How Good Are the Magnum XL 52 4-Strokes?
01-14-2010, 10:21 AM
#27
Thread Starter
RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: MOTORMAN37
I don't think the little .52 quite be enough.
I use to have a Magnum .61 (no longer available in the US bored out .52) with one head shim removed (had 2) that turned a APC 13-4 @ 10,500 on WC20/20.
I don't think the little .52 quite be enough.
I use to have a Magnum .61 (no longer available in the US bored out .52) with one head shim removed (had 2) that turned a APC 13-4 @ 10,500 on WC20/20.
01-14-2010, 02:05 PM
#28
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: Flyin Beagle
Would this motor be comaparable in power to a 46FX. I am looking at it for my CMPro Lancair which reportedly will come in around 6 to 6.5 lbs???
Would this motor be comaparable in power to a 46FX. I am looking at it for my CMPro Lancair which reportedly will come in around 6 to 6.5 lbs???
No. It would be equal to a good .32 to .36 two-stroke.
Every few years, a bunch of newbies come through that insist on believing fairty tales, such as parity in power between equal displacement two and four-stroke glow engines. Ain't possible, folks. Not if both two and four-stroke examples are not supercharged and both are running the same amount of nitro @ 15% or less.
This is not to say that you or other people would not be happy with how their models flew when powered by a four-stroke glow engine with a displacement equal to the highest recommended two-stroke displacement. Power is a subjective topic and can vary from one individual to another. But let's get real and not try to say that both types of engines produce the same amount of power when at the same displacement. No. No one said they were, but that is what is being implied under the text we are seeing.
Ed Cregger
01-14-2010, 03:22 PM
#29
RE: How Good Are the Magnum XL 52 4-Strokes?
The old rule of thumb is that you mulitply the two stroke size by 1.5 to get the same power four stroke size. So a .52 is about a .35. However the newer four strokes are more powerfull so the rule is no longer acurate but still used. So a .46 two stroke is about a .70 four stroke.
01-14-2010, 03:30 PM
#30
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: Sport_Pilot
The old rule of thumb is that you mulitply the two stroke size by 1.5 to get the same power four stroke size. So a .52 is about a .35. However the newer four strokes are more powerfull so the rule is no longer acurate but still used. So a .46 two stroke is about a .70 four stroke.
The old rule of thumb is that you mulitply the two stroke size by 1.5 to get the same power four stroke size. So a .52 is about a .35. However the newer four strokes are more powerfull so the rule is no longer acurate but still used. So a .46 two stroke is about a .70 four stroke.
I agree that the four-strokes are getting stronger, but so are the two-strokes.
That's the problem with rules of thumb. They aren't that accurate in the first place and then they are subject to change all the while, depending upon ones flying style, expectations and the state of the art.
Ed Cregger
01-14-2010, 03:41 PM
#31
Thread Starter
RE: How Good Are the Magnum XL 52 4-Strokes?
A YS-110 isn't your "average" four stroke either. Those things are beasts!
I'm after thrust and if a prop at a given RPM won't give me what I need, I need to go bigger and this Magnum .52 doesn't compute. I bet it would work great on something like an Great Planes Escapade for sport flying.
I'm after thrust and if a prop at a given RPM won't give me what I need, I need to go bigger and this Magnum .52 doesn't compute. I bet it would work great on something like an Great Planes Escapade for sport flying.
01-14-2010, 03:51 PM
#32
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: SpinnerRow
A YS-110 isn't your ''average'' four stroke either. Those things are beasts!
I'm after thrust and if a prop at a given RPM won't give me what I need, I need to go bigger and this Magnum .52 doesn't compute. I bet it would work great on something like an Great Planes Escapade for sport flying.
A YS-110 isn't your ''average'' four stroke either. Those things are beasts!
I'm after thrust and if a prop at a given RPM won't give me what I need, I need to go bigger and this Magnum .52 doesn't compute. I bet it would work great on something like an Great Planes Escapade for sport flying.
I usually exclude supercharged engines, whether two-stroke (via tuned pipe/expansion chamber), or four-stroke (via crankcase supercharging). You are right. The YS four-strokes are, indeed, beasts.
Ed Cregger
01-14-2010, 08:25 PM
#33
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RE: How Good Are the Magnum XL 52 4-Strokes?
