4LikesFan or no
03-12-2019, 09:52 AM
#2
to me and it's just my opinion I would say it all depends on you and how you do stuff. I personally do not but I gear modestly I do not crank the timing up on my motors, and I charge my batteries at a normal rate. Now there are several of the faster guys at my track the do run fans BUT they charge their batteries at a higher rate to get more punch, they crank the timing and gear to the moon so they need it. so like I said it all depends on how you do certain things, and possibly where you race could effect it also.
03-12-2019, 10:44 AM
#3
Tech Apprentice
i run fans on my ST and 4wd buggy both are 13.5 but not on my 17.5 2wd buggy
i have never ran mod but from what ive been told no one runs a fan in mod but not sure why
i have never ran mod but from what ive been told no one runs a fan in mod but not sure why
03-12-2019, 11:20 AM
#5
1/8th or 1/10th scale? I have never used a fan on any 1/8th buggy. 1/10th I use them on 17.5 stock builds because I crank the timing and they run hot. Mod buggy, it just depends.
03-12-2019, 12:05 PM
#6
I run a fan with my stock buggy (Tekin Spec R 17.5) but I also dont push things very hard. I charge at a modest 1c and am not pushing timing like some at my track (Guy at the track suggested 55 degrees of timing and I am at like 45 or 48 so backed off slightly) and am currently even geared down atm (if I remember right I am at 75 spur 25 pinion atm. Many currently running 26/27 on current layout. I was I initially 26 but liked the extra acceleration in a couple spots; I'm going 5o test 27 next time I can run). I've just always liked keeping various electronics cool and even on PC builds have included extra unnecessary fans because why not
03-12-2019, 12:21 PM
#7
Kind of depends on your circumstances. If you want to race and keep up with the fastest guys, then you’ll need a fan for your motor because you’ll be able to gear it and time it more aggressively. I run one for that reason but I wish there was a way to mount a fan without it looking so tacky :/
03-12-2019, 12:36 PM
#8
Tech Master
remember motor fan.. speed controller fan...
I run mod... 10.5... geared easy... no fans at all..
but monitor temperatures... motor and controller....I have never reached 120 degrees "F"... even in 90 degree outside races..
I run mod... 10.5... geared easy... no fans at all..
but monitor temperatures... motor and controller....I have never reached 120 degrees "F"... even in 90 degree outside races..
03-12-2019, 12:52 PM
#9
fan on esc. fan on motor when I can. put holes in body's not really for cooling but to limit my ballooning parachuting .catching air ..
03-12-2019, 01:18 PM
#11
No fan at all. Even on 4x4 mod buggy. Even geared and boosted to the moon. Piddly short mains and q's don't heat the motor up much when the only straight is hardly 4 seconds long including the sweeper leading onto it.
Fans cost a fraction of a rotor. But I've had a few get damaged. I'm just going to let the rotor roast, and replace it as needed, with the motor bearings. If the motor isn't completely obsolete by then.
Fans cost a fraction of a rotor. But I've had a few get damaged. I'm just going to let the rotor roast, and replace it as needed, with the motor bearings. If the motor isn't completely obsolete by then.
03-12-2019, 01:20 PM
#12
03-13-2019, 08:04 PM
#14
Tech Master
If the motor spends most of its time in the continuous torque limit of the motor you can get up to 30 percent more continuous torque. This assumes you are at or want to find the continuous torque limit of the motor. If the motor spends more time in peak (accelerations) which is always above continuous a fan wont help unless the average of peak and continuous is under or at the continuous limit.
here is a simplification. If you have a motor that can deliver 200 watts continuously by natural convection you can add another 60 watts to the limit of the motor with a fan.
if half the race is accelerating at 300 watts and half the race is 100 watts you dont need a fan. If accelerating you average 301 watts and 100 watts continuously you need a fan. 101 and 300,,,you need a fan. Timing and gearing are used to move the motor efficiency to the average rpm the track needs. A fan moves the continuous efficiency north by about 20-30 percent at sea level but not exceeding 10,000 feet. At 10,000 feet and up you need a fan to retain sea level continuous torque.
here is a simplification. If you have a motor that can deliver 200 watts continuously by natural convection you can add another 60 watts to the limit of the motor with a fan.
if half the race is accelerating at 300 watts and half the race is 100 watts you dont need a fan. If accelerating you average 301 watts and 100 watts continuously you need a fan. 101 and 300,,,you need a fan. Timing and gearing are used to move the motor efficiency to the average rpm the track needs. A fan moves the continuous efficiency north by about 20-30 percent at sea level but not exceeding 10,000 feet. At 10,000 feet and up you need a fan to retain sea level continuous torque.
Last edited by Bry195; 03-14-2019 at 06:45 PM.
03-14-2019, 05:54 AM
#15
Always run a fan, the magnetic strength of a neodymium magnet decreases with temperature and can be permanently lost if the temperature is too high. Also the resistance of the windings will increase slightly when they are hot. Cold motors always perform better and last longer.