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Old 12-12-2016, 06:53 PM   #241
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Hence the reasoning behind the choice of a 17.5 motor for the GT class, at moderate gearing, & fixed timing, it's around the same speed as a non fixed fdr 21.5, maybe even a little slower, but it ensures motor longevity, so people are not "temping" their motor to see how far they can push it on any given day, or track.
Even so, 4.5 is still way too conservative on those 21.5 motors. It was chosen specifically to be slower for the juniors.
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Old 12-13-2016, 06:00 AM   #242
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You're right about not knowing the power/torque curve etc. However at no load there's essentially no torque, so most of the current pretty much translates to heat. It'll only get worse under load. I think it's mainly used to find the upper bound of timing before efficiency goes out the window, rather than finding peak power.
Yes and no. Under no load there isn't much opposition to overcome hence not much heat created. Only under load it does matter how much heat is created because only then it tells you something.

Advancing the timing beyond reason creates heat at no load because the motor has to overcome its own inefficiency. That doesn't mean anything. It only tells you where the timing is totally inefficient. That however does not mean it is a safe limit on the track. The safe limit could be far from it and it's going to vary from track to track.

In the days of brushed motors, we used to adjust timing by rotating the brush carrier with the motor under power whilst monitoring revs. Once the revs started to drop you knew you were past peak power.
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Old 12-13-2016, 06:19 AM   #243
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Yes and no. Under no load there isn't much opposition to overcome hence not much heat created.
This part I disagree with. When you're pumping 6 amps at 8.4V under no load, that's roughly 50W of power being consumed. But since it's doing no work, it's mostly dissipated as heat. Simple conservation of energy. My motor got pretty hot pretty quick with those tests at those currents.
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Old 12-13-2016, 07:15 AM   #244
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This part I disagree with. When you're pumping 6 amps at 8.4V under no load, that's roughly 50W of power being consumed. But since it's doing no work, it's mostly dissipated as heat. Simple conservation of energy. My motor got pretty hot pretty quick with those tests at those currents.
Read to the end of my post.
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Old 12-13-2016, 02:56 PM   #245
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Read to the end of my post.
I did, and don't disagree with your other comments. I disagree with your assertion that high amps under no load generates little heat since it's not pushing anything.
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Old 12-13-2016, 04:52 PM   #246
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I tried running a car at Bayswater at FDR of 4.5 (we usually run 3.0 as it's a large outdoor track) the motor was revving it's box off 5 meters into a 80 meter straight and after 5 mins came off at 85c and that's with a WTF 30mm fan sitting on it. (Test motor was a Sky RC Ares 21.5 with timing set at 0 endbell)

Let it cool and an hour later ran the same motor on the same track at FDR 3.0, lap times were 2 seconds a lap better and the motor came off at a happy 55c

Undergearing a motor can do just as much damage as overgearing it, and that's something that seems to have been forgotten by those trying to cram a control motor and controlled FDR down our throats.
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Old 12-13-2016, 05:12 PM   #247
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I tried running a car at Bayswater at FDR of 4.5 (we usually run 3.0 as it's a large outdoor track) the motor was revving it's box off 5 meters into a 80 meter straight and after 5 mins came off at 85c and that's with a WTF 30mm fan sitting on it. (Test motor was a Sky RC Ares 21.5 with timing set at 0 endbell)

Let it cool and an hour later ran the same motor on the same track at FDR 3.0, lap times were 2 seconds a lap better and the motor came off at a happy 55c

Undergearing a motor can do just as much damage as overgearing it, and that's something that seems to have been forgotten by those trying to cram a control motor and controlled FDR down our throats.
I wouldn't say they're trying to cram anything, they've taken several polls and the majority seem to be leaning towards a control motor. And now it's up for vote, and if the vote doesn't pass, they're not going to force the issue.
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Old 12-13-2016, 05:28 PM   #248
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Based on the nature of the responses when I offered a dissenting opinion in the appropriate chat page and on facebook as well as communications made by some to myself by PM and to the club where I race regarding me having the audacity to argue against said changes, I would respectfully disagree with you on that gigaplex. That said, yes, it's down to the club vote, which many have done, but I suspect if it doesn't get through it will continue to resurface albeit in some amended format until they push it through.

It has however illustrated to me a very ugly side to the hobby which we don't all see, where a lot of club politics, brand affiliations, loyalties to brands/sponsors etc lead to threats and bullying over what should be such a fun sport. I would advise anyone wanting to have an opinion to be aware of those behind the scenes pulling the strings, as they can turn what should be an honest opinion on a thread like this, into an excuse to attack on a more personal level (which should NEVER happen, nor should bullying of any kind in any situation by any person)
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Old 12-13-2016, 07:01 PM   #249
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I wouldn't say they're trying to cram anything, they've taken several polls and the majority seem to be leaning towards a control motor. And now it's up for vote, and if the vote doesn't pass, they're not going to force the issue.
At first I was for it, but then against it as it seemed to be something rushed through before the end of the year.
Also there was no information about the selected motors at all, no brand, no model, no data on the testing, no information about what fdr would be used at each given track.

When I voiced my concerns, I was used as an analogy, and lectured that the hand out motor proposals was aimed at racers like me.

Yes, I am a "budget" racer, but I still say a handout motor (21.5) won't make any difference when you have other racers using $800 chassis's (yes plural) and an Ogio bag full of gear, including multiple body shell's to be used as a "tuning aid", various speed controls, the latest batteries, and enough option/spare parts to open their own hobby store.

