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Motor timing and timing curves

Old 03-27-2022, 10:48 AM
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Default Motor timing and timing curves

Hi Guys.
As we know, and broadly speaking, to set up the timing on a Spec (Blinky mode) brushless motor, we'd normally tweak the mechanical timing to draw the optimum no-load current. So, say 6amps on a typical mid wind motor. Then we'd chase the gearing around until we got the car behaving as we want it without revisiting the motor timing.
I get that.
But let me just ask some of you tuners out there something about running with advance curves etc
Example: Say that through testing my optimal fixed timing is 50 degrees. I'd set the fixed timing at, say, 30 degrees. Then access the other 20 degrees of timing through advance + Turbo, whilst not exceeding the total timing of 50 degrees.

Does that sound right? or would you perhaps do it differently? Even though we can take the timing past optimal, is there any real reason to do that at high RPM? For example starting at the 30, adding 20 more through curves and maybe add another 10 on Turbo at the top end?

I realize that it also depends on the type of running you're doing, track, drag, off-road, on-road etc but is my basic concept of limiting the total timing to "optimal" sound or faulted?

Looking forward to your input.

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Old 03-27-2022, 11:09 AM
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Keep reading. It never ends. I learned the most from titpe ct cse putes sheets. It can get pretty wild. Have fun.
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Old 03-27-2022, 11:35 AM
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Oh just got what you mean. duh LOL They don't answer any of my questions though.

Last edited by MarcusKeeler; 03-27-2022 at 11:46 AM.
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Old 03-27-2022, 12:43 PM
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how do you have advance and turbo on blinky.. you dont. set endbell timing at 40+ and see how it runs,,,
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Old 03-27-2022, 02:04 PM
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So even if you set turbo above most efficient timing the motor will still use it and turn more rpm’s.
I set my end bell to most efficient then run the track for 5-10 minutes check temp.
If I feel the need for more and temp is good I do boost or turbo couple degrees
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Old 03-27-2022, 02:33 PM
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Originally Posted by the rc guy
how do you have advance and turbo on blinky.. you dont. set endbell timing at 40+ and see how it runs,,,
Thanks for chipping in Dude but you didn't read my question fully.
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Old 03-27-2022, 02:44 PM
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Originally Posted by Blackplastic
So even if you set turbo above most efficient timing the motor will still use it and turn more rpm’s.
I set my end bell to most efficient then run the track for 5-10 minutes check temp.
If I feel the need for more and temp is good I do boost or turbo couple degrees
Yep, I definitely see that. In your experience, does taking it 10degrees into inefficiency have any noticeable negative effect ?
My specific situation is No-Prep drag. So I don't really have issues with extra heat generation, it's more about maximizing performance at the big end whilst also being able to run lower timing for the hit & first half of the track.

I've heard guys chatting about manipulating timing and there is so much conflicting opinion out there it's hard to see through it. I think as a start point I'm going to go optimum timing minus 20. Then use the advance curve to get back up to optimum by half track without resorting to Turbo. The turbo option is an easy way of getting more timing into it at the big end without disturbing the advance curve if I feel I need more Jam.
So you reckon what, 5 degrees past optimum would be a reasonable number?
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Old 03-27-2022, 04:16 PM
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Originally Posted by MarcusKeeler
Thanks for chipping in Dude but you didn't read my question fully.
Your question explicitly mentioned tuning for blinky. You can't use those settings in blinky.
As we know, and broadly speaking, to set up the timing on a Spec (Blinky mode) brushless motor, we'd normally tweak the mechanical timing to draw the optimum no-load current. So, say 6amps on a typical mid wind motor.

That's actually a terrible way to tune a motor for blinky. The 6A setting worked for some motors before the short stack craze about 5-6 years ago. Many modern motors will cook at that setting.
Example: Say that through testing my optimal fixed timing is 50 degrees.
The optimal timing depends on RPM, as the magnetic field distorts.

Have a read of this: https://pphaneuf.github.io/rccars/ar...timing-theory/
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Old 03-27-2022, 05:05 PM
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i weed your question. you say blinky so the rest is a wish that aint gonna happen .and ill chip in anytime i want to.
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Old 03-27-2022, 05:12 PM
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Originally Posted by the rc guy
i weed your question. you say blinky so the rest is a wish that aint gonna happen .and ill chip in anytime i want to.
That's a shame that you have to be that way. I'm just a guy asking for help and support, I was being nice but I guess this is your playground and you're going to stomp around it like nobody else is welcome.
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Old 03-28-2022, 08:08 AM
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Originally Posted by MarcusKeeler
Hi Guys.
As we know, and broadly speaking, to set up the timing on a Spec (Blinky mode) brushless motor, we'd normally tweak the mechanical timing to draw the optimum no-load current. So, say 6amps on a typical mid wind motor. Then we'd chase the gearing around until we got the car behaving as we want it without revisiting the motor timing.
I get that.
But let me just ask some of you tuners out there something about running with advance curves etc
Example: Say that through testing my optimal fixed timing is 50 degrees. I'd set the fixed timing at, say, 30 degrees. Then access the other 20 degrees of timing through advance + Turbo, whilst not exceeding the total timing of 50 degrees.

