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Old 04-10-2017, 03:30 PM   #1
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Default Let's talk about timing....

I have a question, so I have been playing around with the timing on my Fantom 21.5T motor.

I have learned a lot on the forums about setting it to high has some serious amp draw, and you need a motor analyzer to find that sweet spot.

My question comes from a experiment I did over the race weekend.

Currently I have my Fanton set at 40 deg. I felt like it had more in it.

From what I understand you can increase the timing if you are seeing a difference, but not if you are not seeing a performance gain, and just adding heat.

So I turned the timing up to 45 deg and didn't really see much of a difference in temp or in speed.

Then I turned the timing up to 50 deg, and goodness did I see a difference. I saw a real difference, it was a absolute bullet.

My fear is I am pulling way to many amps though. After 4 mins it came off at 140 deg with a slight smell to it. Not burnt but a slight smell. I WANT to keep it at 50 deg for the speed boost, but I am concerned of over amping the motor. It does go up to 60 deg, but I am thinking that even 50 might not be safe.


What are my options here. If I can keep it cool is a little over amp ok? I really enjoyed the increase in power, but not if it cost me a good motor.

Any insight would be great.

Thanks.
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Old 04-10-2017, 03:45 PM   #2
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Quote:
Originally Posted by Metalsoft View Post
I have a question, so I have been playing around with the timing on my Fantom 21.5T motor.

I have learned a lot on the forums about setting it to high has some serious amp draw, and you need a motor analyzer to find that sweet spot.

My question comes from a experiment I did over the race weekend.

Currently I have my Fanton set at 40 deg. I felt like it had more in it.

From what I understand you can increase the timing if you are seeing a difference, but not if you are not seeing a performance gain, and just adding heat.

So I turned the timing up to 45 deg and didn't really see much of a difference in temp or in speed.

Then I turned the timing up to 50 deg, and goodness did I see a difference. I saw a real difference, it was a absolute bullet.

My fear is I am pulling way to many amps though. After 4 mins it came off at 140 deg with a slight smell to it. Not burnt but a slight smell. I WANT to keep it at 50 deg for the speed boost, but I am concerned of over amping the motor. It does go up to 60 deg, but I am thinking that even 50 might not be safe.


What are my options here. If I can keep it cool is a little over amp ok? I really enjoyed the increase in power, but not if it cost me a good motor.

Any insight would be great.

Thanks.
No higher than 6 amp draw
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Old 04-10-2017, 03:49 PM   #3
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No higher than 6 amp draw
So I am going to have to buy/ find someone with a motor analyzer for me to use.

The difference between 45 deg and 50 deg is SUBSTANTIAL.

I am guessing if it is not over 6 amp it is pretty dang close at 50 deg....

But it was so much faster......
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Old 04-10-2017, 04:17 PM   #4
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Anything over 6amps is just getting too much heat
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Old 04-10-2017, 04:25 PM   #5
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So I am going to have to buy/ find someone with a motor analyzer for me to use.

The difference between 45 deg and 50 deg is SUBSTANTIAL.

I am guessing if it is not over 6 amp it is pretty dang close at 50 deg....

But it was so much faster......
True my 21.5 is just a hair under the 50 degree mark and it's right at 6 amps geared at a 3.5 fdr at a large asphalt track (kraceway) came off the track about 135degrees and it was stupid fast!

I do have a R1 fan blowing on the motor.

You can buy a inexpensive amp meter and you can find the sweet spot if you look on you tube there is a video that shows you how
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Old 04-10-2017, 04:33 PM   #6
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Here it is

https://youtu.be/xLbnYJ3gJ-0
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Old 04-10-2017, 04:33 PM   #7
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Is there a way to check amp draw on a BL motor without using one of the motor analyzer boxes?
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Old 04-10-2017, 04:35 PM   #8
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No higher than 6 amp draw
My Maclan 25.5 has always drawn 7-8 amps at moderate timing, but come off the track cool, and never faded throughout the entire previous season.

I ultimately look at temps as the final indicator for how far i can advance my timing. If it's coming off the track under 160, then I'm totally happy with the performance.
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Old 04-10-2017, 04:36 PM   #9
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Is there a way to check amp draw on a BL motor without using one of the motor analyzer boxes?
Yes look at the above link
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Old 04-10-2017, 04:51 PM   #10
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My Maclan 25.5 has always drawn 7-8 amps at moderate timing, but come off the track cool, and never faded throughout the entire previous season.

