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Old 01-05-2015, 08:10 PM   #1
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Default Rev Limiters - The Next Step for Spec Racing?

http://www.gforce-hobby.jp/products/G0130.html

I noticed G-Force has included Rev Limiters in their lineup of products. It's interesting to see a few companies bringing in these into production.

Do you think they'll take off?
Will this improve spec racing? Closer racing?
Will it make racing more "spec?"
Would you consider using it? Why? Why not?

Share your thoughts.
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Old 01-05-2015, 08:20 PM   #2
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Default Rev limiting

This could be a step in the right direction for open racing without brakeout we will try them all you would have to do is pick out a tire size and gear on it and go unless it's like the old motor where Amps run away from the field I'm not sure about brushlessmotor yet. Concept is nice though
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Old 01-05-2015, 08:21 PM   #3
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I like the thought of sealed motors for spec racing. I would imagine it being much easier to control.
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Old 01-05-2015, 08:25 PM   #4
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Default sealed motor's

I have seen them run but it really did not seem like they where thst close toghter but I was not running one so it's hard to judge it but I like this rev limiters that would really let you run any motor if that's how they work it's going to be interesting to see
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Old 01-05-2015, 08:32 PM   #5
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For club racing... It's another part to fail, another part to fit into your amateur wiring job, another expense for new racers, or racers on a shoestring budget. And at that level, it's all setup and driving skill anyways. But if the club decided to give them a shot, I wouldn't complain, and would be curious to see the results.

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Old 01-05-2015, 08:43 PM   #6
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Originally Posted by Emaculant View Post
I like the thought of sealed motors for spec racing. I would imagine it being much easier to control.
Sealed motors won't help much. Take 10 motors off the production line and test each one, they'll all be completely different with one ultimately being the fastest.

But if you limit the revs you would have to limit the amps too. TORQUE WARS! lol

Couldn't all of this be done in the speedo anyways? Seems like that is where blinky should be in the first place
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Old 01-05-2015, 08:43 PM   #7
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Waste of time for spec racing unless you are going full throttle all the time around the track, yes it limits the top RPM, but it doesn't limit how fast you reach that RPM, therefore you'd still have a motor war, as you do already, you'd just be looking for a high torque motor rather than high RPM.
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Old 01-05-2015, 08:55 PM   #8
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More rules does not mean more parity. Fast guys will be fast almost no matter what.
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Old 01-05-2015, 09:37 PM   #9
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My 2cents.

A rev limit is the wrong direction IMO for an already highly regulated highly competitive spec class. More regulation means more issues for scruit and more ways to gain an advantage with better (often more expensive) equipment.

For those who will cheat more regulations opens the door for more ways to cheat.

The end result for the average racer is more costs and greater discrepancy in speed between the haves and have nots.

As it stands with blinky the motors that are already have heaps of low down grunt built for torque at the expense of rpm. If we limit rpm this will onky make the situation worse.

The current spec motors are not fast in terms of top speed but due to the instant power down low they are hard for lower skill drivers and beginners to control.

IMO we need sensible power restrictions with fewer regulations for restricted speed classes.

If we were to make any changes to the current regulations I would be heading in the direction of reduced down low power and increased rpm range.

When combined with higher FDR this would provide a more natural feel better brakes and place less thermal stress on the motor.

Perhaps the best way to achieve this is to spec a smaller diameter rotor such as 12.1mm instead of allowing the current high torque 12.5mm rotors.



Sealed motors, this wont work with sensored brushless motors as there is too much variation with sensor boards, which provides considerable performance miss match.

Last edited by DamianW; 01-05-2015 at 09:54 PM.
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Old 01-05-2015, 10:56 PM   #10
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My half though idea would be to have the 'Blinky' software limit both RPM and Amp draw maximums leaving tuning to finding the sweet spot with gearing and end bell timing.

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Old 01-06-2015, 12:34 AM   #11
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If there is going to be a rev limiter it should definitely be a part of the ESC software and not an extra part of electronics IMO.

That said, I don't think there is a real need for a rev limiter on big races like ETS because the speed of the cars is perfectly even (at least on the straight). And on club races there are other deciding factors like driving skill, setup, tires etc.
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Old 01-06-2015, 04:34 AM   #12
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Quote:
Originally Posted by DesertRat View Post
More rules does not mean more parity. Fast guys will be fast almost no matter what.
Come on now. What would RC be without a million and one excuses for not being competetive?
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Old 01-06-2015, 06:41 AM   #13
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Quote:
Originally Posted by B.C.Ninja View Post
Waste of time for spec racing unless you are going full throttle all the time around the track, yes it limits the top RPM, but it doesn't limit how fast you reach that RPM, therefore you'd still have a motor war, as you do already, you'd just be looking for a high torque motor rather than high RPM.
A rev limiter seems ideal in combination with a FDR but indeed the war on torque will start. Because our way of driving is more like accelerating from corner to corner the torque is important.

The current ETS stock motor/esc is very steady within specs. I know the guys who do check the cars and keep record of the KV numbers and all are very close. So far this has prooven to be a good setup.

A few years ago I did see a small piece of electronics devellopped by a German company you do need to mount between the battery and ESC. It did measure the used capacity and could be programmed by the race controll to a certain value. At the end of the race a LED did show if you have used the capacity within the limits or not. Some test did show good results.
This could be something to make racing equal with a free choice of motors and ESC's. A limited capacity makes a driver more carefull.
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Old 01-06-2015, 07:25 AM   #14
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If you're going to have a rev limiter/FDR rule, just make it open motor. If you want a 3.5 that revs up to the limiter instantly, have at it. Want something smoother and more controllable, you can do that too.
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Old 01-06-2015, 07:48 AM   #15
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Quote:
Originally Posted by Carnage9270 View Post
Sealed motors won't help much. Take 10 motors off the production line and test each one, they'll all be completely different with one ultimately being the fastest.

But if you limit the revs you would have to limit the amps too. TORQUE WARS! lol

Couldn't all of this be done in the speedo anyways? Seems like that is where blinky should be in the first place
Agreed! Limiting Amps for spec racing is the right way to control torque and acceleration. It's not the top speed that kills racing, it's the blistering speed the first 10 feet. To the new racer or beginner, it's hard to control the almighty throttle finger. They slide their car in and out of every corner until they learn to drive onroad. Besides as stated before, the acceleration rate is not natural. To a skilled driver this isn't an issue, so let's not make it one for mod classes.
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