JBA .56
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RE: JBA .56
I'm just happy that, even if I can't be flying right now, at least one of my engines is getting some stick time!
I wonder if I can talk my wife into letting me run some engines in the living room? [X(]
I wonder if I can talk my wife into letting me run some engines in the living room? [X(]
#27
RE: JBA .56
Hi BigMustafa,your wish is not so hard to do as you can think.Only you will need a separate room to open window for a long time in winterdays.I did this several times and I think you can too. Mount your engine firmly on a bench and take your bench to that room.Put a garden hose suitable to exhaust outlet and put other end into a about 5 liters pet bottle or similiar container,quarter full of water. (garden hose will go thru the tight fit hole on tap).Open some discharge holes upper end of the bottle to let exhaust gas go. Open the window,Now ready to run.Good luck.(Oil will be kept by water and bottle and only exhaust gasses will be discharge thru holes of upper end.
#28
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RE: JBA .56
Turk1-Bigedmustafa's engine is down here in Florida for testing. He ordered it and had it sent to me so he actually hasn't ever seen it.
Here's my prop testing results for the JBA .56:
Bare Engine Weight: 13.1
Muffler Weight: 5.3
Total flying Weight: 18.4 oz.
Temp: Low to middle 60s
Humidity: High
Fuel: Omega 10% nitro, castor blend
Plug: K&B regular (non-idle bar)
Tach: Tower cheapie
Prop Muffler Jett tuned muffler
11-6APC 12,800 13,800
11-6MA 13,100 13,800
11-7APC 12,400 12,600
11-8RevUp 11,300
12-6MA 11,600 12,000
12-7Zinger 10,200
12-7APC 10,800
12.25-3.75 13,000 13,900
Here's what I previously got on my OS .55AX
11-6 12,800 14,500
11-7 12,200 13,700
12.25-3.75 14,500 (no muffled rpm)
Actually, the JBA .56 looks really good for the price, especially with a muffler. I would say an 11-7 or 12-6 would be a good sport prop. Use the 12.25-3.75 for 3D and fun fly stuff. That's what I run on the OS 55 and plan to use on my JBA .56, which just came in.
Here are some readings I took several years ago when I bought my first OS .46AX. They were published here on RCU if you search far enough back. They were only on the APC 12.25-3.75 3D prop. The fuel, temperature and humidity were the same as above.
OS .46AX 12,500
OS .46FX (old engine) 11,400
TT .46Pro (old engine) 11,500
Magnum .52XLS 12,800
The JBA .56 turns higher than any of these engines. The TT .46Pro will probably be better on a small prop (10-6 or 9-7) but probably wouldn't turn the larger props nearly as well, 11-7 or 12-6.
The JBA .56 seems to be more conservatively ported and timed compared to the OS .55. It doesn't respond to the Jett-Stream tuned muffler as well. You nominally need about 13,500 for the Jett to work. You can see that the props, 11-6APC & 12.25-3.75, that were close to 13,000 got a pretty large boost. Bottom line on the tuned muffler is I don't think the Jett is worth it for the JBA. With the OS, I gained 1700 on the 11-6 and 1500 on the 11-7 and that is a significant boost.
Bottom line on the engine: I'll have to fly it to see how it runs in the air, but from my initial testing and using the stock muffler, it is roughly the equivalent of the OS .55AX for a lot less money.
It's quite a nice handling engine. Never did bite me when hand flipping. This also indicates a milder timing that a racier type engine.
Here's my prop testing results for the JBA .56:
Bare Engine Weight: 13.1
Muffler Weight: 5.3
Total flying Weight: 18.4 oz.