I ultimately look at temps as the final indicator for how far i can advance my timing. If it's coming off the track under 160, then I'm totally happy with the performance.
Correct, amp draw isn't an indicator of heat. Some motors can handle the amp draw much better than others. That is directly proportional to the efficiency/cooling of the stator. Lot of factors go into that but simplifying it to how many amps are being drawn isn't the correct way by any means.
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Old 04-10-2017, 06:20 PM   #11
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Is there a way to check amp draw on a BL motor without using one of the motor analyzer boxes?
Yes, You can use a multimeter.
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Old 04-10-2017, 06:49 PM   #12
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Simple to use a multimeter, check your instructions for the correct setting but basically you connect the multimeter in series on the positive lead from your battery - into the multimeter COM terminal and out through the terminal labelled 10A or 20A. You want to test under no load so remove the motor or the pinion so it can spin freely. Then, of course, just turn on your esc and use your transmitter at full throttle to read the amp draw on the multimeter.
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Old 04-10-2017, 08:00 PM   #13
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Originally Posted by rcja View Post
Simple to use a multimeter, check your instructions for the correct setting but basically you connect the multimeter in series on the positive lead from your battery - into the multimeter COM terminal and out through the terminal labelled 10A or 20A. You want to test under no load so remove the motor or the pinion so it can spin freely. Then, of course, just turn on your esc and use your transmitter at full throttle to read the amp draw on the multimeter.
I'd recommend applying throttle gradually and keeping an eye on the current draw in case you overload the multimeter. If the timing is set too high it can exceed 10A, and even if set to draw 6A, it'll draw more than that initially from a dead stop.
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Old 04-11-2017, 05:56 AM   #14
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Originally Posted by Metalsoft View Post
I have a question, so I have been playing around with the timing on my Fantom 21.5T motor.

I have learned a lot on the forums about setting it to high has some serious amp draw, and you need a motor analyzer to find that sweet spot.

My question comes from a experiment I did over the race weekend.

Currently I have my Fantom set at 40 deg. I felt like it had more in it.

From what I understand you can increase the timing if you are seeing a difference, but not if you are not seeing a performance gain, and just adding heat.

So I turned the timing up to 45 deg and didn't really see much of a difference in temp or in speed.

Then I turned the timing up to 50 deg, and goodness did I see a difference. I saw a real difference, it was a absolute bullet.

My fear is I am pulling way to many amps though. After 4 mins it came off at 140 deg with a slight smell to it. Not burnt but a slight smell. I WANT to keep it at 50 deg for the speed boost, but I am concerned of over amping the motor. It does go up to 60 deg, but I am thinking that even 50 might not be safe.


What are my options here. If I can keep it cool is a little over amp ok? I really enjoyed the increase in power, but not if it cost me a good motor.

Any insight would be great.

Thanks.
You haven't said if it's a 'Torque' or 'Rev' version of the motor!

Did you try leaving the timing down and gearing up instead?
I think this 'set it for 6A' is a bit misleading.
Motors vary, even from the same batch from the same manufacturer. As you add timing you are reducing the efficiency, but what you need to find out is whether this reduction is coming out as a greater increase in heat over power (Power will go up, but as heat etc builds up the motor's internal resistance will also increase)

Don't forget, that as you increase the timing, you also lose torque. It's a balancing act, there is always a trade off somewhere.

At a recent test day (mid size outdoor asphalt) I changed from 13.5 boosted to blinky for some actual races, but forgot to change the motor timing up from 30deg (did change gearing and ESC).
The guy I was with also running Fantom, timing (over 50deg) and we had almost identical gearing. We were 0.18 apart on fastest laps, 0.12 on best 10 laps.
Realising what I'd done (or forgotten to do ) I put timing up to 45deg whilst we both kept the same gearing.
0.14 apart on fastest and 0.05 on best 10 laps.

Sadly I couldn't fit taller gearing without taking everything apart so couldn't be bothered, but it's certainly something I would try before adding a load of heat using timing.
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Last edited by Skiddins; 04-11-2017 at 06:20 AM.
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Old 04-11-2017, 06:03 AM   #15
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Originally Posted by JoshuaRC10 View Post
My Maclan 25.5 has always drawn 7-8 amps at moderate timing, but come off the track cool, and never faded throughout the entire previous season.

I ultimately look at temps as the final indicator for how far i can advance my timing. If it's coming off the track under 160, then I'm totally happy with the performance.
Probably due to the 25.5's having so little power.
In my F1 (21.5, so not much more powerful) I have max'd out the timing and can run almost any gearing I want and the motor temp doesn't vary much, usually 45-55degC, it just goes a bit slower when the gearing isn't in the sweet spot.
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Last edited by Skiddins; 04-11-2017 at 06:18 AM.
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