I’m sort of moving a discussion that got started over on the ROAR Nats thread but then dried up. But it was in the wrong place anyway.

Has anyone else done any real dyno testing with the brushless motors and can post their readings along with each motors MuH number? I think if we can get enough data, then we can start to determine how much 1 MuH affects a motors performance.

How much are you paying for that kind of info? I take Paypal.......

does it really matter NOPE you'll never see the difference on the track.

instead of all you guys sweating the inductance why don't you pay more attention to finding that optiimum rollout for that motor.

From data comes knowledge, from knowledge come usable rules and rules are the one thing we are short in when it comes to brushless lipo racing.

I'll say what I've been saying forever. Inductance is a terrible way to gauge performance and bad way to do tech if it's your only tech tool.

No one will listen though so why bother.

All the knowledge about what inductance is and how motors work is avaialbe in the internet. Google it.

agreed 1000% Pat


I just think to many people are caught up in the "numbers". It seems now adays that everybody is going to the track thinking that they must have the lowest possiable inductance with the higest rotor. then when they get beat they think that the other guy is cheating.

honestly 90% of us need to come to terms with our abilities. admit that we aren't "the wheel man or the wrench we think we are"


i think that 90% of the rules that have been created for brushless lipo racing are "feel good" rules and not necessary.

what I am getting at is you guys need to realize that no matter what you do and what you buy you'll never be as good racer x .

you can't buy talent.

GUYS..........all I want is some information........geeeees!

There are three things that influence inductance, number of winds, shape of the coil and permittivity of the core material (stator laminations).

Why is inductance a bad way to set rules?
All you are interested in for rules is the number of winds and gauge of wire, but there is more that affects inductance than the number of winds. (see above) There is no way you are going to accurately determine what inductance is "legal" or "not legal" by getting 10 motors from a manufacturer all out of the same lot and seeing where they read. Even with a 21.5 one turn more or less will be a fairly large jump in inductance. If you say 36uH is legal then you can't say that 35.8 is illegal. It just doesn't work or make any sense. This is the fundamental reason why you'll continue to see problems at races with the rules written as they are.

Inductance is simply a clue that something is not right. Here is what tech should be.
1. Motor doesn't look right on the track
2. Motor is examined visually and with an inductance meter. if the motor appears tampered with it gets torn down. If the motor appears ok but inductance is significantly below the norm it gets torn down. If the motor looks fine and inductance is a smidge low than the motor is fine.
3. Tear down the motors that meet the criteria above and count the turns. This is the last only word on legality.

As for performance, inductance has absolutely no direct relation to performance. If a motor has fewer turns it will have lower inductance and will perform better. If the motor has a more permeable stator material it will have HIGHER inductance and perform BETTER. You won't see inductance as a variable in any electric motor equation.

Mclin:
What Pat and Dave stated is pretty spot on. Let me give you an "old school" example that we can all relate to-a little long to read, but bear with me.

Checking Inductance in R/C motors isn't anything new. I have utilized an LCR meter since Neal McCurdy introduced one to me in the early 90's @ Trinity-and it stayed in the box more than it was on the bench. I did use it a lot years later when ROAR had a 10 turn limit for On-Road, which was enforced by checking inductance.

In the months leading up to the Snowbirds one year, I was performing all my normal motor preparation- gaussing magnets, checking air gaps, saving all the thinnest hysol / best balanced arm blanks to wind on, etc;

After I would the arms, I checked all the arms for inductance, saving the best for the Birds. These would be built with the best components I had saved as well, such as cans, magnets, etc;

In testing prior to the Birds, I had rented a track and was testing with the Putnam team, running the worst cans and arms I had-saving the best stuff for the Birds- just testing chassis setups, cells, etc;
Based on gauss and inductance numbers, the stuff we were running was terrible by "National Level" standards- magnets were misaligned with gauss and inductance #'s all over the place. Polimeda hung 3 laps on that track's record. He insisted that I bring that motor to the Birds, I agreed, against my better judgment.