Temp: Low to middle 60s
Humidity: High
Fuel: Omega 10% nitro, castor blend
Plug: K&B regular (non-idle bar)
Tach: Tower cheapie
Prop Muffler Jett tuned muffler
11-6APC 12,800 13,800
11-6MA 13,100 13,800
11-7APC 12,400 12,600
11-8RevUp 11,300
12-6MA 11,600 12,000
12-7Zinger 10,200
12-7APC 10,800
12.25-3.75 13,000 13,900
Here's what I previously got on my OS .55AX
11-6 12,800 14,500
11-7 12,200 13,700
12.25-3.75 14,500 (no muffled rpm)
Actually, the JBA .56 looks really good for the price, especially with a muffler. I would say an 11-7 or 12-6 would be a good sport prop. Use the 12.25-3.75 for 3D and fun fly stuff. That's what I run on the OS 55 and plan to use on my JBA .56, which just came in.
Here are some readings I took several years ago when I bought my first OS .46AX. They were published here on RCU if you search far enough back. They were only on the APC 12.25-3.75 3D prop. The fuel, temperature and humidity were the same as above.
OS .46AX 12,500
OS .46FX (old engine) 11,400
TT .46Pro (old engine) 11,500
Magnum .52XLS 12,800
The JBA .56 turns higher than any of these engines. The TT .46Pro will probably be better on a small prop (10-6 or 9-7) but probably wouldn't turn the larger props nearly as well, 11-7 or 12-6.
The JBA .56 seems to be more conservatively ported and timed compared to the OS .55. It doesn't respond to the Jett-Stream tuned muffler as well. You nominally need about 13,500 for the Jett to work. You can see that the props, 11-6APC & 12.25-3.75, that were close to 13,000 got a pretty large boost. Bottom line on the tuned muffler is I don't think the Jett is worth it for the JBA. With the OS, I gained 1700 on the 11-6 and 1500 on the 11-7 and that is a significant boost.
Bottom line on the engine: I'll have to fly it to see how it runs in the air, but from my initial testing and using the stock muffler, it is roughly the equivalent of the OS .55AX for a lot less money.
It's quite a nice handling engine. Never did bite me when hand flipping. This also indicates a milder timing that a racier type engine.
#31
RE: JBA .56
Ed, you followed through with that report quickly!
Have you compared the weight of the 56 with your (after Christmas.... either of?) OS 55's? Interesting that they seem to put out the same power.
Thanks,
Ernie
Have you compared the weight of the 56 with your (after Christmas.... either of?) OS 55's? Interesting that they seem to put out the same power.
Thanks,
Ernie
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RE: JBA .56
ORIGINAL: Turk1
Hi BigMustafa,your wish is not so hard to do as you can think.Only you will need a separate room to open window for a long time in winterdays.I did this several times and I think you can too. Mount your engine firmly on a bench and take your bench to that room.Put a garden hose suitable to exhaust outlet and put other end into a about 5 liters pet bottle or similiar container,quarter full of water. (garden hose will go thru the tight fit hole on tap).Open some discharge holes upper end of the bottle to let exhaust gas go. Open the window,Now ready to run.Good luck.(Oil will be kept by water and bottle and only exhaust gasses will be discharge thru holes of upper end.
Hi BigMustafa,your wish is not so hard to do as you can think.Only you will need a separate room to open window for a long time in winterdays.I did this several times and I think you can too. Mount your engine firmly on a bench and take your bench to that room.Put a garden hose suitable to exhaust outlet and put other end into a about 5 liters pet bottle or similiar container,quarter full of water. (garden hose will go thru the tight fit hole on tap).Open some discharge holes upper end of the bottle to let exhaust gas go. Open the window,Now ready to run.Good luck.(Oil will be kept by water and bottle and only exhaust gasses will be discharge thru holes of upper end.
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RE: JBA .56
ORIGINAL: Ernie Misner
Ed, you followed through with that report quickly!
Have you compared the weight of the 56 with your (after Christmas.... either of?) OS 55's? Interesting that they seem to put out the same power.
Thanks,
Ernie
Ed, you followed through with that report quickly!
Have you compared the weight of the 56 with your (after Christmas.... either of?) OS 55's? Interesting that they seem to put out the same power.
