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Old 11-09-2018, 03:16 PM
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Default Gearing VS timming question

I have non spec esc, with my current gearing and max timming im precisely same speed as my race mates (that are running spec elec), however im experiencing less runtime and more heat.

if i decrease my timming and increase gearing ratio and aim for the same speed will that cool things down and increase my runtime? Or do both actions cancel out? And hence i shouldnt bother?
i dont wana go through the trouble and hassle of experimenting till i reach the current same exact speed, if both actions cancel out or if there will hardly be any difference...

Knowing that:
Higher timming= more motor rpm, less runtime, and more heat
Higher gearing= faster car, less runtime, and more heat

my main goal is more runtime, and hopfuly less heat, (I read that lower timming runs the motor more efficiently)

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Old 11-09-2018, 03:47 PM
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Personally I would try reducing the timing just slightly (.5 to 1 degree) until you get the desired temperature and your lap times don't decrease dramatically at the end of the race. Then I would up my gearing if I'm out of sync with others lap times. All of this of course assumes you are driving exactly the same as your peers and everything else is equal, like car efficiency, starting battery voltage, etc. Good luck.
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Old 11-09-2018, 06:13 PM
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Share your motor setup, but it is best to set your timing according to no load amp draw(4A to 6A) on an analyzer first, then gear to the track(gear for infield punch)....Higher gearing does not necessarily make your car faster around the track......
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Old 11-09-2018, 08:15 PM
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Im not realy concerned with having it best suited for track or improving laptimes, i just want to remain same high speed on the straightaway...

its a tamiya tt01 which i have to take the rear end off if i want to swap spur gears which im not fond of
I guess ill zero out the timming first and see where that leaves me...


im using the ezrun B1 combo which has 13T motor that isnt even a true 3650 motor. Spec is justock 13.5T

Last edited by b3master; 11-09-2018 at 08:32 PM.
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Old 11-09-2018, 09:51 PM
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Originally Posted by b3master View Post
if i decrease my timming and increase gearing ratio and aim for the same speed will that cool things down and increase my runtime? Or do both actions cancel out? And hence i shouldnt bother?i dont wana go through the trouble and hassle of experimenting till i reach the current same exact speed, if both actions cancel out or if there will hardly be any difference...
thanks for the help guys, but my reason for starting this thread is to avoid the hassle of changing gears and avoid experimenting with timming if all Im doing is cancelling out at the end.... im after 30-40 practice as runtime

Does lower gear with higher timming cancel out the change in runtime with respect to higher gearing with a lower timming (acheiving same top speed)

Last edited by b3master; 11-09-2018 at 10:03 PM.
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Old 11-09-2018, 10:23 PM
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If you do not want to complicate things, then, after setting up the car with the least amount of rear toe in(0.5* if possible)+ no front toe out, go down on timing first(2* down at a time) with the same gearing:
#1) If you gain speed down the straight, then check temps to see if you get down to 120* or under. Keep taking 2* of timing off until you either stop gaining speed on the straight or your temps get to around 120*. That should be max performance for the weight of the car, and the only way to be faster is to lose vehicle/drivetrain weight...
#2) If you lose speed down the straight, then I would put the timing back to the initial max setting and gear lower, one tooth smaller on the pinion at a time, until I find the gearing where the temps fall down to 120* without losing much straightaway speed, but if you get the correct temps at a gear that makes you lose too much straight speed, then you will need to change the timing per step #1...
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Old 11-10-2018, 12:45 AM
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Originally Posted by bertrandsv87 View Post
Share your motor setup, but it is best to set your timing according to no load amp draw(4A to 6A) on an analyzer first, then gear to the track(gear for infield punch)....Higher gearing does not necessarily make your car faster around the track......
Whatever you do, don't follow this advice.
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Old 11-10-2018, 12:49 AM
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Originally Posted by b3master View Post
Im not realy concerned with having it best suited for track or improving laptimes, i just want to remain same high speed on the straightaway...

its a tamiya tt01 which i have to take the rear end off if i want to swap spur gears which im not fond of
I guess ill zero out the timming first and see where that leaves me...


im using the ezrun B1 combo which has 13T motor that isnt even a true 3650 motor. Spec is justock 13.5T
The ezrun combo you run is a sensorless system, and only supports around 26 degrees timing. You're not using too much timing even with it maxed out. The bigger issue is that you're using a completely different system to everyone else, so the temps aren't comparable.