We went to the Birds with that motor. Frank wanted to atleast practice with it, and I agreed, figuring that as soon as it got it's face kicked in by what Dieter and Reedy showed up with, he would then ask me to put in "a good motor."

Polimeda effortlessly dominated practice, TQ'd and Won 6 Cell Mod- both by over a lap...with 68 seconds left @ 35, when the majority of the field dumped. No one was within a lap of us all week.

That motor was incredible. It out performed every other motor in the field in both power and efficiency all week -

Based on inductance and gauss numbers, among other things, I would have never had run that motor. If I ever disclosed how many Snowbirds that motor went on to win for various other companies, I would be burned at the stake.

Point being, numbers on the bench- high or low-don't always correlate to high or low performance on the track. :thumbsup:

Mclin:
What Pat and Dave stated is pretty spot on. Let me give you an "old school" example that we can all relate to-a little long to read, but bear with me.

Checking Inductance in R/C motors isn't anything new. I have utilized an LCR meter since Neal McCurdy introduced one to me in the early 90's @ Trinity-and it stayed in the box more than it was on the bench. I did use it a lot years later when ROAR had a 10 turn limit for On-Road, which was enforced by checking inductance.

In the months leading up to the Snowbirds one year, I was performing all my normal motor preparation- gaussing magnets, checking air gaps, saving all the thinnest hysol / best balanced arm blanks to wind on, etc;

After I would the arms, I checked all the arms for inductance, saving the best for the Birds. These would be built with the best components I had saved as well, such as cans, magnets, etc;

In testing prior to the Birds, I had rented a track and was testing with the Putnam team, running the worst cans and arms I had-saving the best stuff for the Birds- just testing chassis setups, cells, etc;
Based on gauss and inductance numbers, the stuff we were running was terrible by "National Level" standards- magnets were misaligned with gauss and inductance #'s all over the place. Polimeda hung 3 laps on that track's record. He insisted that I bring that motor to the Birds, I agreed, against my better judgment.

We went to the Birds with that motor. Frank wanted to atleast practice with it, and I agreed, figuring that as soon as it got it's face kicked in by what Dieter and Reedy showed up with, he would then ask me to put in "a good motor."

Polimeda effortlessly dominated practice, TQ'd and Won 6 Cell Mod- both by over a lap...with 68 seconds left @ 35, when the majority of the field dumped. No one was within a lap of us all week.

That motor was incredible. It out performed every other motor in the field in both power and efficiency all week -

Based on inductance and gauss numbers, among other things, I would have never had run that motor. If I ever disclosed how many Snowbirds that motor went on to win for various other companies, I would be burned at the stake.

Point being, numbers on the bench- high or low-don't always correlate to high or low performance on the track. :thumbsup:


to translate this brillant post into something we can all understand. stop worring about numbers concentrate more on rollout for your motor, car set up, radio settings, and driving clean lines

to add to some of the comments here - with all the crap and griping I've seen and heard over these motors...I haven't checked ANY because "On the Track" (Where it COUNTS) I have not seen ONE single event of ours that I feel was WON by MOTOR.

These guys know how to find stuff...just like the guys on the other coast...and I'm sure it can't be bacause they just simply want to RACE as FAIR AS POSSIBLE - yet our racing has been SO much closer, and we've had several guys who use to be lower on the ladder, climb higher...(I won't say they are up top - but the improvements are measurable)

...I personally think/feel SOMEONE/SOMETHING is behind the BAD stuff that's been being created...and I think there is a specific purpose for IT.

...I personally think/feel SOMEONE/SOMETHING is behind the BAD stuff that's been being created...and I think there is a specific purpose for IT.

Yup...the weekly B Main top qualifiers!

OK, now that everyone has told me that I don’t need to know this, let me ask you guys something. How does ROAR qualify or disqualify a motor in pre tech at a big race? What was the first thing that a local track owner bought to tech there racers motors?

