Spleen Hammer wrote:Hey all,
Some more questions here.
If I were to get a brushless setup would I have to get a metal spur gear? I've heard of brushless rig chewing threw spur gears like tasty snacks. If this was the case, where would I buy one?
No need to get a metal spur gear, there seems to be this "brushless fear" on here and tamiya club, a brushless is only as powerful as what you buy, its like blanketing all brushed motors as low power, its simply not true, i can get a sedate 27 turn brushed or a high power 7 or 8 turn brushed motor
Spleen Hammer wrote:
Also, is low turns better on motors or is high turns? What is a "turn"?
A turn refers to how many "winds" of wire there are, in sensored brushless, its always listed as having a ".5" at the end and instead of the winds being around the armature like on a brushed motor, in a brushless, the winds are in the can. Like brushed motors, the lower the number of winds, the faster the motor goes, eg, 13.5 is faster than a 17.5. its hard to give exact equivalents but a 21.5 is close to a 540 motor speed, 17.5 is close to a 27 turn stock motor and so on lower down the range, for reference, in general the fastest motor you would put in a 4wd buggy for racing would be 7.5, maybe 6.5, and in a 2wd, the fastest would probably be an 8.5. it should be noted that even though the motors can be put next to a brushed equivalent, brushed and brushless achieve speed rather differently, brushless produce more torque but less rpm so a brushless motor will always be geared taller than its brushed equivalent, which means the brushless will have a lower FDR to do the same speed as a brushed. i think a good fun motor is around the 13.5, enough motor for a bit of fun, not too much motor to the point where you break things etc,
Spleen Hammer wrote:
Lastly, how does one figure out gear ratios? Right now I have a 91 tooth spur gear and a 23t pinion gear (included in the kit for the dirt-tuned motor, which I have installed.) Does a smaller pinion equate to more speed or a larger pinion?
You know, is there a website where all of this is explained? Cause that'd be swell!
Thanks,
Spleen Hammer
Gear ratios are usually compared using FDR (final drive ratio), the calc is Spur, divided by pinion times by the internal ratio of your car, in your case its 91/23*2.05 = 8.11 FDR. all you need to do is look on the web for gearing tips for whatever motor you're thinking of running. if your not racing, and you want to keep the motor happy, always go for a higher FDR than the recommended racing ratio, it will give u more run time and keep the motor cooler.
in simple terms, a larger pinion will give you more top speed, but.... if you go too crazy on the gear ratio, the motor wont have enough power to push the car to its max speed and it will go slower and you will heat the motor up very quickly. a larger pinion will also accelerate slower and give you less runtime