Thanks,
Ernie
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RE: JBA .56
ORIGINAL: Ed_Moorman
Prop Muffler Jett tuned muffler
12.25-3.75 13,000 13,900
Here's what I previously got on my OS .55AX
12.25-3.75 14,500 (no muffled rpm)
it is roughly the equivalent of the OS .55AX for a lot less money.
Prop Muffler Jett tuned muffler
12.25-3.75 13,000 13,900
Here's what I previously got on my OS .55AX
12.25-3.75 14,500 (no muffled rpm)
it is roughly the equivalent of the OS .55AX for a lot less money.
What I *would* be interested in is the throttling characteristics. How does it respond after being held at 1/3 throttle for 20 seconds then transitioned quickly to full. That's where so many otherwise good engines just can't hold a candle to OS/TT and other more expensive engines.
While the OS, TT etc will snap to full RPMs immediately, far too many of the cheaper alternatives will stumble either a little or a lot. That can be the difference between having fun with your 3D plane and looking for a bag to hold all the bits :-)
#35
RE: JBA .56
ORIGINAL: Ed_Moorman
I just ran the break-in on BigEd's JBA .56. Seems to run like an SK, which is really good.
1-flip started on every tank full. Never had to resort to a starter.
After five 8-ounce tanks, I am turning an APC 11-6 at 12,800. This is the same as my OS .55AX. Same prop actually and same fuel, Omega 10% nitro, castor blend fuel.
I set the low end on the 5th tank and it will hold a low idle (I didn't check the actual rpm, but it's low enough for me to taxi) then go straight to full power without a hesitation. I also ran for more than 30 seconds with the carb half open, then full power. No hesitation again. Next, I ran at 1/4 open for 30-40 secs and full power. It seems to have a very good carb.
It does not shut down when you close the carb. Those of us who have SKs know that it takes about a gallon of fuel for the engine to really come in and at around that time, it'll shut down. This was mentioned in the SK thread and it worked for my engines. Maybe it takes that long for the castor oil crud to close up all the minor air leaks. I don't know. I do know the SKs keep gaining power for a gallon or so. I am going to assume the same for the JBA.
I haven't flown it yet to see how it reacts in the air, but at first glance, it seems to be a good running power house for a low price, $80.
I do plan to run several other sizes of 11" and 12" props and I have a Jett muffler to try. Since Ed can't use it right now up in Omaha due to snow and cold, I'm going to give it a good test. By the way, I also ordered my own JBA .56.
I just ran the break-in on BigEd's JBA .56. Seems to run like an SK, which is really good.
1-flip started on every tank full. Never had to resort to a starter.
After five 8-ounce tanks, I am turning an APC 11-6 at 12,800. This is the same as my OS .55AX. Same prop actually and same fuel, Omega 10% nitro, castor blend fuel.
I set the low end on the 5th tank and it will hold a low idle (I didn't check the actual rpm, but it's low enough for me to taxi) then go straight to full power without a hesitation. I also ran for more than 30 seconds with the carb half open, then full power. No hesitation again. Next, I ran at 1/4 open for 30-40 secs and full power. It seems to have a very good carb.
It does not shut down when you close the carb. Those of us who have SKs know that it takes about a gallon of fuel for the engine to really come in and at around that time, it'll shut down. This was mentioned in the SK thread and it worked for my engines. Maybe it takes that long for the castor oil crud to close up all the minor air leaks. I don't know. I do know the SKs keep gaining power for a gallon or so. I am going to assume the same for the JBA.
I haven't flown it yet to see how it reacts in the air, but at first glance, it seems to be a good running power house for a low price, $80.
I do plan to run several other sizes of 11" and 12" props and I have a Jett muffler to try. Since Ed can't use it right now up in Omaha due to snow and cold, I'm going to give it a good test. By the way, I also ordered my own JBA .56.
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RE: JBA .56
ORIGINAL: Turk1
Hi XJet I think you missed that part.
Hi XJet I think you missed that part.
