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Old 09-07-2011, 07:39 AM   #46
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It would be great if the "Turns" rating was ditched for kV range ratings.
I don't think those kv ratings are accurate and sensorless motors are not well suited for on-road racing. I don't understand why you would want this.
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Old 09-07-2011, 07:40 AM   #47
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Been in contact with a lot of the club organizers in Ontario to try and work out more consistent classes. At K.R.C.R. we are doing open ESC 17.5 TC, GT2 21.5 Spec or "Blinky" ESC and a slight variation on SCAR/TransAm/World GT CHALLENGE with R.O.A.R. World GT specs and 21.5 SCAR & TransAm with Spec ESC or "Blinky". Canadian VTA will be the same as Lou's with 21.5T Spec ESC or "Blinky". When K.R.C.R. opens our outdoor track next summer we will add GT1. I'm trying to make it easier and cheaper to switch from outdoor to indoor between clubs. As D.R.C.R.C. is the closest club to us, we will match their classes as much as possible.

It would be great if the "Turns" rating was ditched for kV range ratings.
I agree with the kv's not turn. But i wonder if it would take away some of the competition!
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Old 09-07-2011, 07:40 AM   #48
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What is the difference between super stock and mod?
I'll be cheeky and say several hundred dollars per race day...
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Old 09-07-2011, 08:05 AM   #49
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What is the difference between super stock and mod?
It's usually around 1.5- 2.5 seconds a lap, a rough guess?
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Old 09-07-2011, 08:05 AM   #50
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I don't think those kv ratings are accurate and sensorless motors are not well suited for on-road racing. I don't understand why you would want this.
+1 as the kv ratings are all over the place... I know of some motors being 2200kv and 1900kv and they are both 17.5 turn.
Its how the manufacturers test and make the motor as it is. Then send it away to be tested by the governing body for approval so they are saying it is equal with all the other motors they have seen.
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Old 09-07-2011, 08:07 AM   #51
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Bishop I wouldn't mind at all if nsw decided 10.5t no boost was stock. I have a novak ss 10.5 stock spec havok setup in my basher/drifter car and I think its MORE FUN to drive then the boosted 17.5 I have to run for the two local clubs I race stock at. And its easily the same speed.

It'd be awesome to turn up to a track, fiddle with the fdr a bit and spend the rest of the time tweaking car setup and, you know, driving the bloody thing. Instead we have 6 different ways of achieving the same thing but all with their own side effects!

And whats the go with 27t brushed = 17.5 boosted? Last time I saw that on a track the 27s were almost as quick through the infield, but the second the straight comes into play and the boost kicks in the boosted cars will pull major distance on the 27s...

Anyway, rant over.
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Old 09-07-2011, 02:09 PM   #52
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I don't think those kv ratings are accurate and sensorless motors are not well suited for on-road racing. I don't understand why you would want this.
not referring to sensor-less motors just the way motors are rated. kv just makes more sense IMO.

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+1 as the kv ratings are all over the place... I know of some motors being 2200kv and 1900kv and they are both 17.5 turn.
Its how the manufacturers test and make the motor as it is. Then send it away to be tested by the governing body for approval so they are saying it is equal with all the other motors they have seen.
That's pretty much my point. Not all 17.5 have equal rpm per volt rating and not all motors are rated in "turns" anymore. kv is an actual measurement and just makes more sense than "turns", at least to me. So using your example, R.O.A.R. approved 1900kv - 2200kv would replace R.O.A.R. approved 17.5. My point is that it would be much easier to go have ONE motor rating instead of two.
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Old 09-07-2011, 02:44 PM   #53
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As far as I'm aware, the only 1/10 scale motors that only have a kv rating, are sensorless motors.

My old duo3 21.5 motor was rated at 2100kv. I can guarantee you that a 17.5 with the exact same kv rating would be much faster.

2 motors with the same number of windings are closer to one another than 2 motors with the same kv rating. kv ratings seem to be like battery C ratings, generally a completely worthless number.
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Old 09-07-2011, 03:00 PM   #54
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KV is just a measure of unloaded RPM. It's meaningless on the track.

POWER is what matters... but you'll never be able to scrutineer according to power (for various reasons), so the restricted construction rules work.

All the legal stock motors are very similar in internal construction, the biggest differences are in the timing advance (which should have been locked in the first draft of the rules, just like the brushed motors they replaced).
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Old 09-07-2011, 04:31 PM   #55
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KV is just a measure of unloaded RPM. It's meaningless on the track.

POWER is what matters... but you'll never be able to scrutineer according to power (for various reasons), so the restricted construction rules work.