Does that sound right? or would you perhaps do it differently? Even though we can take the timing past optimal, is there any real reason to do that at high RPM? For example starting at the 30, adding 20 more through curves and maybe add another 10 on Turbo at the top end?

I realize that it also depends on the type of running you're doing, track, drag, off-road, on-road etc but is my basic concept of limiting the total timing to "optimal" sound or faulted?

Looking forward to your input.

stay away from the 6 amp myth
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Old 03-28-2022, 10:20 AM
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6A is not a myth for certain brands of motors.

It's important to contact the manufacturer of a motor you plan to buy and find out what they recommend setting the amp draw first. If they can provide you the information you need, then proceed with buying their motor, otherwise continue searching for a brand of motor which is targeted for optimal stock racing performance.

Trinity recommends 5.6A
Tekin recommends 3.2A

I have no idea what other manufactures recommend but you can see these are 2 completely different ends of the spectrum!

It's also worth noting that setting current draw should be done after you've checked for the shim. This is done by checking the timing between the 3 phases, if any reading is farther than 2° away from another then you need to play with the spacing on the rotor with a shim pack, this is far more time consuming than most are willing to put the effort into but will certainly be worth the effort if you want max efficiency to maintain your punch toward the end of a main A perfectly shimmed motor will have identical timing readings across all 3 phases, I don't think I've ever had a single motor get all 3 but I usually get 2/3 the same with the 3rd only 1° off from the other 2.
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Old 03-28-2022, 01:24 PM
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Originally Posted by billdelong
6A is not a myth for certain brands of motors.

It's important to contact the manufacturer of a motor you plan to buy and find out what they recommend setting the amp draw first. If they can provide you the information you need, then proceed with buying their motor, otherwise continue searching for a brand of motor which is targeted for optimal stock racing performance.

Trinity recommends 5.6A
Tekin recommends 3.2A

I have no idea what other manufactures recommend but you can see these are 2 completely different ends of the spectrum!

It's also worth noting that setting current draw should be done after you've checked for the shim. This is done by checking the timing between the 3 phases, if any reading is farther than 2° away from another then you need to play with the spacing on the rotor with a shim pack, this is far more time consuming than most are willing to put the effort into but will certainly be worth the effort if you want max efficiency to maintain your punch toward the end of a main A perfectly shimmed motor will have identical timing readings across all 3 phases, I don't think I've ever had a single motor get all 3 but I usually get 2/3 the same with the 3rd only 1° off from the other 2.
it is a myth if it wasnt they wouldnt sell anything to check the timing it would be just amp meters, lol, my trinity revtech (using trinity motorlyzer)with 42degress timing (3.2 amps) has better kv's and lap times than set at 50 degrees(6amps) the motor at 6 amps may sound fast but is not as efficient . according to the lap counter my motor at 3.2 amps is alot faster than 6 amps
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Old 03-28-2022, 03:02 PM
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Originally Posted by Marcos.J
it is a myth if it wasnt they wouldnt sell anything to check the timing it would be just amp meters, lol, my trinity revtech (using trinity motorlyzer)with 42degress timing (3.2 amps) has better kv's and lap times than set at 50 degrees(6amps) the motor at 6 amps may sound fast but is not as efficient . according to the lap counter my motor at 3.2 amps is alot faster than 6 amps
You have a valid point, I should've referenced Trinity MonsterMax and newer as well as Tekin G3 and newer for the respective recommended current draw settings. RevTech's are older generation (standard stack?) motors so I can see how 3.2A would be better suited for back then. I believe most folks are talking about current generation stuff so we need to be careful when contacting the manufacturer to be sure we give them proper information about the motor and application... I'm also referring to off-road use and it's possible that on-road TC might peak at a different current setting.

It's also worth pointing out that the current draw settings will change over time as the magnet fades on the rotor, you might notice that it drops over time and you may need to increase the current draw back up to the recommended setting to accommodate the fade in the magnet which no doubt you've had to experience if you're still running a RevTech today, ha! I think Trinity has since released the X-Factor series, I have not tested this motor yet but I would imagine that Trinity has kept the same general recommendation for their current motors.

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Old 03-28-2022, 03:10 PM
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Originally Posted by billdelong
You have a valid point, I should've referenced Trinity MonsterMax and newer as well as Tekin G3 and newer for the respective recommended current draw settings. RevTech's are older generation (standard stack?) motors so I can see how 3.2A would be better suited for back then. I believe most folks are talking about current generation stuff so we need to be careful when contacting the manufacturer to be sure we give them proper information about the motor and application... I'm also referring to off-road use and it's possible that on-road TC might peak at a different current setting.

It's also worth pointing out that the current draw settings will change over time as the magnet fades on the rotor, you might notice that it drops over time and you may need to increase the current draw back up to the recommended setting to accommodate the fade in the magnet which no doubt you've had to experience if you're still running a RevTech today, ha! I think Trinity has since released the X-Factor series, I have not tested this motor yet but I would imagine that Trinity has kept the same general recommendation for their current motors.
I’m sure you could get away in off-road with higher timing and amp draw , my testing was on TC
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