Boost Your RC Car's Speed: How to Master Motor Kv Optimization for Max Speed!

[@guitarzzero]

Where does pinion size factor in? Higher kv=smaller pinion, correct?

[@pbrod8325]

I have been banging a 6500kv 24xx size Surpass motor with a 10bl60 HW ESC on my 16889... run 3s Zeee at who knows what 'real' C... Ripped 63mph on her. Looking to get to 70 or 75. Ordered up yeeeeap a HW 2845 4700kv to run cooler and get cleaner runs. Hard to get the 16889 to stop wheeleying at WOT. Thanks for the videos really gets the numbers to come together!!! I

[@RCexplained]

Thanks for sharing. Good luck un getting to 70!

[@CSL33]

Thanks for these videos. This one probably being your most comprehensive one in regards to kv vs. max power determination? I had build a similar model in excel a few months ago, and except for HOW to account for load, my results were identical. The one variable that I also included, however, was the change in wheel diameter at different Final Drive RPMs. Unless you have solid rubber or high-end belted tires, it can make significant differences to top-end speeds (and load factors). 👍

[@Stoff-9001]

Thanks for making this man!

[@RCexplained]

My pleasure!

[@xzessperated]

Thanks so much for sharing your knowledge. I have bad eyesight. My goal speed is only 100 mph but because of my eyesight I need to get to this speed as quick as possible so I can still see the car and where it is on the road. Your information will help me do this I think. Wheel spin could become a problem over such a short distance. Maybe Raz's Perfect Pass system and some 1 million in the differentials could help but I can only experiment with those things.

[@RCexplained]

Yes, you will also want to make certain you have the most sticky tires for maximum acceleration potential. This will help keep distances shorter.

[@xzessperated]

@@RCexplained Thanks for that.

[@Chris-adams-rc-journey]

Large diameter motors are a little easier to control and have the torque you need for your goal. A castle 1717 wouldn't be a bad motor for you goal but a big tp motor would really do it. Goodluck to you and I hope you reach your goal

[@ChiefRickyRC]

Thank you for every great video 👍

[@RCexplained]

So nice of you

[@solomongathings7724]

Nice!! So a direct question. I have a 800 kv motor and an 1100kv motor, i want crazy speed, so i was thinking of going with the 800kv and gearing it 1:1. I figured the 800 could handle to more rather than the 1100kv. With 12s being the powersystem of the 800kv motor. So with that being said l, Would the 800kv be able to handle that kind of power better with less heat. I know there are so many more variables but mot looking for exact answers just a what would you go with if you had to pick between 800kv/max 5 or 1100/max5 for speed. And big gearing

[@RCexplained]

I would choose the motor that is rated for the most wattage. If there is no rating, I would select the motor that is physically the largest. Then optimize on power by selecting the maximum voltage without going over the max RPM of the motor. Using gearing that is appropriate for the power output of the motor. Example - Don't gear a 300watt motor for 100mph.

[@rowndo]

Still don't understand a thing. So if I change to a Higher Amps esc and a higher kv motor, my rig will still havethe same speed? and will be damaged? I'm so confused. I'm trying to upgrade my Team Associated 1/10 Hoonicorn. Which have a Reedy’s 550 15-turn brushed motor (can't find the kV) and a ESC of 80CAmps. I wan't to go faster and have a bit more torque to make it slide better on rubber tires.

[@RCexplained]

Hello, you have a brushed power system. Getting a brushless power system will make a world of a difference.

[@matusknives]

This is an excellent video, but even though I do understand that one can not easily deduce the amount of current being drawn under certain conditions, a discussion on that topic would help a lot because that could then be turned into heat production and also help to understand what batteries / ESC / motor combination to choose as to not damage any of the three components. My (naive!) understanding would be that ESC limits the maximal current it can provide to the motor. If that is the case one could maybe use that as a starting point when changing the motor. Or is that the wrong assumption? Thank you

[@RCexplained]

thanks for the comment Matus. Speaking about current draw is indeed difficult to do. The current draw would be very difficult to speak about considering RC Cars. There's so many factors that influence what the value would be. Not all ESC's are able to safely limit current draw.

[@josephcaruana9165]

Kindly I have a limitless with a max 6 esc and a 1650kv rocket motor wich it's maximum volts is 26v, and I am thinking of trying an 8s. I don't know if the esc the voltage, amps, or frequency to increase the motor speed because I think it should be safe if the voltage drops on load and the motor doesn't go 50,000rpm?