What cars are the others using? The TT01 is not known for its efficiency.
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Old 11-10-2018, 05:14 AM
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Forget the temps, its not much of an issue. Its not an issue at all.
I just wana see yalls thoughts if the above cancel out so that i dont waste time changing gearing and experimenting timmings.....
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Old 11-10-2018, 05:53 AM
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Originally Posted by b3master View Post
Forget the temps, its not much of an issue. Its not an issue at all.
I just wana see yalls thoughts if the above cancel out so that i dont waste time changing gearing and experimenting timmings.....
ah, but so many post about how they enjoy working and testing almost more then like actual driving.
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Old 11-10-2018, 06:21 AM
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Originally Posted by b3master View Post
Forget the temps, its not much of an issue. Its not an issue at all.
I just wana see yalls thoughts if the above cancel out so that i dont waste time changing gearing and experimenting timmings.....
With the ezrun system you're wasting your time experimenting with timing. Just set it to max. Like I said before, it only goes up to 26 degrees. Most people run their sensored systems at around 40+ degrees.
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Old 11-10-2018, 06:42 AM
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Wow, either im not clear enough or ppl dont read what the question is and only the title

ill try to clarify

i dont want to reach optimum speed
i dont want to reach optimum temp

i dont care for either speed or temp

my concern is i dont want other racers nagging and complaining that im faster since im not running limited spec electrics, im running 13t they running 13.5t they run zero fixed timming, i can play with my timming

lower temp would seem to be a benifited byproduct of running less timming but it is NOT my concern

i want practice runtime, i want batts to last longer...

so, ill try again, and repeat the question, if i lower timming BUT lower the gear ratio (higher gearing, more top end), will they CANCEL OUT????
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Old 11-10-2018, 06:52 AM
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Literally my monster energy drink just shot out of my nose
Originally Posted by bertrandsv87 View Post
If you do not want to complicate things, then, after setting up the car with the least amount of rear toe in(0.5* if possible)+ no front toe out, go down on timing first(2* down at a time) with the same gearing:
#1) If you gain speed down the straight, then check temps to see if you get down to 120* or under. Keep taking 2* of timing off until you either stop gaining speed on the straight or your temps get to around 120*. That should be max performance for the weight of the car, and the only way to be faster is to lose vehicle/drivetrain weight...
#2) If you lose speed down the straight, then I would put the timing back to the initial max setting and gear lower, one tooth smaller on the pinion at a time, until I find the gearing where the temps fall down to 120* without losing much straightaway speed, but if you get the correct temps at a gear that makes you lose too much straight speed, then you will need to change the timing per step #1...
​​​​​​
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Old 11-10-2018, 09:44 AM
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Originally Posted by b3master View Post
Wow, either im not clear enough or ppl dont read what the question is and only the title

ill try to clarify

i dont want to reach optimum speed
i dont want to reach optimum temp

i dont care for either speed or temp

my concern is i dont want other racers nagging and complaining that im faster since im not running limited spec electrics, im running 13t they running 13.5t they run zero fixed timming, i can play with my timming

lower temp would seem to be a benifited byproduct of running less timming but it is NOT my concern

i want practice runtime, i want batts to last longer...

so, ill try again, and repeat the question, if i lower timming BUT lower the gear ratio (higher gearing, more top end), will they CANCEL OUT????
To answer your question. Yes and no...
For any given timing there is an rpm range that the motor operates at optimal efficiency. They higher the timing, the higher that rpm range is. Generally the more load you put on a motor (lower fdr) will decrease the maximum rpm that the motor is capable of for a constant voltage. So at first glass they (timing and gearing) look inversely proportional. However, you need to find the "sweet spot" first. It could be you need more timing and more gear.
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Old 11-10-2018, 09:59 AM
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Originally Posted by trilerian View Post
To answer your question. Yes and no...
For any given timing there is an rpm range that the motor operates at optimal efficiency. They higher the timing, the higher that rpm range is. Generally the more load you put on a motor (lower fdr) will decrease the maximum rpm that the motor is capable of for a constant voltage. So at first glass they (timing and gearing) look inversely proportional. However, you need to find the "sweet spot" first. It could be you need more timing and more gear.
My main problem is im not suposed to go faster, if my top speed is 40mph i need to stay 40mph, before justock spec racers complain about my speed! Im after more runtime...
however i can deduce from your post that i need to find out at the currect setting how efficient my current setup is, and to find this out i need to do as per somone's previous post and test my temps, if they too hot it means im running inefficiently, ill have to reduce timming till their stabelized then change gearing to get back to 40mph. however if the temps are good then i should just leave evrything the way it is , since its running effeciently wrt itself, nothing else i do will add runtime....


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