Change Up Gear Ratio/Wheel Speed

Alright so I am having a hard time deciding how fast I should make our robot go this year and I know that this is very important for this year’s game and it does not need to be too fast where the motors heat up and stop working and also make it undrivable and also does not need to be very slow where it takes forever and waste time. So what gear ratio yall recommend this year or seems to work well for this game?

The equivalent of 200-300 RPM on a 4" tank drive is ideal in my opinion. For example, a 200 RPM X-Drive, a 257 RPM tank drive, and just a regular 200 RPM tank drive would all be good candidates.

I’m personally going with a 257 RPM tank drive. 600 RPM motor with a 7:3 gear ratio.


I feel like a 200 RPM this year would be to slow so a 257RPM good or 300? What you going to do

So why you using the 600 RPM motor instead of 3:7 ratio and 200RPM gear cartage so the motor has more power

I’m currently using 333.33 RPM (5:3 200 RPM) on 3.25 inch Omni’s and it functions quite well. It’s a happy medium between speedy and defensive.

Me watching this with a 466 rpm tank drive (7:3 200 rpm) on 4 inch Omnis



tha’s fast. can u even control it??? i have 300rpm mecanums.

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Haven’t tested it out yet because I’m still building the final design but It was so fast the robot flipped over.

We are going for 5:3 200RPM on 3.25" wheels (270rpm in 4" standards) with a bot at about 14 pounds.

I kinda wanna ask other ppl who have the same rpm, how long can your robot drive before burning out


3:7 on a 200 RPM cartridge is 466 RPM, which is WAY too fast, and also has very little torque. 7:3 on a 600 RPM cartridge is 257 RPM, and while being around 25% faster than a normal 200 RPM drive, it only has to sacrifice about 25% of its torque.


5:3 is fine on 3.35 in. I believe it runs at 333 rpm. I run this setup and my drive doesn’t really wear out at all. However, your mileage may vary based on how you build it. Also, how did you get that 270 rpm number? Just curious really.

200*(5/3)*(3.25/4) = 270.83

We use a 200 RPM X-Drive, which comes out to about 283 RPM.

Ah yea that is a good point I just was worried about how a blue cartridge could sacrifice the power the motored outputted but I think we could make it up with the gear ratio either way, anyway what kinda of tires you going to be using. I feel like we need to be low to the ground.

Also I don’t wanna sacrifice much torque so this seems to be a good number because we need some defense power and when going up against a full defense bot we still can do something but for the most part we can just out run them.

you’re never going to be able to control that lol. it might not burn out if you have good build quality and never play defense/get defended, but chances are it will. 333 rpm is probably the most you’d ever possibly want on 4" wheels.

I agree with this, you seems to be moving way to fast and your torque is gone and your motors are now at risk of burning out and I can tell you that is so annoying.

I’ll prob use a 100 rpm motor but if not what gear ratio would you recommend for a tank drive 4 inch omnis.

anywhere between 200 rpm to 300 rpm is a good bet. the better you are a driving, the higher you should push it. if you’re not very good at driving though any speeds above 200 rpm aren’t really going to help you that much.

200 rpm 7:5 is a good speedy ratio for 4" wheels (equates to 280 rpm)
100 rpm 7:3 is good ratio for a slower drive (equates to 233 rpm)
but if you’re newer, 200 rpm direct drive is still pretty good, and is the easiest and most reliable setup you can have.