A recent article Iread flew the Magnum 52 FS in Kyosho P-40 and found it adequate. Ibelieve the Kyosho is a .46 size plane. All depends on if you want all out overpowered 3D performance or not.
As my friend Joe is fond of reminding me you do not need a 1 to 1 power to weight ratio to just fly, use the wings.
As my friend Joe is fond of reminding me you do not need a 1 to 1 power to weight ratio to just fly, use the wings.
01-14-2010, 11:39 PM
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RE: How Good Are the Magnum XL 52 4-Strokes?
would you rank the .46 la in the same catagory as the magnum .52? if so thats all the power i need
also the plane im building (wing done) came out to a 52 in wingspan. worse case senario i put it on my 6lb gp rapture that i fly in circles/ mild aerobatics
also the plane im building (wing done) came out to a 52 in wingspan. worse case senario i put it on my 6lb gp rapture that i fly in circles/ mild aerobatics
01-15-2010, 08:38 AM
#35
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: jimmyjames213
would you rank the .46 la in the same catagory as the magnum .52? if so thats all the power i need
also the plane im building (wing done) came out to a 52 in wingspan. worse case senario i put it on my 6lb gp rapture that i fly in circles/ mild aerobatics
would you rank the .46 la in the same catagory as the magnum .52? if so thats all the power i need
also the plane im building (wing done) came out to a 52 in wingspan. worse case senario i put it on my 6lb gp rapture that i fly in circles/ mild aerobatics
01-15-2010, 09:12 AM
#36
RE: How Good Are the Magnum XL 52 4-Strokes?
I 've flown my Magnum .52 4s on several airframes, LT.40. 4Star .40, CG clipped wing cub, SlowPoke and a Twist .40 . It flew all this plane well . I like the 4 stroke torque for pulling these types of planes around. Great fuel economy and worked well with 11x7 12x5/6 and 13x4 wide props.
Power seem to come on at about 1.5.gallon of fuel. Also runs very clean, even using Omega 15% . Idles down so low ,that you can just about count the prop turns. lol It's been a good little engine for me andis getting ready to pull a new Lt.40 kit around.
Power seem to come on at about 1.5.gallon of fuel. Also runs very clean, even using Omega 15% . Idles down so low ,that you can just about count the prop turns. lol It's been a good little engine for me andis getting ready to pull a new Lt.40 kit around.
01-15-2010, 04:05 PM
#37
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: jeffie8696
A recent article I read flew the Magnum 52 FS in Kyosho P-40 and found it adequate. I believe the Kyosho is a .46 size plane. All depends on if you want all out overpowered 3D performance or not.
As my friend Joe is fond of reminding me you do not need a 1 to 1 power to weight ratio to just fly, use the wings.
A recent article I read flew the Magnum 52 FS in Kyosho P-40 and found it adequate. I believe the Kyosho is a .46 size plane. All depends on if you want all out overpowered 3D performance or not.
As my friend Joe is fond of reminding me you do not need a 1 to 1 power to weight ratio to just fly, use the wings.
That, with different words, is what I was trying to point out in one of my posts, Jeffie.
If you are the kind of pilot that installs the largest recommended two-stroke in your models, but end up flying the whole flight at half throttle, then an equally sized four-stroke just might be a better match for your plane. You will need increased takeoff distance to get airborne, but in most situations, that really isn't a problem.
Ed Cregger
01-15-2010, 04:10 PM
#38
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RE: How Good Are the Magnum XL 52 4-Strokes?
Improving how it runs after a gallon and a half of fuel is pretty much true for many of the Asian produced ringed engines.
Nice color combo on your purple trim and yellow model.
Like I said earlier, it all depends upon what you think is adequate power. If you fly .46 to .52 two-strokes at half throttle most times, then flying 3/4 to full throttle with a .52 four-stroke may just be your cup of tea. But they still do not produce the same amount of power. <G>
Ed Cregger
Nice color combo on your purple trim and yellow model.
Like I said earlier, it all depends upon what you think is adequate power. If you fly .46 to .52 two-strokes at half throttle most times, then flying 3/4 to full throttle with a .52 four-stroke may just be your cup of tea. But they still do not produce the same amount of power. <G>
Ed Cregger
01-16-2010, 09:48 AM
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RE: How Good Are the Magnum XL 52 4-Strokes?
...79,90$ is quite reasonable for the little Magnum. I bought the 61FS for around £100 once.
