Novak Sintered Rotor

[torque5252]

Just wondering if I should bother to upgrade my 8.5 xbr. Anyone have some insight into this? Faster, stronger, etc? Thanks...........torque:D

[GordonFreeman]

I would also be interested in some intelligent comments about this rotor. Here is my understanding:

1. Stronger magnetic field.
2. Smaller diam. (lessens the stronger magnet, larger air gap)
3. Stronger structurally (higher RPM capable).
4. Net cogging seems slightly higher than a regular rotor (net of stronger magnet but smaller diam.)

What does all this mean? Don't know. What does it net for power changes, torque, efficiency? Don't know.

I once stuck a Fiegao rotor (same size as the large Novak, but the super high power magnet like the sintered) in a Novak can and the system would not start up. It (Novak ESC) did not like it.

[AE_racer38]

Talk to anyone who had the original SS system with the 5800 motor. It was notorius for going into thermal overload. With the sintered rotor in it, thermal issues are a thing of the past. Even with the new XBR system, the stock rotor is more likely to thermal than the sintered rotor. Also, gearing is less of an issue. Before, you had to run a small pinion to prevent thermal issues. With the sintered, you can gear it like you want.
It is much more efficient, produces more power (watts) and torque, so you can gear it for the track instead of gearing to prevent a thermal. It is worth every penny, and yes i use it in my XBR 8.5.

[ElectricThunder]

I upgraded an original SS5800 with the sintered rotor, and then sent in my SS ESC to be upgraded to an "XBR with SS+ firmware".

Sooo, what I noticed was a very cool running motor, plenty of torque, and the ESC ran a good 20 degrees cooler. I haven't run the setup in a while though. I can get a few runs in this weekend if you want since I'm going home after finals.

I'll take some temperatures of how it runs in my TT-01.

[torque5252]

E-thunder, I'd appreciate that. Seems like a good performance gain for not a lot of cash.

[ElectricThunder]

I'll get on that this Saturday and/or Sunday for you.

FYI- I will most likely be running GP3300s in the TT-01. I'll probably run a pack all the way through and take some temperatures. If I remember right, gearing for the TT-01 is a 19 tooth pinion and whatever the stock spur is (FDR is around 7.5:1).

[ElectricThunder]

Okie dokie. Terribly sorry it took me so long to get this information to you, but here we go!

Here's my setup and conditions of this particular run:

-Tamiya TT-01
-GRP Foam tires all around (35 front, 45 rear)
-FDR is I think around 7.5:1 (probably a 21 or 22 tooth pinion; ignore what I said about pinion choice in the above post- I haven't touched this car since the Christmas break let alone opened up the gear cover)
-GP 3300 "SPT" (solderless power tube w/ silver paste; these batteries are about 2 or 3 years old IIRC and were charged at 3.3 amps for 1 hour and 4 minutes)
-Franken-ESC (it's an XBR with SS+ firmware)

Now on to the good stuff (after an approximately 15 minute run):

Motor temperature- 113F
ESC temperature- 92F
Battery temperature- 106F

The run consisted of WOT passes, plenty of donuts, as much stop and go on the high traction asphalt (trying to get the current draw up there) as I could bear, and in general just abusing it and getting on the throttle as much as possible. The car was good for a VERY quick 40mph when the pack was fresh off the charger.

I ran it about 20 minutes ago, so the sun was not out. Dead calm too; not a whisper of a breeze at all, and the outside ambient temperature was approximately 73-75F according to my desktop gadget on my sidebar. Humidity made it feel like it was about 77F though.

If I left anything out you were looking for, let me know.

The car would just ROCKET to top speed on the high traction sidewalk, so there is no shortage of torque at all. On the asphalt, I broke loose quite easily and could drift around a corner on the black asphalt of the street. If I rolled on the throttle, it would quickly hustle to get to top speed and was quite manageable. I can only imagine how it'd be with my 2s lipo....:D

Needless to say, I could certainly gear up and it wouldn't kill the motor or ESC at all.

[torque5252]

so no apology necessary!!!...and thanks for all the info, you're very thorough. I'm running a T4 and not nearly as abusive as that! After a 5 minute run on our local offroad track (geared fairly low) and trying to drive smoothly:p, I'm getting 125-135F on the motor. Haven't temped the esc or batts as I'm not thermaling and my packs(matched GP3300) are cooler to the touch than my Cyclone-12T combo was getting them. Sounds like that rotor will drop my motor temps and get me some more ooomph.:eek: I've spent more than 35 for a lot less gain I'm sure!!!:rolleyes: Thanks for all the help, I'm sure bashing that TT around with this setup was a lot of hard work!!!:D I appreciate your sacrifice! LOL later...............torque

[ElectricThunder]

No problem....:D

To be fair....it DID take time away from me testing my new motor in my Rustler, or my new helicopter....:p I'm willing to make sacrifices though...;) HAHA!:D

I think the rotor will do your T4 some good for sure. Gearing options will be a little more liberal too with the new rotor.

Alternatively, if you want some monster torque and even cooler temperatures, you could try the tuning rotor instead (it is 13mm vs. 12mm of the "regular sintered rotor"). Might be a bit overkill though for racing.