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Old 12-25-2009, 09:31 AM   #1
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Default About brushless motor timing.....

i am fairly now to the concept of electric racing and is still abit confused about brushless motor timing effects...

my questions:

advancing timing boosts rpm obviously but does overall power increase, ie torque also increase? or you loose torque at the expense of rpm? it seems to me that advancing timing gives me more power overall...

i was also told gearing up, ie smaller gear ratios, has the same effect as advancing motor timing... is this true? if so, how do you gain more power by just gearing up? or do you loose torque?

do you guys adjust the mechanical timing on your motors? if so, why do you do so since most esc have timing shift functions.... if gearing up has the same effect, why not just gear up?
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Old 12-25-2009, 10:15 AM   #2
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Quote:
Originally Posted by katze View Post
i am fairly now to the concept of electric racing and is still abit confused about brushless motor timing effects...

my questions:

advancing timing boosts rpm obviously but does overall power increase, ie torque also increase? or you loose torque at the expense of rpm? it seems to me that advancing timing gives me more power overall...

i was also told gearing up, ie smaller gear ratios, has the same effect as advancing motor timing... is this true? if so, how do you gain more power by just gearing up? or do you loose torque?

do you guys adjust the mechanical timing on your motors? if so, why do you do so since most esc have timing shift functions.... if gearing up has the same effect, why not just gear up?

All good questions...

Advancing timing increases RPM but decreases torque. So when you do that you must gear differently. Gearing can also give you more top end speed similar to adding timing, but it does not increase timing. The ESC's that add timing do so when the motor has less load on it. With less load on the motor, less torque is needed and adding timing becomes beneficial. Also another advantage is that you can keep the timing lower on your motor and gear for infield speed. But on faster portions of the track the ESC will add timing and give you the top end that you need, making your car faster overall. Before all of these timing advances you had to gear for the best overall performance...now you can have the best of both worlds and not sacrifice speed on one part of the track over the other.


There is a much more detailed answer to this but I hope this gives you an idea...
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Old 12-25-2009, 11:29 AM   #3
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Quote:
Originally Posted by katze View Post
i am fairly now to the concept of electric racing and is still abit confused about brushless motor timing effects...

my questions:
...
do you guys adjust the mechanical timing on your motors? if so, why do you do so since most esc have timing shift functions.... if gearing up has the same effect, why not just gear up?

I have advanced the time on my motor for other reasons too. In my Pro10 (10.5 2S Pancar), when coming out of the corners, to much torque is hard to control. So by advancing the timing on the motor, it makes the car more controlable. When the RPM and Power come on, the car is generating more downforce so it has the traction to take the power. The power band also feels more linear with the motor timed this way.

One thing about the timing though, the further you get from zero, the less efficient the motor becomes, so it will generate more heat, and use more Mah from your battery.

Shawn.
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Old 12-25-2009, 01:13 PM   #4
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would advancing the timing only work on sensored brushless motors??

I cant see how it would work on unsensored, as the esc wouldnt know the reference point to know where 0deg would be ??
My unsensored esc does however allow for timing to be advanced
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Old 12-25-2009, 01:39 PM   #5
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I would say motor timing is best used when gearing options are limited. Some motor mounts have only so much room to support the spur and pinion gears. So, you either go down in gears, or advance timing, though the motor. Some guys will also use it to give them a little more speed.
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Old 12-25-2009, 04:52 PM   #6
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would advancing the timing only work on sensored brushless motors??

I cant see how it would work on unsensored, as the esc wouldnt know the reference point to know where 0deg would be ??
My unsensored esc does however allow for timing to be advanced
You can adjust timing on the esc, not on the motor itself. Sensored motors have adjustable timing via a dial on the endbell.
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Old 12-25-2009, 06:54 PM   #7
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did some googling and read the castle mamba brushless tuning guide....

can anyone explain why brushless motors have unlimited torque?... in theory it does but real life? after reading the article, it seems to me that i do not need to worry abt infield torque as long as i have good batteries.... so i can gear say 5.5 vs 5.0 FDR and i will not be able to feel the torque difference with brushless?
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Old 12-25-2009, 07:16 PM   #8
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They are one and the same. You cannot make rpm without also making torque. Torque is what spins the shaft. To increase increase motor rpm, you must increase torque at the top of the rpm range. When doing this, you must also sacrafice torque at the bottom end. This means, increasing max rpm in turn REDUCES BOTTOME END TORQUE. More rpm at the expense of punch. This also increases heat.

In the end I'm guessing overall power is the same. But due to the difference in power deliver, either setting has it's place on different tracks.
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Old 12-26-2009, 12:10 AM   #9
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Originally Posted by trerc View Post
You can adjust timing on the esc, not on the motor itself....
Ive seen the option for this on my esc, cant quite get to grip with how it would work
To advance the timing , wouldnt the esc need to know where the rotor is ???
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Old 12-26-2009, 03:33 AM   #10
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Quote:
Originally Posted by 1101 View Post
Ive seen the option for this on my esc, cant quite get to grip with how it would work
To advance the timing , wouldnt the esc need to know where the rotor is ???
On sensoreless motors it does sense where the rotor is by some kind of back feed through the 3 motor wires.
On sensored motors it has a sensor board that helps control/check timing at standstill and slow speeds.
Sensoreless has its benefits at rpm and sensored at very slow rpms hence why most new generation esc's are hybrid combinations of the two.
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Old 05-20-2010, 09:44 AM   #11
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Default novak ex13.5 help

i got the 13.5 ex ,added big bearing and endbell with sintered rotor,
my problem still wak compared to other 13.5 such as the ss,could it be the timming

help please
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Old 12-07-2012, 02:26 PM   #12
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timing is basically how much degrees of advance can be applied to your motor, usually low timing is for high KV motors, in my understanding
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