How wheel size affect the Acceleration

In this video, we have explained how does the wheel size affect the acceleration of the vehicle.

[johneppstv]

This video does not include the added horse power you get from stickers.

[daviasdf]

Not quite correct this time: The referenced 15" to 19" decrease in acceleration is not due to the change in the distance between the road and the axis of rotation of the wheel (19" wheels will use a lower profile tire, so the actual radius from axis to road remains the same). The actual reason is that, in a larger wheel, the mass of the wheel is greater and distributed further from the axis of rotation, thefore increasing its polar moment of inertia. Rotational acceleration of the wheel = Torque/(moment of inertia). Therefore, if the moment of inertia increases, the wheel will spin up more slowly, even if the outer radius is identical for both wheels. A wheel with larger moment of inertia would spin up more slowly (think of each wheel+tire as a flywheel...). Additionally, the negative impact to performance is also evidenced in braking performance.


Keep up the great work. I enjoy your content.

[franco]

A test has been done between a bmx, a mountain bike and a road bike (it's on Youtube btw). On 100 meters the bmx won but over this distance it was the road bike.

[see]

Great video!
In discussion with other car people about wheel size, there is a sometimes confusion with the torque affects on acceleration vs breaking.
A video dealing with the differences would be helpful.

[DTechnologyservices]

Guys listen just get your factory rims dipped in black chrome or rose gold and be done with it or go to a rim shop and let them hook it up nice.

[shaunmax]

I just wanted to know why my shiny knew 18.5 GT wheels are slower than my 17’ bullet wheels and I walked into a room full of mathematicians 😔

[pbierre]

There's even more effect....lift the car off the ground, and think about the axle force eaten up just to get the wheels spinning faster....which goes up as wheel-radius squared. The 10% smaller wheel has 20% less rotational inertia.
This effect adds even more to the "sprinter effect" of smaller tires. The braking system will be more assertive, for the same reasons discussed here.

[lovethesmellofracefuelinth]

The stock 0 to 60 in my Challenger SRT8 was 4.9 with 20" wheels and runs in 4.6 after switching to 17s, so I can confirm what he says is true and will do even better after airing down the tires because that was at full air pressure and still spins a little. I should add that it has 305 Mickey Thompson drag radials and just got them on recently when we replaced the rims, plus that was on a freeway ramp entrance and on an incline. So on a flat surface with about 15 psi, it should hook well and think that I should be able to get close to 4. Especially if I can master the line lock as launch control, but you have to throttle the RPMs just right and know when to engage or it spins like crazy and just goes up in smoke lol. It looks cool, but you're not winning if you're spinin

[objective]

It's the same concept if you have a manual transmission. You will not stall the engine if you start from 1st gear then if you start from 4th gear.

[buffi]

over 12 miles say your milage reading will be less on larger wheel, then also on the car test the brakes are less effective on large wheels

[obtrunco]

I think some of you in the comments are confused. He's talking about overall diameter although he's generalizing saying "wheels". But regardless of the math it's hard to fathom because in a drag race, having a larger diameter / circumference (w/o exaggeration) you'd cover more ground with less power. Although the smaller diameter will complete it's rotation sooner, it has covered less distance than the larger one. So during the course of the race with identical cars, the one with the larger tires will be overtaking the one with less diameter.

[RexinOridle]

It’s true that smaller diameter wheel will produce overall more wheel torque. But yor car’s acceleration depends on multiple factors. If your wheels produces more torque than the limit of friction of your tires, you are not gonna accelerate any faster. Your wheels will just freely spin at peak torque. Instead, larger diameter wheels will make you go faster. This is why you don’t put 15 inch on a Tesla with low profile tires, nor on a Koenigsegg Regera.

[rondhole]

Thanks for trying to explain some. The change of wheel size only change moment of inertia, results in lower angular acceleration or acceleration since the total radius of the wheel with tires the same. Changing total wheel and tire sizes changed the moment of inertia. I ~ mr2 and reduce total acceleration because larger r with the road as the axis. Accelerating a= alpha x r . Alpha is Torque/ inertia. So acceleration ~ 1/r .

[stevedekorte]

Isn’t this only true up to the amount of torque the wheels/tires can handle before slipping? Non sports cars might not reach this limit, but performance cars can easily exceed grip, requiring larger wheels to maximize acceleration.

[abdullahz]

Ah this is why my E200 with 15" rims is faster than my E230 with 19" rims. I knew it hehe my friend was bragging that he won

[abuharris]

thank you for a very simple explanation

[racereid]

so what i would like to know is if bigger wheels add performance on cars that have to much power for the wheels and if not launched at the right rpm will spin. if wider tires help or hurt performance. weight of extra wheels vs more grip to put down unused power

[rajaryanigdncxhadk]

very good video, well explained, thank you for knowledge, helped mt a lot, cant thank you enough . Pls make more video on mechanical/ automobile

[เด็กดีมีสุข-วฃ]

it similar to increase or decrease final drive ratio by just change bigger or smaller wheel.

[Roger-uzbh]

So Smaller Wheels will give more Accelaration and Larger wheels will More Top Speed right?

and also, what's up with tractors using big rear wheels..