These Sanye engines are not as trouble free as O.S. engines. I bought the Sanye 180FS recently. As it came out of the box there was no valve clearance at all. Fortunately, I checked valve clearance before I tried to run the engine. My 61FS lost parts of the carburator in flight. The newer 180FS has a differenty designed carburator without this paper washer under the screw that keeps the carb together. Looks like Sanye improved the design. That is great.
In opposite to some other chaps I think O.S. is worth the higher price. Especially the new Alpha series is a far advanced typ of engine. Sanye just gave its Magnum brand a blue head. And if you think about all these shop discounts buying an O.S. engines, the price reduction for the Magums is more than justified.
Even after 1 gal. of fuel my 61FS never came close to my O.S. 56a. But apart from performance the cheaper Chinese engine started easily and never quite in the air until the carb came apart (I check all screws from time to time).
Another interesting story is the O.S. 30FS against the Sanye/Magnum 30FS. Again, the O.S. has more performance. My buddy and I each got the Hyperion Hayate 25e. He used the Sanye (Magnum) 30FS and I the O.S. 30. The O.S. turned the APC10x6 with autority, the Magnum couldn´t. In ther air the Magnum propelled Hayate was only prey for my O.S. powered plane. Interesting here, with the same running time, the small Magnum needed to get the valve clearance readjusted from time to time, the O.S. needn´t.
Thus, if you like to get a couple of 40 size models in your hanger and you look for something different to an O.S. 56a or Saito 56/62a, the small 52FS could be your choice. But if you look for only one engine in that size range I would rather buy an O.S., Saito or even YS.
These Sanye engines are not as trouble free as O.S. engines. I bought the Sanye 180FS recently. As it came out of the box there was no valve clearance at all. Fortunately, I checked valve clearance before I tried to run the engine. My 61FS lost parts of the carburator in flight. The newer 180FS has a differenty designed carburator without this paper washer under the screw that keeps the carb together. Looks like Sanye improved the design. That is great.
In opposite to some other chaps I think O.S. is worth the higher price. Especially the new Alpha series is a far advanced typ of engine. Sanye just gave its Magnum brand a blue head. And if you think about all these shop discounts buying an O.S. engines, the price reduction for the Magums is more than justified.
Even after 1 gal. of fuel my 61FS never came close to my O.S. 56a. But apart from performance the cheaper Chinese engine started easily and never quite in the air until the carb came apart (I check all screws from time to time).
Another interesting story is the O.S. 30FS against the Sanye/Magnum 30FS. Again, the O.S. has more performance. My buddy and I each got the Hyperion Hayate 25e. He used the Sanye (Magnum) 30FS and I the O.S. 30. The O.S. turned the APC10x6 with autority, the Magnum couldn´t. In ther air the Magnum propelled Hayate was only prey for my O.S. powered plane. Interesting here, with the same running time, the small Magnum needed to get the valve clearance readjusted from time to time, the O.S. needn´t.
Thus, if you like to get a couple of 40 size models in your hanger and you look for something different to an O.S. 56a or Saito 56/62a, the small 52FS could be your choice. But if you look for only one engine in that size range I would rather buy an O.S., Saito or even YS.
01-17-2010, 12:40 AM
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RE: How Good Are the Magnum XL 52 4-Strokes?
i just got a magnum .52fs at a swap meet (nib) for $85 w/ plug. its turning a mas 11x7 around 10000 rpm (dont want to peak it) on 0% nitro fuel. its idleing really bad (idles at half throttle) but its because its way to rich. ill mess with it more tomorrow but the compression is getting better with only 16oz worth of fuel. it seems to be comparable to a .46 la (i had a .46la on the same plane as the one i put the .52 on)
08-09-2010, 08:58 PM
#43
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: jrotor
Hi all
Do you know if 52RFS can turn 14x4 prop at around 8500 RPM ?
Hi all
Do you know if 52RFS can turn 14x4 prop at around 8500 RPM ?
Nope. You need an .82 or larger to get into that territory. The standard prop for the .52 is a 12x6, so I imagine that a 13x4 would be about tops and even that might take more nitro than I like to burn (5% to 10%).
Ed Cregger
08-09-2010, 10:09 PM
#44
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: jeffie8696
Top Flite wood 12X6 ran 9100 rpm from my Mag52FS according to the Pe Rievers spreadsheet that is equivalent to 5.5 lbs thrust and 45 mph. Just raw data to do with what you please.
