anthony390

yea those are the dog bones that im talking about

does any body still make them

John Stranahan

iTrader: (27)

Anthony-I think more that one brand of car uses them as original equipment. Don't know of any aftermarket suppliers.

Chris Adams

Thats not what I meant. On the input harness for the brushless system the blue wire is the thermal shut off wire.

John Stranahan

iTrader: (27)

Chris-Thanks for Clarifying. I edited my post. So the thermal sensor is in the motor then. Am I cooling the wrong unit.

AngryAsian

iTrader: (4)

On that note Chris - is there any performance gain from cutting the temp sensor wire? Or just allows you to run the motor hotter?

It's shame about the GTB John... I'm still waiting tot ry the 4.5motor in my car, but i don't get much running now that autumn has set in. Semms like all the weekend are rained out at the moment...

Chris Adams

That I dont know. I know about the blue wire because I am one of the only people that have read about the brushless rules in the roar rule book. It is possible that you should cool the motor. The losi doesn't have the best of cooling for the motor since it is center mounted.

Chris Adams

Guys, I dont even run the brushless stuff so I really dont know. The only reason I know this is because of the rumors of people unplugging the blue wire at the Novak race and the Roar rule book.

Chris Adams

I am pretty sure that you are able to run the motor hotter without the blue wire.

AngryAsian

iTrader: (4)

I read that many people were indeed cutting the blue wire at the Novak race. BUT! the top cars there (excluding the crazy 3.5 powerful monster that charlie was driving) were still running the full sensor harness....

hmmmmm...

Chris Adams

So they tell you. I think it was for the 4300 class. Again, I think that you guys have a cooling issue and there isn't a need to go to such drastic measures. Plus it voids the warranty.

John Stranahan

iTrader: (27)

Angry Asian,Chris-Thanks for the info. I'll try that GTB again in 2-3 weeks. Trim ring will go. Fan on the motor. I personally think the main motor guts would survive at 210 F like our stock motors do unless the sensor circuit is delicate. I should note that I did an experiment at 80 F and ran the first GTB unit without a fan. I got thermal shutdowns, so the speed controller needs to be cooled as well. It always temps at 120 F with a fan.

There is a second picture of the Losi LCD dissasembled on the previous page if you missed it.

John Stranahan

iTrader: (27)

This was probably the last cool Saturday morning. Really good weather this morning. Track temp was 110F at 10:00 AM. CS 32s worked well. Track temp came up to 125F by 11:30 AM. Takeoff RP36 (with traction compound) worked really well on my JRXS. It was hooked up. CS 37's dry were a little slippery on Lins car at this temperature. Track was clean and grip was up. Had a good time. Plan to test some more motors tomorrow. Novak GTX back in the car.

Reedy Krypton 10 x 1
I tested a Krypton 10 x 1. This Reedy motor has a medium size comm. I increased the stock spring tension from 3 on the Trinity spring tension gauge to 3.5 before the first run. Ran it at 7.56 overall. The motor was really fast this way. It was a rocket out of the corners. but was lacking in spring tension as evidenced from the comm wear pattern. It was a little rough after two runs. I think it will need at least a 4 on spring tension and then maybe a little higher gear to compesate.

Trinity Cobalt 11x1
I also ran a Trinity Cobalt 11 x 1. This motor really came alive in going from a 7.56 to a 7.42 gear. So don't skimp on the gear selection. This motor was very efficient for practice. It seemed to run several extra laps at race speed.

Spring tension Increase!
I had an interesting thing happen with Trinity silver springs. I had set a Trintiy Cobalt 10 x 1 motor up with a spring tension of 4.25 and noticed the second day I ran it that it was a little sluggish. The tension had increased to a 5 on the gauge. I guess the spring coils loosened up. Never had this happen with the lighter springs. They always get weaker.

If you want to use this type of spring tension gauge don't forget that you can put the spring on an old stock motor to set the tension and then transfer the spring to your new Sphere or Cobalt II.

John Stranahan

iTrader: (27)

GTB 6.5 Motor Cooling Fan

Here is a pic of my latest install of the GTB 6.5 in the JRXS which includes a motor cooling fan for hot weather. I'll give a test later. I don't know exactly where the temp sensor is, but I suspect its on the Printed Circuit board. I could not get the motor apart easily for a peek inside. I located the fan on the side to cool this end of the motor and to be able to draw cool air from the left front wheel well. Most of the air will blow in front of the motor and then pass over the top and bottom of the motor aided by vehicle motion and air passing under the car. I have seen setups with two little fans on top which I can try next.

This particular fan is a Novak part. It comes with a Y-harness which I harwired under the GTB controller direct to the battery leads. This left me with two plugs to run the two little fans. The fan leads are inside the motor control wire harness. The plastic bracket which I modified also came with this part. It blows a lot of air.

AngryAsian

iTrader: (4)

I hope the fan helps alleviate your motor temp problems. By the looks of it, the JRS has all the "hot" stuff tucked away and surrounded by bits that decrease the airflow. No wonder it gets hot!

I know from experience the novak motor reacts very well to cooling. I run a fan on my motor (one of those cheap integrated heatsink-fan units - but running of battery power directly, not through the ESC) and it does make a difference to the probability of the unit thermalling.

Wouldn't the 4.5 be perfect for your chassis? small machined cooling fins. Not such a great help on cars where the motor is exposed anyway where good contact with an appropriate heatsink is required. But perfect for your car...

Now if they did a black crackle finish - perfect..

P.S - good luck keeping all the blades on the Novak fan. Lots of air but oh so brittle.

John Stranahan

iTrader: (27)

I noticed that some of the Aircraft brushless motors had built in fans with cooling ports. I don't know why that would not work with these units that are made for cars.

I have my small fan protected by an empty fan shroud that will also smooth the intake air flow. I have lost quite a few blades previously on this small fan by having the switch too close to it. My fingers did the damage with the body on. I actually ran this larger fan previously on the speed control unit. It seems to be more durable. I moved the switch away from the speed control fan to the other side of the car. I agree that the JRXS shrouds the motor with the top chassis plate. That's one reason I decided to blow in air from the side. I agree that a black finish would allow for better cooling. I am hooked direct to battery with the fans.

Novak also suggested running a 5.5. I running in a 10 turn or GTB 6.5 class though. I don't understand how having a more powerful motor, that typically produce more heat, would solve the overheating problem.