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Old 01-15-2008, 09:34 AM   #16
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Steady there Charlie
1) That's not Charlie. Charlie's screen name is ..."Charlie".

There are other people that work there...LOL...and they do know how to get on the interweb. That's one of the big guys at Novak.

2) Why does everyone on here think that a larger magnet means more power?

That's like saying that since cars turn better with lower ride height, 2mm ride height is faster than 5mm. It's called a "trade-off". If it was all about magnet strength, all the brushed people would have been racing Core Stock motors, rather than Monsters and CO27...
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Old 01-15-2008, 10:16 AM   #17
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2) Why does everyone on here think that a larger magnet means more power?

I don't get your analogy at all.

Don't think just about air gap, think about magnetic strength and magnetic mass. The larger, more massive or stronger the magnet the more power the motor has the potential to generate.
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Old 01-15-2008, 10:26 AM   #18
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2) Why does everyone on here think that a larger magnet means more power?
It was my understanding that the power capability of the motor (not necessarily output, but theoretical capability) is proportional to the surface area of the rotor. That is one reason the longer motor cans can make more power than the shorter ones (where there is direct comparison available, like the Fiegao L xnd XL cans).
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Old 01-15-2008, 01:14 PM   #19
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The ROAR rule for Spec rotors (17.5, 13.5 and 10.5, what ever is chosen) will almost certainly be 12.5mm max diameter.
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Old 01-15-2008, 03:51 PM   #20
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I don't get your analogy at all.

Don't think just about air gap, think about magnetic strength and magnetic mass. The larger, more massive or stronger the magnet the more power the motor has the potential to generate.
You don't get that? (where's the "blink-blink" smiley when you need it?)

"Bigger rotor" doesn't equal "faster". They don't have the same powerband as a smaller rotor...they won't spin as fast. In some cases, they may make some motors in some applications drive differently...and if that works for you in that case...good for you...but there certainly isn't a 1:1 relationship between rotor size and how fast the car is.

You did see the deal the other day where (I think it was) Bob or Adnan that said that all the fast 13.5 guys at the Novak race ran the small rotor...even though they could run the larger one?

I understand the need for rules...I just don't get why people on the web always seem to think that if "1" is good, then "2" must always be faster...like there's no trade-off.

You know...5mm ride height is better for onroad than 10mm...so 2mm MUST be better than 5mm...cause 5 is better than 10...so 2 must be WAY better...like you won't have any down-side.
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Old 01-15-2008, 04:09 PM   #21
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Just cut the rotors to 10mm x 30mm and make everyone retool!!!

Since the rotors will be that small the motors should be smaller too! 480? 300?

I am not trying to start a battle, but I just think with our current technology, we are cramming too much power into everything and it may be killing our hobby. I am for the advancement, so if the power density is going up the most logicially solution would be reduce the volume/mass for both batteries and motors.
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Old 01-15-2008, 04:29 PM   #22
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Its meant to reduce the power of the motor for the spec classes and it works quite well.

Not everyone wants to run spec classes.

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If the rules are going to be bent in favor of an existing company, it should undoubtedly be Novak. They're the incumbent, and were nice enough to lend their motor design to Feigao so they could copy it and resell it to a hundred different sticker manufacturers.
As far as I can tell, the ROAR legal companies are the last companies to enter the brushless market. The rules were written to "make brushless motors competative with brushed motors," but they were also a departure from existing brushless designs. Novak may have been the first to make a car specific motor, but they are not the first to make a brushless that fits in a car. It is sad to see the rules be so restrictive in what can be used.
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Old 01-15-2008, 05:12 PM   #23
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a spec rotor sounds good but how could you do it in tech.
you cant see in a novak motor.
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Old 01-15-2008, 05:18 PM   #24
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a spec rotor sounds good but how could you do it in tech.
you cant see in a novak motor.
You sorta can...the 13mm rotor shafts are grooved for ID purposes. You could easily have a slightly different groove configuration for other rotors.

http://www.teamnovak.com/products/rotors/index.html
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Old 01-15-2008, 11:07 PM   #25
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rule is and will be in the 2008 rule book

12.4mm +/- 0.11 tolerance

therefore, 12.51 is the max and 12.29 is the min

settled?