I could really care less what the inductance reading is, in fact THAT was the point of this whole exercise, to show that one uH in inductance is so small that it means very little, much less .3 or .4 uh. Until SOMEONE sits down and makes a comparison as to what the difference is in torque, RPM and HP between various motors with different uH readings so that everyone SEES how small the difference is, everyone will just have to keep jumping through hoops and believing that the uH rule is the way to go. They will also have to hope that the new motor that they just bought off the shelf will fit somebody’s rule for what a legal motor is.

But you're right, we don’t need this information; thanks for your input.

i thought this thread was about horrible QC on novaks part?

concentrate on the real problem........

they can't duplicate what they sent to roar to have tested....i still think they hired kisbey at a very low pay rate and promised him a raise for good behavior....

i'm not worried about .1 vs .7 on a meter.. what worries me is why can't novak produce the same motor they sent to roar? thats it in a nut shell

NO this is NOT a thread on ANYONE’S Quality Control. If you want to talk about that, start one!

And PLEASE don’t be presumptuous enough to advise me on what you think I need to concentrate on!

And if you are not too worried about a few points of uH, then I hope you are well within your tracks guidelines if you ever get teched because that is what the rules are as of now.

I HATE explaining myself on something like this, BUT all I wanted to do was to see how valid ROAR’s and EVERYONE ELSES rule is when teching motors and the only way you find these things out is with some testing and information gathering. You guys are already saying the uH test is not valid. SO HOW ELSE DO YOU PROVE IT TO GET A RULE CHANGED?

Hank, Close the thread please. This is ridiculous.

...I personally think/feel SOMEONE/SOMETHING is behind the BAD stuff that's been being created...

ya they're called DavePull and Katf1sh

i just call it like i see it......

not a single person has come up with any answers as to why novaks motors did not meter out legal at the nats?

they submitted 5 motors to roar and roar bought 5 motors from the LHS..they took the lowest single reading of all 10 motors and dropped that by 1 full point..a few months later none of the new motors can even sniff those numbers.....that is my only question and it has nothing to do with roar and there rules..i honestly feel bad for roar they got pie in the face at the nats....


lucy you got some xplaining to do............

McLin roar has rules they are on the roar web site..they listed the min inductance reading allowed.....86% of the motors at the nats did not comply with roar rules...

who cares about rules anymore? if roar who stes the rules and puts the numbers on paper can't enforce the rules because the manufacturer can't provide legal motrs to the racers than what does it matter?

it's obvious to me that inductance readings now can only(maybe) be used to find a true cheater motor something way way way off the charts.....because we keep going back and re writing the rules before the ink is dry....why? because novak can't control what they sell....

we can't worry about .1 or .7 anymore.....we just need to keep buying mootrs at each race to keep up with the changes they make at the factory...

you can preach up and down that .1 and .7 are no different on the track...but every oval racer knows they want the lowest reading available...we pay 20.00 more a pack for .1 difference...guys are selling 1380 rotors for 200.00 there are racers out there who care about .00001 sad but true......do i expect novak to produce the same number on every motor over and over? no

do i expect them to at least try to keep them close? yes

brushless and brushed are no different it appears...someone will get lucky and get a realy stout motor(like putnam) and some of us won't....

just make roar legal motors thats all i ask.....

noone is providing real numbers on here because it would only add to the drama..

if i told you i had a prop dyno and

34.3 motor A was 13750 rpm
36.5 motor B was 11797 rpm

we can't do anything about it...both motors according to roar are legal

end of a sad story

call me what you need in order to make yourself feel better when you wake up in the morning....

belive it or not i have no agenda for or against novak.....

i am being told i have to run a novak motor........i want novak to titghten up there QC ASAP! at the moment with them lowering the inductance readings every production run soon 10.5 will be 6.5 no one seems to care?

do i run out and buy 200 motors and rotors? nope never will never have

will some guys do it? yes and it will always leave doubt in the have not heads....

we all thought we had motors that were "close" in grouping....this year with all the teching being done we know the real story.....

no sense worrying about readings when they lower the limits to accomodate the motors.

ya they're called DavePull and Katf1sh



gee thanks Tommy next time warn me before you push infront of a bus.


