V5 Flywheel Weight

Don’t cheat. It’s not worth it.

If you’re caught, there will be consequences. Sometimes this is a slap on the wrist (ex: Don’t do this again). Sometimes this is having to rebuild part/all of your robot. Sometimes this is even worse…

Maybe you’re not caught. Maybe you get away with it. Maybe cheating helps you win an event. After the initial happiness wears off, what do you have left? Knowing that you won an extracurricular robotics competition because you played by a different set of rules than your peers? For what? A trophy? Congratulations.


How does “trying to make a part that is identical to the VRC legal part” suddenly get labeled as “cheating” and “playing by different set of rules”?

Wasn’t the idea of using parts “from third party suppliers” that are “functionally identical to VRC legal parts from VEX” always essential to RECF philosophy of making VRC more affordable to wider population of students?


You can talk “philosophy” all you want, but the rules of R6 and R7 in the game manual (https://content.vexrobotics.com/docs/2022-2023/vrc-spin-up/VRC-SpinUp-GameManual-2.0.pdf) are all that matters in the end. R7 is very specific about third party parts, and machining and powder coating your own version is not included in R7.


If identical third party parts were allowed, it would open the floodgate for teams to argue that their non identical parts are close enough and then they have an advantage. It makes if far easier for almost everyone involved to just say no to everyone rather than yes to something with a minor difference from another. According to the inspection checklist:

official parts portion

ALL robot components are OFFICIAL VEX V5 components as sold on VEXrobotics.com or materials used as color filters, minimal grease or lubricant, minimal anti-static compound, hot glue for cable connections, unlimited rope (no thicker than 1⁄4”), rubber bands and zip ties that are identical to those included in the V5 product line, cable protection materials and tape for connections and labeling, and certain non-VEX screws, nuts and washers.

So unless it’s a non functional decoration, you don’t have a Robot until it passes inspection, per the manual, section 2, definitions. Competing without a legal Robot is cheating.


Where do you draw the line on what counts as “identical”?

1 Like

At the point where the part is so similar to something legal that someone could believably lie and say that it was made through a known-possible vex-legal process, the actual difference between the parts is meaningless, and there is no reason why it should be illegal at all.


Just going to point out that someone machining that part probably learned a lot more as part of the process than if they had just bought it from vex.
Edit- not encouraging cheating or saying I would do it, just pointing out something that should be important to a program designed to inspire people in stem and teach them.


Me: Not a Vex part, take it off.
VexTeam: Made of the same metal.
Me: Not a Vex part, take it off.
VexTeam: Powder coated.
Me: Not a Vex part, take it off.
VexTeam: Almost the same holes.
Me: Not a Vex part, take it off.
VexTeam: But we learned so much.
Me: Now you are learning some more things. Not allowed because of the rules. Until you take it off you can’t compete. And I’m going to ask the head ref to look at your robot before each match to make sure it doesn’t “accidentally” get put back on. Isn’t learning great?


I am troubled by this discussion. Clearly, some feel it ethically ok to violate Game Manual rules as long as they don’t get caught.

I would remind team members you are all supposed to be adhering to the RECF Code of Conduct for VRC. Perhaps re-reading it, or reading the for the first time, will help frame your responses in the future.


Because vex is a closed system. Same reason screwgate happened. You can’t make a part completely identical to vex and such a part might give a competitive advantage. If you want an open system, go do frc or ftc.


I am not saying you are wrong, I am saying that at the point at which this competition comes down to technical differences between identical parts, the rules have failed us far before any dishonest teams may have.


/sigh. So I tell people:

  1. Work with the rules and find your own workaround that is within the rules
  2. Get the rules changed
  3. Don’t play the game

You can work on getting the rules changed. Whining here about it is not going to accomplish that. You need to convince the GDC. To do that you need support from Coaches / Mentors. I’ve found that RECF and as an extension the GDC is much more favorable to listen to them. You also need to reach out to the Student Advisory Board and get them convinced and have them present it to RECF. Their voice is also pretty loud.

I was very forceful and really pushed screwgate. There was some support from the EP community, but for an overwhelming majority it was “Meh, not in my top 10 of issues”. You will do better with coaches/mentors since they are at a different rock face digging.

Or point 3, there are large number of FRC and FTC teams that would love to have your skill set, you would be a huge asset to them. It would be a loss to the VEX community, but it may make you (and others) much happier. Life is too short to do things when at the end of the day they aggravate you.


There’s a process for changing the rules. Disobeying the rules is not that process.


Did I say it was? I never said that breaking the rules of the game manual was okay, just that the existence of those rules is similarly not okay. These are not mutually exclusive.

1 Like

How do you prove this though? The GDC stated in screwgate that the difference of a couple of grams is enough to give the aluminum screw a competitive advantage. However you can’t take of people’s flywheel weight and weight them for accurate measurements. Even then, how do you know the weight isn’t more towards the outside of a custom flywheel weight giving it a higher moment of inertia to mass ratio? There is no way to make “identical” parts work without opening a massive can of worms.


While I find it similarly silly, I can understand the reasoning for the nylon screws thing. Steel screws weigh about 7 times as much as nylon screws, so over the course of a few hundred screws on a robot that’s a significant difference. A few grams difference on a part there are only one or two of (flywheel weight) is negligible.

If I was writing the rules, I’d leave it up to the teams to convince the inspectors that the part is functionally identical. If a reasonable person can see that it’s effectively the same, I don’t see why there should be an issue.


Then you get into situations where one inspector is convinced and another isn’t. Then the competitor complains about inconsistencies.


Then competitors would be smart to err on the side of caution, wouldn’t they?

1 Like

That would be smart. However, based on my experience as an inspector, does not always happen. So many basic mistakes, even with something as crystal clear as the 18inch sizing cube.


Listen, I’m ngl I hate banning things for unnecessary reasons. 3D printing should be allowed in VRC, I think that screw gate was the dumbest thing I’ve ever heard in my life, and painted pnuematics: what an episode. But it’s a very bad idea to have an environment where people can say “eh, we’ll make it on our own, because VEX sells it, and it’ll be close enough, even though it’s illegal”.

I think the only exception should be wires, but that’s only because being able to use your own wires and cables would benefit my robot greatly (slip ring connector I believe it’s called). I wouldn’t dare say “even though it’s illegal, I’ll use that wires anyways because it’ll be hidden in wire management”. and vex doesn’t even SELL these things, if they’re literally selling them there’s just no justification. I get it. Supply shortages are annoying. We have no flywheel inserts and are probably going to comp with a DIY insert (poly and traction wheel), despite how much I dislike it. But don’t cheat.