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Old 01-16-2008, 09:00 AM   #26
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Quote:
Originally Posted by Turbo Joe View Post
1) That's not Charlie. Charlie's screen name is ..."Charlie".

There are other people that work there...LOL...and they do know how to get on the interweb. That's one of the big guys at Novak.

2) Why does everyone on here think that a larger magnet means more power?

That's like saying that since cars turn better with lower ride height, 2mm ride height is faster than 5mm. It's called a "trade-off". If it was all about magnet strength, all the brushed people would have been racing Core Stock motors, rather than Monsters and CO27...
Woke up on the wrong side of the bed?

I thought Charlie was novaks only PR guy, apology to mr anon if you are someone else

First of I'm only talking about spec racing.

The reason everyone thinks a larger magnet means more power is because of the laws of physics

You will get tons more torque & horspower low in the rev range which requires higher gearing. Because the motor is doing less rpm it offsets the added inertia from rotating mass.

It's defunct now anyway because Roar are on the ball this time

I just hope the BRCA will follow suit with their 10.5 rules.

Nice job Dawn
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Old 01-16-2008, 09:04 AM   #27
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a spec rotor sounds good but how could you do it in tech.
you cant see in a novak motor.
The bare minimum you have to do to spec a motor is take the rotor out.

Measure internal diameter/lengh of stack. Rotor diameter/lengh.

Then you can use impedance test to check wind.

The only way to be 100% it's legal is to strip the windings off.

This has been the same for brushed motors from day dot.
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Old 01-16-2008, 11:37 AM   #28
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Woke up on the wrong side of the bed?

I thought Charlie was novaks only PR guy, apology to mr anon if you are someone else
It's not PR, it's about providing accurate information.

Torque is not everything, otherwise all 27T guys would be running P2K and Core Stock motors. Besides...if you want to throw "it's just physics" out there, you should be ready to consider ALL the physics involved, not just the one that supports your "bigger is better" argument.

Generally, I find that when real-world results don't square with a theory, you should reconsider your theory...not ignore reality.
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Old 01-16-2008, 12:28 PM   #29
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It's not PR, it's about providing accurate information.

Torque is not everything, otherwise all 27T guys would be running P2K and Core Stock motors. Besides...if you want to throw "it's just physics" out there, you should be ready to consider ALL the physics involved, not just the one that supports your "bigger is better" argument.

Generally, I find that when real-world results don't square with a theory, you should reconsider your theory...not ignore reality.
Ok you just want to be an arse.

I said the increase in torque would be enough to overcome the negative affects of the rotors inertia. If you just want to twist what I say around then so be it. You win 'Mr Internet Arguing Champion' .
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Old 01-16-2008, 12:41 PM   #30
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Ok you just want to be an arse.

I said the increase in torque would be enough to overcome the negative affects of the rotors inertia. If you just want to twist what I say around then so be it. You win 'Mr Internet Arguing Champion' .
I really don't think I'm the one who's acting like a third-grader here.

Grown-ups tend to see the nuances and trade-offs, while little kids and internet guys tend to always jump to conclusions based on simplistic perspectives.

Rather than calling names, why not just discuss the issue civilly?

Novak motors have the smallest rotors, yet they seem to be regarded as the motors with the best feel, powerband and driveabillity. I don't think I'm going out on a limb to say they've really caught on out there with the kids.

There are larger rotors available for them, but they don't seem to be widely used in higher-level spec class racing. It doesn't seem that the larger rotor makes the car GO FASTER.

That doesn't appear to match with your view that a larger rotor means "better" or "faster".

I wasn't necessarily talking about inertia, I'm talking about RPM range vs. angular velocity, among other things. Sure it makes more torque, but does it have the RPM range necessary to get the job done? Torque and big magnets aren't everything...again...if they were, the Monster 27T would have never been used, everyone would have TOP and Yokomo motors.
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