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Old May 30, 2012, 03:37 PM
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Ahhhh..your battery setup makes sense now, if you'd have said it was a 2 pack 5s config I wouldn't have asked, I was thinking you'd found an ingenious way of fitting a 5s pack.

If I'm looking at the same motor, according to the Mega site it's rated at 50a, with special windings on the F5D for high temp. I recently got a 16/25/2 CE (C is 5mm combat shaft, E is reduced kv, about 2300) but done in a F5D spec. Spec sheet I got states the same as the Mega site, 40a, but I'm already running it at about 70-80a in flight. Motor's coming down at about 35 degrees C so it's not gettting too hot, but it's in a FJU so cooling is better than a Simprop TL.
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Old May 31, 2012, 09:50 AM
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I had a 16/25/2 running on 3s 22000mAh with 4.75x4.75 before, and i must of over heated or over amp it because it melted and seized in flight (hence why i asked about spinner angle a few posts earlier).
I was not impressed with that set up, speed was not great on 3s never got to try 4s, which i think would have been much better.
I managed to get a heat sink on the F5D and made a small air scoop to try and help with heat.
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Old May 31, 2012, 12:25 PM
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I'm surprised you burnt it on 3s. I damaged mine during static testing and had to have it rebuilt. Do you think you might have damaged it in the same way? I tested too many props without it cooling properly in between the prop tests. A heatsink will help, as will your scoop.
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Old Jun 01, 2012, 12:09 AM
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Quote:
Originally Posted by savneo View Post
I had a 16/25/2 running on 3s 22000mAh with 4.75x4.75 before, and i must of over heated or over amp it because it melted and seized in flight (hence why i asked about spinner angle a few posts earlier).
I was not impressed with that set up, speed was not great on 3s never got to try 4s, which i think would have been much better.
I managed to get a heat sink on the F5D and made a small air scoop to try and help with heat.
Burning that motor with such a small load is pretty shocking. I think something else must have been wrong, perhaps a bad solder joint in your bullet connectors. Or you were flying on the surface of Mercury.

http://www.rcgroups.com/forums/showthread.php?t=1234521
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Old Jun 01, 2012, 05:39 AM
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Some guys use the 16/25/2 with 4,7x4,7 at 6S!!

http://www.rc-network.de/forum/showt...=1#post1471287
Yello
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Old Jun 01, 2012, 09:42 PM
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Yeh, I think the bearing seized before it burnt

16/25/2's are tough little motors, 5S and 4.75x4.75 is a pretty standard F5D setup.


BTW, the difference between a 16/25/2 and 16/25/F5D is high temp assembly (and the green can) of the motor, the wind and magnets are identical.
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Old Jun 02, 2012, 12:17 AM
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Quote:
Originally Posted by jackosmeister View Post
Yeh, I think the bearing seized before it burnt

16/25/2's are tough little motors, 5S and 4.75x4.75 is a pretty standard F5D setup.


BTW, the difference between a 16/25/2 and 16/25/F5D is high temp assembly (and the green can) of the motor, the wind and magnets are identical.
Im going to maiden the repaired simprop TL with the F5D green motor, what do you suggest i set the max amp at. Bering in mind i will be running it with 5s 1800mAh 20c batteries and a 4.75x4.75
thanks
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Old Jun 02, 2012, 12:20 PM
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Maiden flight today (after nose cone repair). Launch was easy and the speed was great on 5s. Well happy with the results. I set the motor @ 40amps
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Old Jun 02, 2012, 03:19 PM
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How are you setting the motor at 40a? Are you using your tx to limit the throttle, i.e. 50 or 60% of throttle travel?
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Old Jun 02, 2012, 04:23 PM
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How are you setting the motor at 40a? Are you using your tx to limit the throttle, i.e. 50 or 60% of throttle travel?
Yes, I use a clamp meter to measure the amp draw as I throttle up. At Approx 45% throttle it gave me 40amps static.
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Old Jun 02, 2012, 04:29 PM
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Dont do this


Good way to cook your esc, run 100% throttle, your esc will run cooler.
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Old Jun 03, 2012, 01:12 AM
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Quote:
Originally Posted by jackosmeister View Post
Dont do this


Good way to cook your esc, run 100% throttle, your esc will run cooler.
How do I limit the current if I run 100% throttle?
I run almost 100% with my Heli by changing gear ratios to achieve this. And yes the esc does run cooler at 100%.
I don't really want to prop down.
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Old Jun 03, 2012, 01:19 AM
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Current is controlled by the prop, you dont limit current, you either drop voltage or prop size

4.7x4.7 with a 16/25/2 on 5S will fly 100% throttle the whole flight
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Old Jun 03, 2012, 03:51 AM
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I was going to say the same thing as Jack, don't use end points for your throttle. You're better off gliding and giving the motor time to cool a bit, but it seems you won't need to if it can take WOT on 5s and a 4.7 x 4.7. I can't comment on that but Jack seems to know his stuff. Any doubts, just limit your runs, land and check how hot things are getting. If they seem cool enough, run a bit longer next time. It's a pain in the to do, but so's replacing/sending motor's for repair.

You might want to get an Infra-red thermoeter http://www.hobbyking.com/hobbyking/s...idProduct=8297, useful for checking motor (and battery temps), although the TL means it'll be a little difficult to get a good reading. Aim it through the slotted vents towards the rear end plate and try and get a reading.
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Old Jun 03, 2012, 03:56 AM
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Propping down isn't always as bad as you think either. Running a smaller prop usually means it spins a little faster, which in turn doesn't drop your top speed by too much. Maybe a 4.75x4.25 would help keep the amps lower, or a 4.5x4.1 if it is getting hot.
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