f1n3sse
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It seems to me that brushless setups are in their infancy at the moment and it looks to like this technology will start to take off rapidly replacing a lot of nitro motors for racers and bashers alike. I took the liberty to do some research to understand for myself what exactly the low down is about brushless setups from motors, to lipos and escs. I just wanted some basic knowledge about the stuff and heres what I got soo far, anyone that owns brushless probably already knows all of this but those of us that don't here some good insight for you.
Motor Ratings - KV & RPM. brushless motors are given a KV rating, which is equivalent to RPM (rotations per minute) per volt; it lets you determine how fast that motor will rotate when supplied with a given voltage. with no load, a 2200Kv motor powered by a 4s LiPo pack (14.8 volts would spin at 2200x14.8=32,560 RPM. the current rating (C) specifies the maximum continuous and/or burst current that the motor is able to handle. generally to match a nitro engine, racers aim to keep their motor rpm within the range of 30,000 to 45,000. this enables lower end motors to run cooler. more expensive motors such as those by Neu and castle creations are more efficient and are rated to 60,000 rpm.
ESC and Motor selection you must choose a motor and ESC of the appropriate size for your RC. you wouldnt expect a 4 cylinder 1.5L engine to drive your dodge pickup, and neither will a v-10 diesel run in a civic. the larger diameter and longer motors are typically for larger vehicles. 70 to 80mm for 1/8 truggies and MTs. your desired Kv rating will depend on your supplied voltage but as a rule 2000 to 2700Kv = 4s LiPo pack, 1800 to 2200Kv = 5s LiPo. 1500 to 2000kv = 6s LiPo. most all manufacturers offer ESC and motor combinations for 1/8 conversions.
GEARING your motor and battery choices and the speed you want will determine the gearing of your build. one of hte best resources available for gearing is this website gearing guide. http://scriptasylum.com/rc_speed/ here you have hte options of entering all of hte vehices, voltage, motor, tire choice and desired speed, and it will compute the required pinion gear. most conversions run the pinion directly against the spur gear, which is fine as long as you use hardened pinions. be careful running too hot could ruin your motor, esc, and batteries. youll want to stay less than 170 degrees, this shouldnt be a problem if your geared appropriately.
Battery selection each cell has a nominal 9resting) voltage of 3.7 volts and a fully charged voltge of 4.2. a packs voltage is often expressed as the number of cells (S): 2S (7.4 volts), 3S (11.1) volts, 4S (14.8) volts ect.
-capacity normally measured in thousands of milliamp hours
-C rating refers to a packs maximum discharge rating, and its a multipe of its capacity, for example: a 25C 5000mAh pack could sustain 125 amps and a 20C 4000 mAh pack could sustain 80 amps.
-individual cells can also be linked in series with adapters to increase voltage or in parallel to increase capacity. example
-2x2S (7.4 volts 5000mAh wired in series is equivalent to 4s (14.8 volts 5000mAh
-2x2S 7.4 volts 5000 mah wired in paralel is equivalent to 2s2p (7.4 volts) 10,000mah.
I hope this article helped anyone who was looking for some baseline knowledge about the ever growing brushless industry.
all information was gathered from rc buggy and truggy magazine volume one 2009. I'm just the site noob 😀
Motor Ratings - KV & RPM. brushless motors are given a KV rating, which is equivalent to RPM (rotations per minute) per volt; it lets you determine how fast that motor will rotate when supplied with a given voltage. with no load, a 2200Kv motor powered by a 4s LiPo pack (14.8 volts would spin at 2200x14.8=32,560 RPM. the current rating (C) specifies the maximum continuous and/or burst current that the motor is able to handle. generally to match a nitro engine, racers aim to keep their motor rpm within the range of 30,000 to 45,000. this enables lower end motors to run cooler. more expensive motors such as those by Neu and castle creations are more efficient and are rated to 60,000 rpm.
ESC and Motor selection you must choose a motor and ESC of the appropriate size for your RC. you wouldnt expect a 4 cylinder 1.5L engine to drive your dodge pickup, and neither will a v-10 diesel run in a civic. the larger diameter and longer motors are typically for larger vehicles. 70 to 80mm for 1/8 truggies and MTs. your desired Kv rating will depend on your supplied voltage but as a rule 2000 to 2700Kv = 4s LiPo pack, 1800 to 2200Kv = 5s LiPo. 1500 to 2000kv = 6s LiPo. most all manufacturers offer ESC and motor combinations for 1/8 conversions.
GEARING your motor and battery choices and the speed you want will determine the gearing of your build. one of hte best resources available for gearing is this website gearing guide. http://scriptasylum.com/rc_speed/ here you have hte options of entering all of hte vehices, voltage, motor, tire choice and desired speed, and it will compute the required pinion gear. most conversions run the pinion directly against the spur gear, which is fine as long as you use hardened pinions. be careful running too hot could ruin your motor, esc, and batteries. youll want to stay less than 170 degrees, this shouldnt be a problem if your geared appropriately.
Battery selection each cell has a nominal 9resting) voltage of 3.7 volts and a fully charged voltge of 4.2. a packs voltage is often expressed as the number of cells (S): 2S (7.4 volts), 3S (11.1) volts, 4S (14.8) volts ect.
-capacity normally measured in thousands of milliamp hours
-C rating refers to a packs maximum discharge rating, and its a multipe of its capacity, for example: a 25C 5000mAh pack could sustain 125 amps and a 20C 4000 mAh pack could sustain 80 amps.
-individual cells can also be linked in series with adapters to increase voltage or in parallel to increase capacity. example
-2x2S (7.4 volts 5000mAh wired in series is equivalent to 4s (14.8 volts 5000mAh
-2x2S 7.4 volts 5000 mah wired in paralel is equivalent to 2s2p (7.4 volts) 10,000mah.
I hope this article helped anyone who was looking for some baseline knowledge about the ever growing brushless industry.
all information was gathered from rc buggy and truggy magazine volume one 2009. I'm just the site noob 😀