#37
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RE: JBA .56
The rpm on the 12.25x3.75 was with the Jett tuned muffler. For some reason (I was probably too lazy) I didn't take muffled rpms on 12" props on the 55AX.
I also noted that the JBA seemed to not respond to the tuned muffler as well as the OS, milder timing, in my opinion. On the two 11" props, 11-6 APC & 11-7 APC, the JBA, with the stock muffler, was equal to or a couple hundred rpm beter than the OS.
I have a second OS .55AX new in the box and also my own JBA .56, so I'll do a second, but shorter test on those two.
The JBA .56 weighs, using my digital scale, 18.4 ounces. As I recall, the OS weighed 18.3. Both of these are with muffler. The interesting thing is the JBA muffler weighs a ton, coming in at 5.3 ounces. This is even heavier than a Jett tuned muffler. The bare engine weighed separately is 13.1 ounces.
I did run the JBA on the bench at 1/2 & 1/4 throttle, then hit full power. The engine went up smoothly. That still doesn't tell me what it'll do in the air. I have a Goldberg Wild Stik with an SK 50 on it. I think I'll remove it and mount Ed's engine for a quick flight test. The Wild Stik can't use full power in level flight because of the wide controls (Ail: 4", El: 4", Rud: 6") and the chance of flutter. It's more of a high wing 3D plane like the Heckler I used to fly. It should be a good test for running at partial power.
I also noted that the JBA seemed to not respond to the tuned muffler as well as the OS, milder timing, in my opinion. On the two 11" props, 11-6 APC & 11-7 APC, the JBA, with the stock muffler, was equal to or a couple hundred rpm beter than the OS.
I have a second OS .55AX new in the box and also my own JBA .56, so I'll do a second, but shorter test on those two.
The JBA .56 weighs, using my digital scale, 18.4 ounces. As I recall, the OS weighed 18.3. Both of these are with muffler. The interesting thing is the JBA muffler weighs a ton, coming in at 5.3 ounces. This is even heavier than a Jett tuned muffler. The bare engine weighed separately is 13.1 ounces.
I did run the JBA on the bench at 1/2 & 1/4 throttle, then hit full power. The engine went up smoothly. That still doesn't tell me what it'll do in the air. I have a Goldberg Wild Stik with an SK 50 on it. I think I'll remove it and mount Ed's engine for a quick flight test. The Wild Stik can't use full power in level flight because of the wide controls (Ail: 4", El: 4", Rud: 6") and the chance of flutter. It's more of a high wing 3D plane like the Heckler I used to fly. It should be a good test for running at partial power.
#38
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RE: JBA .56
I got another small bit of anectdotal information from Ed Moorman via e-mail:
I'm anxious to hear about his flying experiences over the next few weeks!
Original: Ed Moorman
One thing I failed to mention, the muffler never did leak at the seams. And it never did rotate. Good fit.
One thing I failed to mention, the muffler never did leak at the seams. And it never did rotate. Good fit.
#39
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RE: JBA .56
Today (New Years Day) I did a little more testing on the JBA .56. I had already tested the Jett-Stream tuned muffler and found it wasn't very helpful on the JBA. I decided to make a quick check with a Tower muffler and the E-3020 from the OS .55AX.
Muffler weights:
JBA: 5.5 oz (This was a different JBA .56 muffler from the one I weighed before and it turned out to be .2 oz heavier)
Tower: 3.8 oz
OS E-3020: 4.2 oz
Notice that the JBA muffler is sort of a slug. When I started weighing Ed's engine and noticed the JBA was really heavy, it gave me the idea to try other mufflers. The JBA is even heavier than a Jett, so it's too bad the Jett didn't work very well.
rpm testing
My Tower mini tach was acting flaky so I used a Thunder Tiger tach. The rpm on the control prop were a few hundred lower than with the Tower tach, but all you reall need is the relative numbers.
