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Old 07-23-2013, 12:23 PM   #16
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So basically your idea is completely pointless. It's either a class for beginners that is uncontrollable, or a class for experienced racers that is futile.
Maybe, maybe not. Look, I don't like all these limit or spec or breakout or whatever ideas either, I say just run mod or boosted and be done with it. Unfortunately many racers don't see it this way so they keep throwing crazy ideas out there that either wont work or aren't practical. I think this idea addresses many of those concerns but I could be wrong. If you have some actual constructive criticism to offer instead of just dismissing it out of hand, please feel free to do so. None of this is currently possible anyway since as far as I know, no esc exists that can do all of this so it's not like I'm trying to force it down your throat.
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Old 07-23-2013, 12:58 PM   #17
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Maybe, maybe not. Look, I don't like all these limit or spec or breakout or whatever ideas either, I say just run mod or boosted and be done with it. Unfortunately many racers don't see it this way so they keep throwing crazy ideas out there that either wont work or aren't practical. I think this idea addresses many of those concerns but I could be wrong. If you have some actual constructive criticism to offer instead of just dismissing it out of hand, please feel free to do so. None of this is currently possible anyway since as far as I know, no esc exists that can do all of this so it's not like I'm trying to force it down your throat.
Sure, my constructive criticism is that we have a class structure available to us already that works. TC has a variety of motors available to it from "easy for your granny" to "world class only". The onus is on racers and organisers to support the class that best suits them. The cars are built for 2s so why change, and motor classes need basically no scrutineering whereas rpm classes need constant scrutineering.

You will always have people that will spend silly money on having the fastest "slow" car, it doesn't mean that stock classes are a failure - if it bothers you just race in a class that has more power than traction, that is where driving skill matters rather than the depth of your pockets.
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Old 07-23-2013, 01:11 PM   #18
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As mentioned in the PM it is not only the topspeed but the needed time to reach the (limited) speed determing the laptime because we are accelerating from corner to corner. With this the lower turns motors have the advance still giviing a lot of stress on the drivetrain and tires.

There is a German company who devellopped a capacity meter and can be programmed to a certain capacity. Every driver has to be sure he is driving within the determed capacity. If he is going beyond it a red light will be shown. In that case you are working on the energy so basicly pushing with slow motors and save driving with fast motors using the same amount of energy equals the performance.
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Old 07-23-2013, 01:13 PM   #19
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Sure, my constructive criticism is that we have a class structure available to us already that works. TC has a variety of motors available to it from "easy for your granny" to "world class only". The onus is on racers and organisers to support the class that best suits them. The cars are built for 2s so why change, and motor classes need basically no scrutineering whereas rpm classes need constant scrutineering.

You will always have people that will spend silly money on having the fastest "slow" car, it doesn't mean that stock classes are a failure - if it bothers you just race in a class that has more power than traction, that is where driving skill matters rather than the depth of your pockets.
Thank you. That's pretty much exactly what I would say if I wasn't trying to come up with something to please those that disagree with us

I still think this is worth at least consideration though.
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Old 07-23-2013, 03:31 PM   #20
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So without discussing the merits of the class idea, what I'm intrigued by is how to accomplish RPM limits.

Measuring no-load peak RPM at the rim is dumb, IMO. It takes time in tech, and the car will always see much higher RPM on a stand in tech than it does on the track. It seems more interesting to me to have a physical device that can be controlled.

The most obvious would be something in-line with the sensor. What could you accomplish with that? Some things that would seem possible:
1) Monitor not just absolute RPM, but also delta RPM, so you limit both top speed as well as acceleration.
2) Completely cut the sensor signal to cut power, if the ESC cooperates.
3) Retard the signal to the speedo to effectively reduce motor timing and limit power when nearing limits?
4) Massively offset the signal to make the ESC actually apply brake? I'm not sure why you'd need this, though. And it'd probably be a really good way to burn down motors and ESCs.
5) Record telemetry for post-race inspection.

EDIT: Also, you could change the shape of the signal to maybe get the ESC to fire each phase for less time, as another way of reducing power without cutting it?

-Mike
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Old 07-23-2013, 06:20 PM   #21
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Originally Posted by sosidge View Post
Sure, my constructive criticism is that we have a class structure available to us already that works. TC has a variety of motors available to it from "easy for your granny" to "world class only". The onus is on racers and organisers to support the class that best suits them. The cars are built for 2s so why change, and motor classes need basically no scrutineering whereas rpm classes need constant scrutineering.

You will always have people that will spend silly money on having the fastest "slow" car, it doesn't mean that stock classes are a failure - if it bothers you just race in a class that has more power than traction, that is where driving skill matters rather than the depth of your pockets.
+1 well said.
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Old 07-23-2013, 07:54 PM   #22
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Originally Posted by grippgoat View Post
It seems more interesting to me to have a physical device that can be controlled.

