super Tigre, muffler and carb all together. I guess sometimes we just have to go out there and find out ourselves to know what is good and not.


Pete