All the legal stock motors are very similar in internal construction, the biggest differences are in the timing advance (which should have been locked in the first draft of the rules, just like the brushed motors they replaced).
I understand the reasoning for a "turns" rating. Just saying on a personal level a scientific measurement would be preferable. In that way I would know exactly the performance of the motor I was buying. kv might not be the proper measurement to use but something based on maths would make more sense to me.
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Old 09-08-2011, 01:30 AM   #56
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each manufacturer has their own testing system so the kv rating that they say it the kv x volts = rpm.
But now you have to work out as the battery pack starts at 8.4volts (for a 2 cell lipo) and slowly declines so then you need a dyno to work out a percentage of how your battery works and how efficient your system is.... Also you have to work out a exactly your endbell timing and the timing in the esc and work out what a degree of timing on both units equals in rpm aswell and add it to your findings.
Sorry to say thats all different too... But you will need a dyno to work that out aswell. Then you you need to know how your car performs on the track not just on the bench with a dyno (datalogger) and well look if your racing for dollars go right ahead.

Two many variables to list for a scientific result. Sorry to burst ppls bubbles.


You want a scientific way of doing it or just a base line work it out how everyone says

Nominal voltage x kv = rpm unloaded.

Good luck with it all
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Old 09-08-2011, 01:55 AM   #57
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Originally Posted by jjfo80 View Post
each manufacturer has their own testing system so the kv rating that they say it the kv x volts = rpm.
But now you have to work out as the battery pack starts at 8.4volts (for a 2 cell lipo) and slowly declines so then you need a dyno to work out a percentage of how your battery works and how efficient your system is.... Also you have to work out a exactly your endbell timing and the timing in the esc and work out what a degree of timing on both units equals in rpm aswell and add it to your findings.
Sorry to say thats all different too... But you will need a dyno to work that out aswell. Then you you need to know how your car performs on the track not just on the bench with a dyno (datalogger) and well look if your racing for dollars go right ahead.

Two many variables to list for a scientific result. Sorry to burst ppls bubbles.


You want a scientific way of doing it or just a base line work it out how everyone says

Nominal voltage x kv = rpm unloaded.

Good luck with it all
Fordy
Thanks for the insight Fordy.

Back to Stock class...

To Spec Tire or Not to Spec Tire for STOCK class? EDIT: for carpet track.
I for one am all for Spec tires in "Stock" type classes. A Spec tire will only make the class more competitive right. Spec or "Blinky" ESC, Advanced Timing motors, open LiPo and Spec Tires. Sounds like a good Stock class to me. For those that want to have any option of gear, MOD.
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Last edited by BrodieMan; 09-09-2011 at 02:43 AM.
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Old 09-08-2011, 03:51 AM   #58
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I would really like to see stock being a spec motor, FDR and spec tyres. It would come down to driver and car setup IMO.
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Old 09-08-2011, 04:11 AM   #59
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With spec tires, they work for championships just fine.

But for club racing, it is another thing to tech for every race which takes the fun away.

Where I (club) race, we allow foam or rubber tyre, any compound.... BUT. The the track is so high grip anyway that the only tyres that do not give grip roll are hard compound foams with minimal additive.

Various members of the club have tried many types of tires, foam,rubber,hard,soft compounds - and none of them were as quick as 40shore upwards foam tyre.

So, in a way we have a "spec" tyre, as nothing else will make you competitive

Spec tires DO help bring the racing closer, but not everyone wants to be limited to what tyres they are allowed to use.

It is something that may work for one community of racers, but not others.

Another negative point about spec tyres is that the newcomer to your track has another item to put on their shopping list, which is not always welcomed with open arms....
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Old 09-09-2011, 02:42 AM   #60
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With spec tires, they work for championships just fine.

But for club racing, it is another thing to tech for every race which takes the fun away.

Where I (club) race, we allow foam or rubber tyre, any compound.... BUT. The the track is so high grip anyway that the only tyres that do not give grip roll are hard compound foams with minimal additive.

Various members of the club have tried many types of tires, foam,rubber,hard,soft compounds - and none of them were as quick as 40shore upwards foam tyre.

So, in a way we have a "spec" tyre, as nothing else will make you competitive

Spec tires DO help bring the racing closer, but not everyone wants to be limited to what tyres they are allowed to use.

It is something that may work for one community of racers, but not others.

Another negative point about spec tyres is that the newcomer to your track has another item to put on their shopping list, which is not always welcomed with open arms....
Probably should have mentioned I was referring to carpet Stock class with Spec tires. Too much variation in track conditions on asphalt from race to race for a Spec tire to be used so I agree with your comments in that respect.

I don't see a spec tire being much of a problem for newcomers if the Race Director allows them to use what tires they have and when they need to buy new tires, go with the approved Spec tire.

To make it easier to tech Spec Tires at my club, I'm marking the tires with nail polish but in my case I have access to all the tires before they are sold.
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