Sorry if am sick of these threads. and sorry if the truth hurts

People now adays seem to think that the are all "the man" when it comes to wheel and wrench they so up to the track every week with the prosumption that they are getting cheated. guys get beat instead of congratulating the guy the say "he's cheating"

Inductance is useless as a final tech tool all it does is get you in the ball park.

all of these things have a roll in inductance. wire type how tight or loose the windings are, what are the windings coated with. so you can have 2 motors with the exact amount of wire and there inductance is way off.

ya they're called DavePull and Katf1sh



Oh yah Tommy ,

TP and psimkins are both saying the same thing I am so I guess that there trouble makers too.

lol. I mostly meant kat if it's any consolation. lol.
I was thinking of the birds thread you started. That just blew way out of proportion.

oh, by bad stuff being created, I meant the negativity towards novak. I think racing is the best it has ever been with Brushless/NiMh, now is one of the best times ever to be racing R/C.

damn tommy it is getting lonely under the bus now that dave is gone!

well thanks Tommy but I am kind of with kat on this one except one twist I'm sick of the inconsistancy in Novak's manufactoring and would rather just open up the motors.

...ok, so novaks MOTORS are inconsistant (Were TRINITY STOCK motors MORE consistant?) Who knows..inductance wasn't a TECH factor. The NUMBER of WINDS and the +/- was.

Why can't/shouldn't the B/L motors have to conform to the same type of rule.

WIRE DIAM.
WIRE LENGTH
# of TURNS
TYPE of WIRE
Plus a BLUE PRINT 'SPEC' on ALL other components.

Let the CHIPS fall from there...

If the rules set forth

ONE Type Of Wind
Sensored Type Motors Only and incorporate the above guidelines in SIZE, SHAPE, DESIGN, ETC. shouldn't that put all MFG's in the same basket?

Personally, until ALL MOTORS are CREATED in that manner, I will continue to support the SINGLE MFG. Rule.

BLUE PRINT DESIGN for RULES - Lets anyone who wants to build a MOTOR off the BLUE PRINT...Build IT. (Isn't that pretty much how BRUSHED motors were for YEARS and YEARS???)

joe great great great post!

and lord knows if we (joe racer) knew we could meter every stock motor we bought and other racers motors i think(i know) i would be complaining that one stock motor is way different(on the meter) from the other motor.....

problem is right now(today) we are using a number to tell if a motor is legal or not..
than we (the racer) determine if the guy with the lower number means he is faster...

and because brushless is so new to most of us(the racer) we have no idea how to judge if one motor is faster than another...

OK, now that everyone has told me that I don’t need to know this, let me ask you guys something. How does ROAR qualify or disqualify a motor in pre tech at a big race? What was the first thing that a local track owner bought to tech there racers motors?

I could really care less what the inductance reading is, in fact THAT was the point of this whole exercise, to show that one uH in inductance is so small that it means very little, much less .3 or .4 uh. Until SOMEONE sits down and makes a comparison as to what the difference is in torque, RPM and HP between various motors with different uH readings so that everyone SEES how small the difference is, everyone will just have to keep jumping through hoops and believing that the uH rule is the way to go. They will also have to hope that the new motor that they just bought off the shelf will fit somebody’s rule for what a legal motor is.

But you're right, we don’t need this information; thanks for your input.

Post 8 and 9 answered your question. I'm not sure what else you're looking for.

You're not going to get any data because no one has purchased enough motors nor has accurate test equipment to give you reliable data. Without that you'll have to trust physics I guess.

Like I have said many many times. Inductance is not proportional to motor performance in anyway shape or form. It is bad way to set rules and the longer people stick by these silly rules the deeper the hole is going to get.

Post 8 and 9 answered your question. I'm not sure what else you're looking for.

