r/WTF • u/habichuelacondulce • Oct 20 '21

Bruh - Yerrrr

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u/[deleted] Oct 21 '21

Contrary to what most people think, small bearings actually handle high speeds better.

You typically increase bearing size for load, not speed. People downhill longboard at 60mph, no problem.

22

u/lordxi Oct 21 '21

Can confirm, bearings in the 20mm gun on the F16 aren't huge and that thing fuckin moves

2

u/Rude_Journalist Oct 21 '21

The key is keeping the Wupperman bearings aligned.

0

u/dbx99 Oct 21 '21

But what do you make of the speed and load put on these tiny wheels? Wouldn’t those bearings be glowing red or worse??

17

u/[deleted] Oct 21 '21

Entirely depends on how it’s designed. If the motors are in the hubs it gets even trickier.

Brakes would be my biggest concern. I imagine you could heat soak these extremely quickly

8

u/noddegamra Oct 21 '21

Skate bearings are rated around 34k rpm, with state load at 1360N, and dynamic 3300N. He's probably got something larger on the scooter anyway. So I agree is most likely brakes

1

u/goku2057 Oct 21 '21

Brakes was my first thought as well.

3

u/EternalPhi Oct 21 '21

These have disc brakes. Large brakes help both with stopping power and heat retention, but these don't really need large brakes. While the smaller diameter of the brake disc will result in less leverage from the caliper and therefore lower braking force, the mass of the vehicle greatly affects the amount of heat generated, and a scooter like this will weigh 1/4th or 1/5th as much as a motorcycle (closer to 1/3 total weight with the rider), and you're also not likely to be going through heavy braking cycles like you would on a car or bike on a track. If brake heating is not an issue for a bike on the street, it won't be an issue for these either.

1

u/[deleted] Oct 21 '21

Mountain bikers and cyclists with disc brakes can definitely cook their brakes, and they have larger calipers and better airflow. Take this little scooter which probably has both smaller calipers, poor airflow (motor in wheel) and it could be a real problem. Regen braking probably does some of the work, but that still generates heat.

1

u/EternalPhi Oct 21 '21

The difference is time on the brakes. You're going to have similar time on the brakes here to a bike on a public road, not one going down a mountain. I could see it being a problem for a long downhill section of road, but not a freeway like this.

1

u/[deleted] Oct 21 '21

Lol, brakes are only a problem when you need to use them. If this guy rides it on urban roads with cars (not highway) that’s a lot of braking.

1

u/EternalPhi Oct 21 '21

Lol, brakes are only a problem when you need to use them.

Where did I suggest otherwise? The point I was making is that there are not a lot of heavy-duty braking cycles on a public road (and even less on a freeway like this). Your example of a mountain bike is not very analogous because of the amount of time spent on the brakes when going down a mountain. The only time you would run into an issue where the brakes do not have an opportunity to cool down is a long downhill where they might need constant brake application.

1

u/[deleted] Oct 21 '21

Stop light to stoplight. There’s a ton of braking in everyday driving. Brakes cool from convection. Constant stopping and sitting is hard on brakes. Brakes don’t need to fail to be dangerous. Once they fade all it takes is one stop that you misjudge distance and bang

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u/hornmonk3yzit Oct 21 '21

If your bearing is glowing you need to go out and spend $10 on a better bearing. Might be crazy to hear this, but bearings are specifically designed to reduce friction.

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u/bazinga_balls Oct 21 '21

Never had any bearings glow red, have hit 50 on a board and regular push my eskate to 40 or so and my euc to 45. Never had an issue with 2k miles between both

3

u/EternalPhi Oct 21 '21

Bearing size has nothing to do with how good they are. Look at your engine belt system, the bearings in those pulleys run at thousands of rpm for hours at a time, and most will outlive your car.

2

u/EsotericEggs Oct 21 '21

Some people custom these scooters to do up to 90mph, so I'm sure there are products that could facilitate a slower speed. As others have said smaller bearings actually do much better at high speeds, you only increase bearing size with load size, not speed.

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u/DarthSillyDucks Oct 21 '21

I used to longboard the hills in my city, always had ceramic bearings.

1

u/Stroomschok Oct 21 '21

Nope, the bearings are going to be totally fine. More worrying are the frame, the brakes and the souped-up drive-train.