[@RCexplained]

Over spinning the motor is risky. If the car takes flight, the motor unloads and can exceed the maximum RPM you specified. In terms of current, you could easily gear down and from there monitor temps. If temps are OK move up in pinion size.

[@josephcaruana9165]

Kindly what is kt and how it is measured?

[@RCexplained]

Check this out, does this help?: kzbin.info/www/bejne/rpqam6t_oL1lrLs

[@reallythough4591]

I'm working on a monster truck speed project. Truck is in range of 14lbs. Running a 2050kv motor and spectrum 6s ESC. My goal is 150mph, just to see if it can be done on stock system. I ran 69.9 today on just better than 1 to 1 gearing from pinion to spur, and 43 teeth on front and rear diffs. First pass, I tried to gun it as I passed camera, and tires ripped free I'm aware now that I should have let system cool between runs. On immediate second run, I was guilty of the same transgression passing the camera, and the ESC cut out at half throttle at 69.9. I'm thinking I need a longer run up, and more gradual, consistent trigger pull. Any recommendations?

[@Chris-adams-rc-journey]

160 amp spektrum esc struggles to get past 100 even in a light 1\8 gt car. You are gonna need an xlx2 for it to even be possible in a speed car. Monster truck tires aren't gonna make it past 70 to 80mph. Gonna have to work around those 2 issues to have a chance

[@reallythough4591]

@@Chris-adams-rc-journey I'm running rear felony hoons all around, and have swapped the diffs to twin rear felony diffs with straight cut input shafts. At 69.9 Sunday, I ripped tires free, and got excited passing the camera, and just yanked the trigger, instead of gradual to keep amps down. I realized that I turned gain back up after trials before Sunday, and servo was too fast. I took 9 teeth out of gearing, and dropped to 4s to figure out waggle. Felt like an idiot when I thought to look at remote after first run. Problem went away immediately. I'm trying to see what the top end is of the spectrum system. I've got a max 5 waiting in the cupboard, but I'm gonna try and get this 14lbs monster to 120. I'm not very experienced at rc, but love numbers. I need a really long run up, and some patience. I'll post a vid soon. It's a ton of fun trying to get this thing to do something it definitely wasn't designed to do. Thanks for the insights.

[@Chris-adams-rc-journey]

Be slow and smooth on the trigger and also heat your batteries up. Heat them to 115⁰ish and the internal resistance of the lipo will dron about 50٪ and help with voltage sag and voltage recovery good luck buddy I'd love to see you meet yor goal

[@reallythough4591]

@@Chris-adams-rc-journey thanks brother. I got a buddy that has to win at everything, and he got me into it. Just can't take the constant rubbing my face in it. Good guy, but the ego needs to be taken down a few spots. That's why I picked the fireteam. Perfect sleeper, especially if I don't try and trick it out. I went out for a hoonicorn after Ken block died, and they gave me a deal on the fireteam. When I told him, he asked me to go to rc store, and he got two hoonicorns, and a Felony. And now it's, you'll never beat my felony or super slash, so here I am, attempting the nearly impossible on stock system. But hey, at least I'm not at the bar wasting money on over priced drinks.

[@tabaharif3606]

is it different explanation if I swap KV brushless motor on RC boat?

[@paulclancy2404]

Boat motors are little bit bigger same principle just you don't have gearing

[@ohannes939]

So lower kv motors can turn bigger pinions. As bigger can motors have low kv.

[@RCexplained]

Larger motors will naturally have more torque/power.

[@ohannes939]

@@RCexplained so for a kraton 8s. Stock motor 4685 1250kv or 5687 1100kv. The bigger can motor with bigger pinion and smaller spur should have more top speed?

[@ArmanRC]

lower kv =more torque ,less speed.. thanks for sharing

[@paulclancy2404]

Everyone over gears over volts or add too much rotation mass so I think why people prefer lower kv motors

[@ChiefRickyRC]

4s and under id say anywhere 4000kv-7000kv. 5s and higher id stay under 3000kv

[@scottm2398]

If youre going for a higher kv motor to get more speed , but then you gear down with the higher kv motor to get a similar speed to what you originally had then what's the point of changing the motor at all? Lol

[@RCexplained]

It's best to start conservatively checking temps before adjusting gearing for max performance.

[@fabriziodaurizio1009]

Yeah nah. The amp rating is the Max current draw at Max load, eg: acceleration. The quicker a motor spins the less it draws. The power you worked out (amps X volts = watts) is the power consumption, it has nothing to do with the output of the motor but more so on how it is built. You are, however, correct with the rest.

[@ChiefRickyRC]

If anyone wonders how im so smart i learned here