You're not going to get any data because no one has purchased enough motors nor has accurate test equipment to give you reliable answers,

I do!

No you think you do.

A sampling of 10 or fewer motors is meaningless to me as is dyno data. Unless you want to show me a measurement system analysis.

Nonetheless like I said inductance doesn't correlate to performance.

If I took a wind off a motor it would weigh less. Does that mean that motor performs better because it weighs less? Nope, it performs better because it has one less turn. Same principle with inductance, it's an indirect relationship. There are factors which increase inductance and increase performance as well as other factors that decrease inductance and increase performance. You can't pull out a relationship.

Can I get a AMEN for Brother Psimkins

...the following is only a theory! I have no problem with Novak...yet.

With all the rumors of the "other" motors being 1 - 2 laps faster, could it be that Novak is trying to make their product lines competitive without anyone "noticing" in preparation for open motor rules?

that is a very good possability but if that is true than how do you justify keeping it Novak only because the newer motors would be better than the older ones.

I think that keeping a class like 21.5 one motor is a good idea just which 21.5? but for the other classes like 10.5 I don't see how you can go another season shutting the other manufactors out.

No you think you do.

A sampling of 10 or fewer motors is meaningless to me as is dyno data. Unless you want to show me a measurement system analysis.

Nonetheless like I said inductance doesn't correlate to performance.

If I took a wind off a motor it would weigh less. Does that mean that motor performs better because it weighs less? Nope, it performs better because it has one less turn. Same principle with inductance, it's an indirect relationship. There are factors which increase inductance and increase performance as well as other factors that decrease inductance and increase performance. You can't pull out a relationship.

Yes I do!!!!!

Yes I do!!!!!

He said you didnt flack, so you dont. Lol these dudes flack... :thumbsup:

Check your email flack. :wave:

Maybe everyone should just race and have fun, and stop crying about motors!

Yes I do!!!!!


then post the results man

I made a statement like those made here a while back and I was told I was nuts.

Mainly about the inductance readings.

If the motor specs are written to say X number of strands of X guage wire for X turns with a min of X length. X amount of maximum timing and the magentic material on the rotor can be such-and-such material. Can specs, max and min rotor specs. Why can't we allow Billy-Joe to wind motors? Ya know what, if I can build a motor within those specs and do it better than you, one of two things happens. You go back to work or I kick your butt on the track.

Dave -- you nailed it. Too many are not in touch with thier level of talent. Being driving, setup or a combination of both.

We have gotten OBSESSED with making everyone feel good, trying to make sure everyone has a shot at an A main win. Well guess what, WE DON'T. Some of you guys are better than the rest of us.

The next thing you know some doofus is going to suggest we go to bracket racing.

then post the results man

I will bet that there are several guys out there that have quite a bit of data. Maybe not on "Lab" equipment, but on repeatable test beds.

I know Jimmy, if he says he has data, he does. We have raced alot together and way back in the day had more log books on stuff than I really care to admit to keeping up with.

You do not really need a "Lab" to test and see what you are looking for. Just a repeatable test bed. Of course all of this is useless unless you test it on the track. The track will tell all.

I do agree with you Dave, about throwing out the inductance stuff. Specify the winds, length and magnetic material.

Of course other motors are going to be faster with the same amount of turns. The "standard" is Novak that all others are compared to. If you know the standard, it is easy for another manufacturer to make a better motor (considering it is based on a 5 year old design).

Since all other forms of racing allows other manufacturers, Novak will HAVE to increase the performance of thier motors or risk being obsolete.

good post hank and thank you for leaving the thread to fight on another day...

again mr. flack will not provide any numbers for us...it would just make thing alot worse..

half of you guys would say he is not a electrical guru so his info is crap..

the other half would run out and buy what it takes to have a fast motor on the dyno..or switch to nitro racing....lol

Maybe everyone should just race and have fun, and stop crying about motors!

WHAT?!?!??!