Top Flite wood 12X6 ran 9100 rpm from my Mag52FS according to the Pe Rievers spreadsheet that is equivalent to 5.5 lbs thrust and 45 mph. Just raw data to do with what you please.
Thanks for the data.
If you haven't flown a Florio Stunt Wagon, you should. A simple build with 750 square inches of wing area. The ailerons have a 4" chord (believe me, you'll need it). This model is a ball to fly as a sport plane. I've flown mine with glow and dieselized OS .32F-H, a K&B .28 and I was going to put a .52 four-stroke on the nose, but sold it when I was made an offer I couldn't refuse.
I have the plans and some templates and I'm about to make some more. One of my favorite modes of flying with this model is to use only throttle, rudder and elevator. The flaperon function is engaged and the ailerons are drooped about ten degrees. Then I takeoff, trim the rudder and elevator and after that I shoot touch and goes using just the throttle and a teensy bit of rudder here and there. Why? Because it is fun.
The one thing that you don't want to do is to fly the model at full throttle unless you are going straight up or in a steep, high-G bank. Doing so will shred the model in no time.
Ed, NM2K
08-09-2010, 10:24 PM
#45
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: jimmyjames213
i just got a magnum .52fs at a swap meet (nib) for $85 w/ plug. its turning a mas 11x7 around 10000 rpm (dont want to peak it) on 0% nitro fuel. its idleing really bad (idles at half throttle) but its because its way to rich. ill mess with it more tomorrow but the compression is getting better with only 16oz worth of fuel. it seems to be comparable to a .46 la (i had a .46la on the same plane as the one i put the .52 on)
i just got a magnum .52fs at a swap meet (nib) for $85 w/ plug. its turning a mas 11x7 around 10000 rpm (dont want to peak it) on 0% nitro fuel. its idleing really bad (idles at half throttle) but its because its way to rich. ill mess with it more tomorrow but the compression is getting better with only 16oz worth of fuel. it seems to be comparable to a .46 la (i had a .46la on the same plane as the one i put the .52 on)
If your engine idles at half throttle - it is broke! Send it back and get it fixed.
I suspect that the OS .40-.46 LA provides pretty much the same performance as the Magnum .52 four-stroke. The Magnum will sound better.
Ed Cregger
08-09-2010, 10:29 PM
#46
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: Pippin
...79,90$ is quite reasonable for the little Magnum. I bought the 61FS for around £100 once.
These Sanye engines are not as trouble free as O.S. engines. I bought the Sanye 180FS recently. As it came out of the box there was no valve clearance at all. Fortunately, I checked valve clearance before I tried to run the engine. My 61FS lost parts of the carburator in flight. The newer 180FS has a differenty designed carburator without this paper washer under the screw that keeps the carb together. Looks like Sanye improved the design. That is great.
In opposite to some other chaps I think O.S. is worth the higher price. Especially the new Alpha series is a far advanced typ of engine. Sanye just gave its Magnum brand a blue head. And if you think about all these shop discounts buying an O.S. engines, the price reduction for the Magums is more than justified.
Even after 1 gal. of fuel my 61FS never came close to my O.S. 56a. But apart from performance the cheaper Chinese engine started easily and never quite in the air until the carb came apart (I check all screws from time to time).
Another interesting story is the O.S. 30FS against the Sanye/Magnum 30FS. Again, the O.S. has more performance. My buddy and I each got the Hyperion Hayate 25e. He used the Sanye (Magnum) 30FS and I the O.S. 30. The O.S. turned the APC10x6 with autority, the Magnum couldn´t. In ther air the Magnum propelled Hayate was only prey for my O.S. powered plane. Interesting here, with the same running time, the small Magnum needed to get the valve clearance readjusted from time to time, the O.S. needn´t.
Thus, if you like to get a couple of 40 size models in your hanger and you look for something different to an O.S. 56a or Saito 56/62a, the small 52FS could be your choice. But if you look for only one engine in that size range I would rather buy an O.S., Saito or even YS.
...79,90$ is quite reasonable for the little Magnum. I bought the 61FS for around £100 once.
These Sanye engines are not as trouble free as O.S. engines. I bought the Sanye 180FS recently. As it came out of the box there was no valve clearance at all. Fortunately, I checked valve clearance before I tried to run the engine. My 61FS lost parts of the carburator in flight. The newer 180FS has a differenty designed carburator without this paper washer under the screw that keeps the carb together. Looks like Sanye improved the design. That is great.