As for polls showing that a majority want handout motors, the polls were badly wrong at the recent US election.
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Old 12-13-2016, 07:45 PM   #250
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At first I was for it, but then against it as it seemed to be something rushed through before the end of the year.
Also there was no information about the selected motors at all, no brand, no model, no data on the testing, no information about what fdr would be used at each given track.

When I voiced my concerns, I was used as an analogy, and lectured that the hand out motor proposals was aimed at racers like me.

Yes, I am a "budget" racer, but I still say a handout motor (21.5) won't make any difference when you have other racers using $800 chassis's (yes plural) and an Ogio bag full of gear, including multiple body shell's to be used as a "tuning aid", various speed controls, the latest batteries, and enough option/spare parts to open their own hobby store.

As for polls showing that a majority want handout motors, the polls were badly wrong at the recent US election.
Precisely, the way that people who dared to query the proposals and ask for more details were responded to was confronting and to be honest quite disturbing.
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Old 12-13-2016, 07:56 PM   #251
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Actually I think there are 2 things that will cause the vote to fail, first I think is the people on the ground feel there hasn't been enough testing/information the second is no direction for what clubs run their own club during club days.

Yes the theory is that controlled motor/FDR would eventually flow through, but than you end up with a disparity within the class for those running the combo and those that not, because the reality is as soon as you go to a controlled FDR you are already running slower unless the motor wind changes.

I don't think this vote will pass, but time will tell.
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Old 12-13-2016, 08:51 PM   #252
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Actually I think there are 2 things that will cause the vote to fail, first I think is the people on the ground feel there hasn't been enough testing/information the second is no direction for what clubs run their own club during club days.
Spot on. The "word" I got from the racers was that there wasn't enough transparency in regards to which motors would be used, how they would be tested, both in a car, and on which type of motor checker/dyno.

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Yes the theory is that controlled motor/FDR would eventually flow through, but than you end up with a disparity within the class for those running the combo and those that not, because the reality is as soon as you go to a controlled FDR you are already running slower unless the motor wind changes.

I don't think this vote will pass, but time will tell.
And that's another problem, it's alright to say "the clubs can decide what format to run" on club days.
With that you'll have some racers wanting to race with the same motor as the control motor, and you'll have some that want to race with their motor of choice.

And as for the question will 21.5 be the new "stock"? Over here it seems to be the new "stock", and 13.5 being "super stock".
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Old 12-13-2016, 09:32 PM   #253
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I tried running a car at Bayswater at FDR of 4.5 (we usually run 3.0 as it's a large outdoor track) the motor was revving it's box off 5 meters into a 80 meter straight and after 5 mins came off at 85c and that's with a WTF 30mm fan sitting on it. (Test motor was a Sky RC Ares 21.5 with timing set at 0 endbell)

Let it cool and an hour later ran the same motor on the same track at FDR 3.0, lap times were 2 seconds a lap better and the motor came off at a happy 55c

Undergearing a motor can do just as much damage as overgearing it, and that's something that seems to have been forgotten by those trying to cram a control motor and controlled FDR down our throats.
Where did you get those numbers from? Our straight is about 45-50 meters depending how generous you are with your measurement.

Yeah, undergearing can do damage, but nobody is suggesting undergearing or overgearing as a rule.

You can find any number of flaws in the rules, forgetting they are there only to create a level playing field, not to cook your motor. You have to realise people have more common sense than that.
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Last edited by niznai; 12-13-2016 at 09:43 PM.
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Old 12-13-2016, 09:55 PM   #254
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At first I was for it, but then against it as it seemed to be something rushed through before the end of the year.
Also there was no information about the selected motors at all, no brand, no model, no data on the testing, no information about what fdr would be used at each given track.

When I voiced my concerns, I was used as an analogy, and lectured that the hand out motor proposals was aimed at racers like me.

Yes, I am a "budget" racer, but I still say a handout motor (21.5) won't make any difference when you have other racers using $800 chassis's (yes plural) and an Ogio bag full of gear, including multiple body shell's to be used as a "tuning aid", various speed controls, the latest batteries, and enough option/spare parts to open their own hobby store.

As for polls showing that a majority want handout motors, the polls were badly wrong at the recent US election.
That was because we in Oz have a small market and such things take large numbers to get the interest from a manufacturer with the capacity to run the order.

To do the leg work and contact a manufacturer, get some motors and start testing before we even knew if the racers want to go this way, just doesn't make sense in the real world, that is why we had to vote on an idea, not an airtight contract. Unfortunately, a lot of people used this an excuse to vote the idea down.

Not knowing what motor to run, it would have been completely stupid to come up with a FDR, the more so since like Nexxus said, different tracks will demand different FDRs to stay within reason.

These are just propositions aimed at trying to level the playing field, implementation is another thing.

I don't find any of these good enough reasons to turn down the idea, but it was voted down in our club, unfortunately.
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Old 12-13-2016, 09:57 PM   #255
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Spot on. The "word" I got from the racers was that there wasn't enough transparency in regards to which motors would be used, how they would be tested, both in a car, and on which type of motor checker/dyno.
To be honest, I find this disappointing. Paraphrased, they're saying "we can't fix every known & perceived problem, so we'll fix none of them".

This is clearly a contemporary discussion for Aussie racers, but similar issues are cropping up all around the world.

Wallet racing/motor wars are real - putting some controls in place will help. There are other issues to work on, but let's start somewhere.

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