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Old 07-13-2008, 05:55 PM   #1
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Default JR8711 gets hot

Running on my Berg, my 8711 gets hot.....I mean can't hold your fingers on it for more than a second hot. Running CC BEC at 5.9 volts (was at 6, tried turning down to 5.9 to see if that would help....it did not). I put my EPA's to max, then back off 4-5 points. Steering is free with the servo horn off the servo.

I have used a JR 9100T and Hitec 5955 in this same rig with no issues. I just wanted to try the 8711 (others servos work, so don't think I killed those and am now trying this).

Any thoughts, comments or suggestions would be greatly appreciated.
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Old 07-13-2008, 06:03 PM   #2
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I have the ds8711 in both of my rigs. both with the cc BEC set at 6.0 volts.
one rig runs a mamba micro pro esc and the servo soesn't get hot at all, but my other rig is running the Tekin FXR and the servo gets so hot you can't touch it.
I have no binding in the steering linkage on either rig.

I don't know if the ESC has anything to do with it getting hot but I thought it was wierd myself!

this probably doesn't help you in your question, but just thought it was an interesting fact!
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Old 07-13-2008, 06:09 PM   #3
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It very well may help.....I am running the Tekin FXR, too. Interesting.
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Old 07-14-2008, 03:17 AM   #4
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Quote:
Originally Posted by wrightcs77 View Post
It very well may help.....I am running the Tekin FXR, too. Interesting.
If you removed the red wire from the ESC to the receiver and are running the servo off of the BEC there should be no coralation betwwen the FXR and your problem, but if you did not remove the wire from the ESC that is probibly your problem.
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Old 07-14-2008, 07:12 AM   #5
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How does it do when you set your epa's lower? Id say start off with the epa's turned down and then turn them up as needed to get max throw rather than starting off at max throw then backing off....
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Old 07-14-2008, 07:54 AM   #6
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Quote:
Originally Posted by wrightcs77 View Post
It very well may help.....I am running the Tekin FXR, too. Interesting.
I am running the same set up. My servo never get hot. Adjust your servo travel. I read alot about the 8711 and if you do not adjust the travel it will get smoking hot. I am running Axial axles and I have it set to 88% steering travel, What I did was raise the front of my rig. Then I turned the wheel max right and the started playing with the travel settings, I found that bewteen 89%-100% the steering did not turn any more, so I set it at 88%. What I have read was bewteen 89%-100% the servo is trying to push more then your steering will allow and the servo is getting hot.

I ran my for a hour straight yesterday not even warm to the touch. I am running a DX6.. Hope this helps you.

Last edited by Sinastir; 07-14-2008 at 07:57 AM.
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Old 07-14-2008, 12:23 PM   #7
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I removed the red wire on mine when I installed it.
and I have messed with the epa'a and have had no luck at getting it to cool down any!

now that we are talking about it I am going to check my bec voltage and mess with it some more.
I have just been driving it this way cause I couldn't get it to change.
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Old 07-14-2008, 01:15 PM   #8
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I run my 8711 with a Catle BEC (6v) and a sidewinder and it stays cool. Maybe if the EPAs and voltage are correct it might be time to give JR a call.
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Old 07-14-2008, 04:07 PM   #9
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X2 on calling JR,I have never know anyone running that servo on 6.5 volts having any heat issues.If the 5955 wasn't hot with your setup theres something wrong with that servo.
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Old 07-24-2008, 04:45 PM   #10
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Well, I think I figured it out. The servo horn had too deep of a recess for the servo splines, thus causing the servo horn to rub on the servo. A little dremel to the servo horn and it is all fixed.

Thanks for the help and ideas.
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Old 07-25-2008, 01:35 AM   #11
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Yeah I noticed the dynamite horns are alittle to deep for the jr and airtronic servos. I either use a shim in it or grind it down alittle. I noticed that when its too deep it likes to loosen the screw too!!
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