DARKSIDE

iTrader: (2)

and boom...

http://roarracing.org/4rmb/showthrea...T-W-11-12-2016

TOM MAR

iTrader: (3)

Naw, already posted that link. lol

But yeah And Boom.

howardcano

iTrader: (37)

Neither worked for me. I'm guessing the problem is on my end, though I haven't the slightest idea why!

massenb203

ROAR New Approved motors

http://roarracing.org/4rmb/forumdisp...ec-25-5-Motors

djgrom

iTrader: (1)

That link is getting a real workout.

theproffesor

iTrader: (66)

So the question is...

If the minimum resistance spec will keep these new 25.5 motors from doing what the new 21.5 and 17.5 motors have done.

I'm hoping that it does what was intended and keeps the motors on par with each other, not only from one manufacturer to another, but from generation to generation as well.

howardcano

iTrader: (37)

It's a big step in that direction. There are a few other things that should be addressed in the next rules update, but none are as large an influence.

hotrodchevy14

iTrader: (115)

go with fantom or better
yet motiv

microed

Whatever you get, make sure it has a 12.3 rotor which is the only legal one.

I was looking to buy a new VTA motor recently and I was considering the Hobbywing XeRUN V10, but every online spec I could find (including Hobbywing North America's website) says it only comes with a 12.5 rotor. So that leads me to believe that anybody running one straight out of the box would be illegal. I looked up the rotor part number listed on the ROAR site (http://roarracing.org/4rmb/showthrea...101-05-31-2016) and it says it is a 12.5 rotor.

The other Hobbywing motor on the approved list (Just Stock 3650) appears to come with a 12.3 rotor only which would make it legal. However, it has fixed timing which I think would make it useless for racing.

Kevin Marcy

Most of the rotor testers I've seen (including the one I built) place the rotor in "V" blocks a fixed distance from the sensor. The 12.5 rotor will read as stronger simply because it is closer to the sensor. It may not actually be better magnetic material (and they're illegal anyway in VTA).

jlfx car audio

iTrader: (37)

i agree they do read higher but a normal 12.5 rotor reads 1400ish but the newer tsr,motiv are 1640-1750
apply that same tech to the 12.3 rotor and your looking at a 1400+ 12.3 and thats just guessing .

Kregger

iTrader: (2)

I asked because the OP was asking about the D4.
Unless I read it wrong the D4 25.5 is being listed as roar approved.

Carnage9270

iTrader: (6)

Definitely not ROAR approved. The 24k is though.

Carnage9270

iTrader: (6)

There's no new technology to applying a magnetic charge to magnetic material. What is changed is how much magnetic material is present. This gives the torque you are referring to. Mod rotors use more magnetic material than a stock rotor, that's why the gauss rating is so high. The reason TS and Motiv are using such high gauss rotors is because of the way the stator is made. They are extremely high rpm stators, this needs to be compensated with a really high gauss rotor. The combination works well, but it's not applicable to a 25.5 quite the same way. A 25.5 stator is far from an "RPM" stator like the short stacks.

The only way to increase the gauss rating on a 12.3 rotor is to increase the length of the magnetic material. But roar defines how long that can be (25 to 26mm) as well as the diameter (12.3). So there's not much wiggle room in the rotor department. Like I said earlier, it all comes down to how close to the legal limit the stator is. And frankly speaking, at 101 pole to pole, unless a motor is way off (like 120) you won't notice a whole lot on a 25.5.

The true measure of a 25.5 at this point, at least for me, is material quality. (stator material, wire material, sensor units, case etc). This is where I see a huge difference between manufacturers.

bertrandsv87

iTrader: (2)

I guess 25.5t motors will be getting alot of attention from now on, but wouldn't it be better to gain power by reducing the car's rotational mass instead ???