In opposite to some other chaps I think O.S. is worth the higher price. Especially the new Alpha series is a far advanced typ of engine. Sanye just gave its Magnum brand a blue head. And if you think about all these shop discounts buying an O.S. engines, the price reduction for the Magums is more than justified.
Even after 1 gal. of fuel my 61FS never came close to my O.S. 56a. But apart from performance the cheaper Chinese engine started easily and never quite in the air until the carb came apart (I check all screws from time to time).
Another interesting story is the O.S. 30FS against the Sanye/Magnum 30FS. Again, the O.S. has more performance. My buddy and I each got the Hyperion Hayate 25e. He used the Sanye (Magnum) 30FS and I the O.S. 30. The O.S. turned the APC10x6 with autority, the Magnum couldn´t. In ther air the Magnum propelled Hayate was only prey for my O.S. powered plane. Interesting here, with the same running time, the small Magnum needed to get the valve clearance readjusted from time to time, the O.S. needn´t.
Thus, if you like to get a couple of 40 size models in your hanger and you look for something different to an O.S. 56a or Saito 56/62a, the small 52FS could be your choice. But if you look for only one engine in that size range I would rather buy an O.S., Saito or even YS.
I like, buy and use OS engines too. No, I do not think that the exhorbitant prices of the latest OS four-strokes are justified. Just like I don't think that OS' in the USA price of $2,000 to $2,500 for the same engine (5-cylinder radial) that was selling at $1,400 dollars and change a few days before are worth it. The Tower folks have lost their minds.
I have plenty of high quality Enya, Saito, older OS & YS engines. They can keep their over priced late edition OS engines. I refuse to be gouged in such a manner.
Ed, NM2K
08-09-2010, 10:34 PM
#47
RE: How Good Are the Magnum XL 52 4-Strokes?
I've never seen any of the new style OS four strokes at the field. I'm sure that they are good engines but due to the prices that Tower tries to get for them, I've never seen one.
Havn't seen any Fasst radios either as everyone has Spektrum or JR
Havn't seen any Fasst radios either as everyone has Spektrum or JR
08-09-2010, 10:55 PM
#48
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: w8ye
I've never seen any of the new style OS four strokes at the field. I'm sure that they are good engines but due to the prices that Tower tries to get for them, I've never seen one.
Havn't seen any Fasst radios either as everyone has Spektrum or JR
I've never seen any of the new style OS four strokes at the field. I'm sure that they are good engines but due to the prices that Tower tries to get for them, I've never seen one.
Havn't seen any Fasst radios either as everyone has Spektrum or JR
From what I have heard about the latest OS four-strokes, they do offer a bit more power than the previous version(s).
I have JR, Spektrum and Futaba FASST systems.
I've flown my JR systems on 50 MHz, 53 MHz and 72 MHz with no problems. I have a third party JR Tx module and Rx (three letters, starts with a G) on 2.4 GHz, but I haven't used it yet. I have a 6-channel Park Flyer Spektrum and a 7-channel Spektrum. I have yet to fly them.
From what I have read about the third party 2.4 GHz modules for the JR, I'm hesitant to send them airborne.
Ed, NM2K
08-10-2010, 02:56 PM
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: NM2K
If your engine idles at half throttle - it is broke! Send it back and get it fixed.
I suspect that the OS .40-.46 LA provides pretty much the same performance as the Magnum .52 four-stroke. The Magnum will sound better.
Ed Cregger
ORIGINAL: jimmyjames213
i just got a magnum .52fs at a swap meet (nib) for $85 w/ plug. its turning a mas 11x7 around 10000 rpm (dont want to peak it) on 0% nitro fuel. its idleing really bad (idles at half throttle) but its because its way to rich. ill mess with it more tomorrow but the compression is getting better with only 16oz worth of fuel. it seems to be comparable to a .46 la (i had a .46la on the same plane as the one i put the .52 on)
i just got a magnum .52fs at a swap meet (nib) for $85 w/ plug. its turning a mas 11x7 around 10000 rpm (dont want to peak it) on 0% nitro fuel. its idleing really bad (idles at half throttle) but its because its way to rich. ill mess with it more tomorrow but the compression is getting better with only 16oz worth of fuel. it seems to be comparable to a .46 la (i had a .46la on the same plane as the one i put the .52 on)
If your engine idles at half throttle - it is broke! Send it back and get it fixed.