Then what we do with all of our time on the 'net? :D

I let it live because I think it provides some useful information. It also reinforces my belief that any single manufacturer rule is not a solution except in a 100% spec class (were ALL parts used for the class is speced).

The single Novak solution was fine as long as they were the only game in town. They no longer are and they will have to increase the performance of their motors. This in itself makes the single manufacturer rules meaningless as their later manufactured motors will out perform earlier product.

These types of rule MIGHT be workable for one more year, but it may already be too late as shown at the Nats. Spec brushless motors like brushed were (turns, wire size, wrap style, magnets, etc.) and let the chips fall where they may. That is the way it always has been.... haven't people said they wanted it to be like it was in the "old" days ;)

I let it live because I think it provides some useful information. It also reinforces my belief that any single manufacturer rule is not a solution except in a 100% spec class (were ALL parts used for the class is speced).

The single Novak solution was fine as long as they were the only game in town. They no longer are and they will have to increase the performance of their motors. This in itself makes the single manufacturer rules meaningless as their later manufactured motors will out perform earlier product.

These types of rule MIGHT be workable for one more year, but it may already be too late as shown at the Nats. Spec brushless motors like brushed were (turns, wire size, wrap style, magnets, etc.) and let the chips fall where they may. That is the way it always has been.... haven't people said they wanted it to be like it was in the "old" days ;)

Excellent. Well said.

great post and the oval gods in florida have just opened up the 21.5 class to any roar legal lipo 3200 .

and the 17.5 class will be any roar legal lipo and motor! woooooooooooo

then post the results man

SEE POST #2

SEE POST #2

Whatever ! ......... why can you just share the info :rolleyes:

...the following is only a theory! I have no problem with Novak...yet.

With all the rumors of the "other" motors being 1 - 2 laps faster, could it be that Novak is trying to make their product lines competitive without anyone "noticing" in preparation for open motor rules?

Stop with the conspiracy theories....

Novak's not doing anything different to increase performance. We have been adding the resistance readings on stickers on the wound stators of our motors. I thought it was inductance, but (after conferring with Charlie) I changed it to resistance.

Anyone notice, or care? The inductance readings have been surprisingly (shockingly!) consistent, given all the accusations and drama here over our bad QC.

than care to explain the roar paved oval nats 17.5 class???????????

NovakTwo, Then please explain how there could be such a difference between the motors that were submitted by Novak to ROAR for inspection to base the induction readings on for the rule book?.

Obviously something changed whether it be your manufacturing process, wire supplier, some process somewhere along the line between when the motors were submitted to ROAR till when all those guys bought their motors.

The problem is this the motors that were submitted for approval to ROAR and what the rules are based upon measured Higher then most of the motors that the competitors brought with them to use @ the Roar oval nats .......... thats a problem.

It's pretty obvious that your motors need to be resubmitted to ROAR so a new benchmark of your consistent numbers can be obtained.

Stop with the conspiracy theories....

Novak's not doing anything different to increase performance. We have been adding the inductance readings on stickers on the wound stators of our motors.

Anyone notice, or care? The inductance readings have been surprisingly (shockingly!) consistent, given all the accusations and drama here over our bad QC.

HaHa...my post was just a theory - it wasn't meant to be negative or dramatic. Hank took it one step further which is where I stood, he just said it better.

Your post turned it into a conspiracy.

While we're at it...is the trade in program good for the "new" motors? :rolleyes:

Whatever ! ......... why can you just share the info :rolleyes:


Senario #1. Cneyedog is a traveling racer to many regional and National level events. Yoe are getting ready for the Nats at the famous Ohsofast Tri-Oval. You have shown up two months in advance and found THE SETUP on the car. You are consistently 1 lap faster than anyone has been and they cannot catch you. They tech your motor and battery every single race, but it is all in the chassis. You have the front end so perfectly matched to the rear end that the car practically drives itself. You have even built a backup car that is equally as fast.

Now with all of this, would you come on here and give away the information you have learned?

I doubt it, so why should Jimmy?