Prop 12.25-3.75 APC 3D prop
JBA muffler: 12,700 (This is 300 rpm lower than the original test, but with a different tach)
Tower: 12,300
OS E-3020 12,300
The JBA muffler showed a higher rpm on the first run and I duplicated it again after running the Tower & OS muffler just to make sure. Both times it peaked at 12,700, so I am confident that the JBA muffler on the JBA .56 is faster.
Here's a couple more of my thoughts. I may try the JBA muffler on the OS .55 to see what happens. The other thing is the JBA .56 is really has .579 cu. in. dosplacement, so it's a .58. It may need a 61 sized muffler. It looks in the photo showing the Tower muffler on top and the JBA .56 muffler on the bottom, that the JBA may be slightly larger. The larger size of the forward casting is probably what is adding the extra weight. The second photo shows the JBA on the test stand with the OS and Jett-Stream mufflers.
I did see a thread, maybe a couple of years ago, on some testing of the Tower muffler on an OS .50SZ. He had access to a machine shop and had a longer center section made from thick walled tubing. After he lengthened the center, he noticed an rpm increase.
Muffler weights:
JBA: 5.5 oz (This was a different JBA .56 muffler from the one I weighed before and it turned out to be .2 oz heavier)
Tower: 3.8 oz
OS E-3020: 4.2 oz
Notice that the JBA muffler is sort of a slug. When I started weighing Ed's engine and noticed the JBA was really heavy, it gave me the idea to try other mufflers. The JBA is even heavier than a Jett, so it's too bad the Jett didn't work very well.
rpm testing
My Tower mini tach was acting flaky so I used a Thunder Tiger tach. The rpm on the control prop were a few hundred lower than with the Tower tach, but all you reall need is the relative numbers.
Prop 12.25-3.75 APC 3D prop
JBA muffler: 12,700 (This is 300 rpm lower than the original test, but with a different tach)
Tower: 12,300
OS E-3020 12,300
The JBA muffler showed a higher rpm on the first run and I duplicated it again after running the Tower & OS muffler just to make sure. Both times it peaked at 12,700, so I am confident that the JBA muffler on the JBA .56 is faster.
Here's a couple more of my thoughts. I may try the JBA muffler on the OS .55 to see what happens. The other thing is the JBA .56 is really has .579 cu. in. dosplacement, so it's a .58. It may need a 61 sized muffler. It looks in the photo showing the Tower muffler on top and the JBA .56 muffler on the bottom, that the JBA may be slightly larger. The larger size of the forward casting is probably what is adding the extra weight. The second photo shows the JBA on the test stand with the OS and Jett-Stream mufflers.
I did see a thread, maybe a couple of years ago, on some testing of the Tower muffler on an OS .50SZ. He had access to a machine shop and had a longer center section made from thick walled tubing. After he lengthened the center, he noticed an rpm increase.
#41
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My Feedback: (1)
RE: JBA .56
I haven't seen the JBA P-Box muffler. I'll e-mail and ask about it.
I did get one flight in on a Goldberg Wild Stik with the JBA 56. The engine ran well in the air. No problems, no stopping. I stayed at half power most of the time because of the extremely wide control surfaces on the Wild Stik. There was no loading up at half power.
Vertical on the 5 1/2 lb plane was excellent. I can take off and rotate immediately and keep going on up.
The idle was good and the engine shut down after a slight delay.
I would have flown more, but I've been under the weather with a cold virus that has hit everyone at work and the wife at home. I wasn't feeling like doing anything except one flight to see the JBA fly. Maybe this weekend, if the weather cooperates.
I did get one flight in on a Goldberg Wild Stik with the JBA 56. The engine ran well in the air. No problems, no stopping. I stayed at half power most of the time because of the extremely wide control surfaces on the Wild Stik. There was no loading up at half power.
Vertical on the 5 1/2 lb plane was excellent. I can take off and rotate immediately and keep going on up.
The idle was good and the engine shut down after a slight delay.