The most obvious would be something in-line with the sensor. What could you accomplish with that? Some things that would seem possible:
1) Monitor not just absolute RPM, but also delta RPM, so you limit both top speed as well as acceleration.
2) Completely cut the sensor signal to cut power, if the ESC cooperates.
3) Retard the signal to the speedo to effectively reduce motor timing and limit power when nearing limits?
4) Massively offset the signal to make the ESC actually apply brake? I'm not sure why you'd need this, though. And it'd probably be a really good way to burn down motors and ESCs.
5) Record telemetry for post-race inspection.

EDIT: Also, you could change the shape of the signal to maybe get the ESC to fire each phase for less time, as another way of reducing power without cutting it?

-Mike
This is an interesting idea that the local track owner and I have already discussed.

For proper control, a microprocessor would need to monitor (but not modify) at least one of the sensor signals to read the motor speed, but have the capability to intercept the signal going from the receiver to the ESC. When the speed limit is reached, then the microprocessor would replace the normal signal from the receiver with a signal that gives neutral (zero) throttle. (I have an external LiPo cutoff module that works like this.)

The microprocessor could also monitor and control acceleration in this manner, as you already observed.

It's very much like real F1 cars used several years ago for traction control (monitor wheel speed, interrupt spark if necessary).
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Old 07-23-2013, 07:59 PM   #23
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So basically your idea is completely pointless. It's either a class for beginners that is uncontrollable, or a class for experienced racers that is futile.
This post may have come off as being a bit rough around the edges, but I completely agree. In a nutshell, I'm afraid that is exactly what the result would be. Everybody would end up running high power mod motors that go from zero to top speed in 15 feet, and I just don't see that being entertaining, fun or competitive.
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Old 07-23-2013, 08:09 PM   #24
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@Wingracer

What you propose requires a technical solution to implement it and one does not currently exist. You could achieve the same outcome by using a fixed FDR, but doing that makes teching a headache because the bean counters need to count teeth to ensure compliance.

So ultimately, what you are trying to achieve is a limit to wheel speed, this is currently done via blinky esc's and motor turn limits. But it could also be just as easily done by specifying a maximum wheel speed per class.

Teck then becomes a simple matter checking the motor is of the correct wind for the class and then putting a car onto a dyno and spinning it up to max rpm after ensuring the radio is set to 100% throttle. You could tech a car in 1 min, if they failed, all they have to do is change pinion or spur and come back and tech again.

For this, a technical solution already exists in the McPappy Dyno and Eagle Tree data logging software.

There are other benefits to doing this also, you could use a lower wind of motor and not have to push the thing to the point of magic smoke being released. Cooler running motors mean motors last longer and do not need to be replaced, fans become obsolete as you do not need to run the motor beyond its capabilities to remain compeditive.
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Old 07-23-2013, 08:44 PM   #25
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Stop the whining guys, and practice.....just sayin... These types of ideas have no chance whatsoever, and the will to make everything equal is a fantasy, not reality.... If you want equality, then only race VRC PRO....
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Old 07-23-2013, 09:22 PM   #26
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This is the answer. Old school hand out motors. Just like the big races used to have.

Can't time it. Timing is locked.

Can't rotor tune. The rotor is marked.

Just do the best with what you got.

If a group or orginization buys enough of them, you may be able to get them at a pretty good price.

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Old 07-23-2013, 10:06 PM   #27
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This is the answer. Old school hand out motors. Just like the big races used to have.

Can't time it. Timing is locked.

Can't rotor tune. The rotor is marked.

Just do the best with what you got.

If a group or orginization buys enough of them, you may be able to get them at a pretty good price.

Handouts solve nothing, you have the same old issues of someone whinging someone else got a better one than he did or people handing them back in again and again until they find one that is better than the rest as happened at a resent meeting that used handouts.
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Old 07-23-2013, 10:59 PM   #28
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Racing is inherently unfair, that's why we try like hell to make the unfair in our direction.
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Old 07-24-2013, 07:15 AM   #29
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So how would this work with a pan car?

Car "A" is running 42mm diameter tires.
Car "B" is running 44mm diameter tires.

With the same max RPM and the same gear ratio, Car "B" will still be faster due to the difference in rollout. There's also a variance in the diameter of different touring car tires, but since spec tires are often the norm with touring, that issue isn't really a concern there.
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Old 07-24-2013, 08:15 AM   #30
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I hate these threads.
.........me too......breakout racing is not racing.........lets penalize every racer who wins.....better yet give each racer his own class...then everyone can win their "A" main every time they go to the track......these ideas are ridiculous...
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