I suspect that the OS .40-.46 LA provides pretty much the same performance as the Magnum .52 four-stroke. The Magnum will sound better.
Ed Cregger
well ill guess i will give an update on my magnum .52 rfs
it idles around 2500 on 5% nitro no problem, im actually surprised at how well it pulls around my 6+ lb gp rapture, you cant tell the difference between the 4 stroke (11x7 prop) and a .46 2 stroke w/ a 11x5 both fly the same speed (in normal flight they feel the same), its only when you go vertical can you tell a difference, the 4 stroke dies out after 100 feet while the 2 stroke has unlimited. the 4 stroke will keep pulling it at a 45 degree angle with no problem, loop it just fine, rolling circles it starts to loose power but its not terrible.
if your just putting around the sky in circles, doing basic loops, spins, rolls, ect the magnum .52 will work fine in your .40 sized plane.
08-10-2010, 09:50 PM
#50
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RE: How Good Are the Magnum XL 52 4-Strokes?
ORIGINAL: jimmyjames213
thats cause its was 10 degrees out, running a crap plug, and 0% nitro
well ill guess i will give an update on my magnum .52 rfs
it idles around 2500 on 5% nitro no problem, im actually surprised at how well it pulls around my 6+ lb gp rapture, you cant tell the difference between the 4 stroke (11x7 prop) and a .46 2 stroke w/ a 11x5 both fly the same speed (in normal flight they feel the same), its only when you go vertical can you tell a difference, the 4 stroke dies out after 100 feet while the 2 stroke has unlimited. the 4 stroke will keep pulling it at a 45 degree angle with no problem, loop it just fine, rolling circles it starts to loose power but its not terrible.
if your just putting around the sky in circles, doing basic loops, spins, rolls, ect the magnum .52 will work fine in your .40 sized plane.
ORIGINAL: NM2K
If your engine idles at half throttle - it is broke! Send it back and get it fixed.
I suspect that the OS .40-.46 LA provides pretty much the same performance as the Magnum .52 four-stroke. The Magnum will sound better.
Ed Cregger
ORIGINAL: jimmyjames213
i just got a magnum .52fs at a swap meet (nib) for $85 w/ plug. its turning a mas 11x7 around 10000 rpm (dont want to peak it) on 0% nitro fuel. its idleing really bad (idles at half throttle) but its because its way to rich. ill mess with it more tomorrow but the compression is getting better with only 16oz worth of fuel. it seems to be comparable to a .46 la (i had a .46la on the same plane as the one i put the .52 on)
i just got a magnum .52fs at a swap meet (nib) for $85 w/ plug. its turning a mas 11x7 around 10000 rpm (dont want to peak it) on 0% nitro fuel. its idleing really bad (idles at half throttle) but its because its way to rich. ill mess with it more tomorrow but the compression is getting better with only 16oz worth of fuel. it seems to be comparable to a .46 la (i had a .46la on the same plane as the one i put the .52 on)
If your engine idles at half throttle - it is broke! Send it back and get it fixed.
I suspect that the OS .40-.46 LA provides pretty much the same performance as the Magnum .52 four-stroke. The Magnum will sound better.
Ed Cregger
well ill guess i will give an update on my magnum .52 rfs
it idles around 2500 on 5% nitro no problem, im actually surprised at how well it pulls around my 6+ lb gp rapture, you cant tell the difference between the 4 stroke (11x7 prop) and a .46 2 stroke w/ a 11x5 both fly the same speed (in normal flight they feel the same), its only when you go vertical can you tell a difference, the 4 stroke dies out after 100 feet while the 2 stroke has unlimited. the 4 stroke will keep pulling it at a 45 degree angle with no problem, loop it just fine, rolling circles it starts to loose power but its not terrible.
if your just putting around the sky in circles, doing basic loops, spins, rolls, ect the magnum .52 will work fine in your .40 sized plane.
Ah-ha! Well that explains it.
I'll bet that a 12x5 or 6 would improve your four-stroke's vertical performance without losing its top speed.
I've always found the 11x7 prop size to be something magical for mid sized engines. It always performed better than I thought it would on .40 thru .55 sized two-stroke engines equipped with mufflers. Just an observation. No, I haven't scientifically quantified this hunch. Just a feeling.
Ed Cregger