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Old 10-21-2011, 04:54 PM   #16
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I've never seen a motor go bad at that temp unless somthing freekish happend. What ends up destroying the motor is one of three things.

1) The Rotor looses its magnetic force so the motor looses power and starts heating up more because it cant handle the same gearing it once could. If you catch it in time replacing the rotor will keep this from happening. Rotors generally start to wear from long term use or from getting to 200+ more than a couple times. The hotter the rotor gets the more magnatism it looses.

2) The solder in the windings melts, occasionally this can be fixed but warning will robinson, if it got in the wrong spot it will destroy your ESC the next time you plug it in.

3) The Epoxy in the windings has melted. This is the most common reason a motor goes bad from extreme over heating. The epoxy is the same in all motors and melts down at the same temperature so there is really no one motor brand that is more tollerant than others but occasionaly you get a fluke motor that is more or less tollerant that can be from any of the manufacturesAll in all I've had the best luck out of Trinity motors

TRUE.
There are different grades of magnetic wire.Some will take higher temperatures then others for a higher price of course.

The earler Novak SS motors were made with a higher grade temperature wire.
I've seen some of these motors sell for over $120.00 each


Today companies are using cheaper wire to make up for the higher cost of
rare earth magnets (rotor) but brushless motors cost is going up.
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Old 10-21-2011, 05:07 PM   #17
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My X12 came off after 5 minutes and a broken fan wire at 105 celsius, could feel a lower speed after 4 min racing.

but next round it was fine again, running around 75/80 celsius usually
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Old 10-21-2011, 05:10 PM   #18
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still useful to know at a quick glance if you reached the "ugly"
Good Point!
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Old 10-23-2011, 10:23 AM   #19
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I was in disbelief that you could have not done somthing wrong to that revtech motor and had it burn up at 160* or lower.. I now retract that statement. I had a 1 race weekend old Revtech go bad on me saturday that had never gotten above 140* in fact the first time I noticed it had a "burnt" smell and had gotten slow on me at the end of a race the can temp was 110* and internally it was about 140* (mesured through a vent) The motor over the next 3 runs got worse and never came off the track internally higher than 160* and externally it was about 140* Ran in blinky touring at the last timing mark with a fan blowing on it (as soon as my run was over I ran to the car and unplugged it to keep the fan from cooling it down. ambient temp was just shy of 70*)

I have NEVER seen a motor that was this much of a flake. I've always bashed the novak stuff because I've seen similar results from thier brushless motors but never this bad.
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Old 10-23-2011, 11:13 AM   #20
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I was there at the track when the motor Bubblehead is referencing went up in smoke. The guy that it happened to is a local hot shoe, knows his way around motor and esc set up very well, and takes VERY good care of his equipment. One winding was burned up pretty badly. Looked like an old brushed motor that was way way WAY over geared (if you've ever done that, you know what kind of mess I'm talking about! )

There seems to be an alarming trend popping up all over this and other posting boards about the RevTechs, especially in boost. First the issue with the screws (too tight and you have problems, and they seem to loosen up 'mysteriously' unless loctited in place with VERY little torque), now it seems that they're not performing with any longevity with boosted profiles, either.

I begin to wonder if it's a design problem, materials spec problem, QC problem, or if we've finally found the limits of torque/RPM/effeciency/amp draw with the current paradigm in motor design. Maybe the RevTech trades too much heat tolerance/timing tolerance/whatever for it's low end torque and improved RPM range. $90ish is a lot to pay for not knowing.

I know, I know, I know....everything has some growing pains. That's what R&D is for, not your friendly local hobby store track on race night. Wanna play "Bet your entry fees" with YOUR motor?

Seems like the D3 is the thing for boosted or a lot of added timing(for blinky) and the RevTech is for blinky with endbell timing, but the Rev isn't living up to it's promise. I'll take a D3 or an X12 and a few more teeth on the pinion until this gets sorted out.

Too bad tuners like Fantom are already abandoning the D3 in favor of the RevTech.
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Old 10-23-2011, 11:19 AM   #21
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Too bad tuners like Fantom are already abandoning the D3 in favor of the RevTech.
I dont blame Jeff (owner of Fantom) he's a good guy and running a hobbyshop in GA I deal with him a lot. His problem is if he's not tuning/working on the hotest motor of the week he is not selling anything, and the revtech was it. He couldn't forsee the problems with it and in the grand scheme of things he is not a big operation. He doesn't have the disposable funds to have 3 different brands of motors all at the same time to be working on. He just has to hope that he made the right desicion at the right time. Jump on things to early and you get this, but an hour late and he doesn't sell anything that he already has invested in. Its a catch 22
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Old 10-23-2011, 11:49 AM   #22
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You are correct on that. The revtech was designed for blinky racing. If you are going to use it in a boosted type application, get a D3 (motore that the revtech is based on). I use two of the 13.5 ones and have had several 190-200 degree runs on each and they are still working flawlessly.
so thats mean the trinity revtech motor will not be good choice if in boosted condition? im about to buy the revtech 10.5t, help me
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Old 10-23-2011, 12:51 PM   #23
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so thats mean the trinity revtech motor will not be good choice if in boosted condition? im about to buy the revtech 10.5t, help me
I think with problems people have been having (in both boosted and non boosted classes) your best bet is to get the Duo3 motor. For what its worth Hara was running a Reedy Sonic 17.5 at the IIC and won, thats the next motor I'm going to try. I got the Revtech to replace my ageing duo3, and because it matched the RevTech 28c lipo I orderd to add some orange to my car. The battery is great, but I won't buy another Revtech motor
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Old 10-23-2011, 12:58 PM   #24
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there is the possibility of a poor wiring batch used in some of the motors or epoxy etc...
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Old 10-23-2011, 03:38 PM   #25
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I just left the track, after 4 laps my car started to slow the temperature of my motor was over 200*. Blinky ReVtech
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