I would have flown more, but I've been under the weather with a cold virus that has hit everyone at work and the wife at home. I wasn't feeling like doing anything except one flight to see the JBA fly. Maybe this weekend, if the weather cooperates.
#42
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RE: JBA .56
This new muffler comes with the new 56 F series engine.
I've tested this new engine (pre-series batch) for a spanish local R/C magazine review.
It's more powerful than old style JBA56 AND more powerfull than OS55AX (also reviewed)
Production batch are painted in blue (cranckase and head).
I'm very impressed with the performance and reliability of this engine. It can turn little props at hi rpm. (> 16.000) or a big 14x7 prop at more than 9.000 rpm without overheating.
Almost 14.000 rpm with 11x6MA.
I've tested this new engine (pre-series batch) for a spanish local R/C magazine review.
It's more powerful than old style JBA56 AND more powerfull than OS55AX (also reviewed)
Production batch are painted in blue (cranckase and head).
I'm very impressed with the performance and reliability of this engine. It can turn little props at hi rpm. (> 16.000) or a big 14x7 prop at more than 9.000 rpm without overheating.
Almost 14.000 rpm with 11x6MA.
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RE: JBA .56
ORIGINAL: mpascual
I'm very impressed with the performance and reliability of this engine. It can turn little props at hi rpm. (> 16.000) or a big 14x7 prop at more than 9.000 rpm without overheating.
Almost 14.000 rpm with 11x6MA.
I'm very impressed with the performance and reliability of this engine. It can turn little props at hi rpm. (> 16.000) or a big 14x7 prop at more than 9.000 rpm without overheating.
Almost 14.000 rpm with 11x6MA.
Do you have figures for the APC 12x4 prop -- since I fly mainly 3D this is my benchmark.
A good TT46Pro with Tower/GMS47 muffler will turn one of these at a hair over 14,000 RPMs on 5% nitro.
I expect that the 12x4 APC is a similar load to the 11x6MA -- if that's the case then the figures you quote aren't too impressive for a.56-sized engine. My ASP52 turns a 12x4 at about 14,400 RPMs on 5% nitro.
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RE: JBA .56
Here's a couple of big detailed pictures of the new JBA 56F.
I cant believe Im saying this but the build quality is actually seems good.. pretty darn good..
If its as powerfull and reliable as the OS 55AX - It'd be a very nice and cheap alternative..
I wonder if it can turn up some revs.. Or do only get away with 12.**x3.** apc 3D prop
I cant believe Im saying this but the build quality is actually seems good.. pretty darn good..
If its as powerfull and reliable as the OS 55AX - It'd be a very nice and cheap alternative..
I wonder if it can turn up some revs.. Or do only get away with 12.**x3.** apc 3D prop
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RE: JBA .56
Heres a better Exploded View:
http://i7.photobucket.com/albums/y27...quid/56FEV.jpg
right click - "save as" to view in full resolution.
http://i7.photobucket.com/albums/y27...quid/56FEV.jpg
right click - "save as" to view in full resolution.
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RE: JBA .56
Hey Guys,
I ordered a .39 & .56 last monday from [link=http://bj-model-engines.com]BJ's Model Engines[/link] ( they had the lowest prices I could find) three days later they were on my doorstep, I needed the .39 for a 40 size Piper Cub and did not have any time to properly break it in. So I just put it on the plane and ran it really rich for the first couple of flights. Let me tell you this engine "Rocks". I had a TT Pro on it before and the JBA blew its socks off. It had alot more power than the TT. I would definitely recommend JBA engines...
I ordered a .39 & .56 last monday from [link=http://bj-model-engines.com]BJ's Model Engines[/link] ( they had the lowest prices I could find) three days later they were on my doorstep, I needed the .39 for a 40 size Piper Cub and did not have any time to properly break it in. So I just put it on the plane and ran it really rich for the first couple of flights. Let me tell you this engine "Rocks". I had a TT Pro on it before and the JBA blew its socks off. It had alot more power than the TT. I would definitely recommend JBA engines...