This is really a general question I guess, but is aquaplaning made worse the wider the tyres you have on your car?

I think its affected mostly by tread style, tread depth, and weight placed on the wheel. If the treads channels aren't deep enough, water will get under the blocks too. Most should have a good tread pattern to push water out the sides, but if you fit directional tyres the wrong way (e.g. the --ROTATION--> arrow is pointing the direction the wheels would turn in reverse instead of fowards) then it will guide the water to the middle of the tread instead of out the sides. The more weight on the tyre, the more downward pressure it has to get through the water and to the road. Wider tyres technically spread the load over a larger area, so there is less pressure, and a longer distance to push the water, so might make it worse, but wide wide tyres don't really fir magnas.

This is really a general question I guess, but is aquaplaning made worse the wider the tyres you have on your car?

Without a doubt it is made worse, however as mentioned tread pattern and the ability of the tyre to disperse water to the sides is also important, the better brands do this very effectively.

Also water depth and flow play a big part too not just the tyres

Short answer - The wider and cheaper the tyre, the more suspeptable it is to aquaplaning.

To keep it safe, try to keep to GOOD 235 tyres. I use Kuhmo KU31's for example and have not had any issues with it. Used to happen all the time on Nankang NS2's of the same size. Dangerous tyre.

Short answer - The wider and cheaper the tyre, the more suspeptable it is to aquaplaning.

To keep it safe, try to keep to GOOD 235 tyres. I use Kuhmo KU31's for example and have not had any issues with it. Used to happen all the time on Nankang NS2's of the same size. Dangerous tyre.

Couldn't agree more Nankang shouldn't be allowed on any car about as good as recaps.

Have a look at the articles on Autospeed as these seem to be unbiased and accurate stories normally and have some interesting takes on various automotive aspects.

One thing I recall reading is that the size of the contact patch of a tyre is dictated by the weight on the wheel and the tyre pressure.

eg: http://autospeed.com/A_108915/cms/article.html
eg: http://autospeed.com/cms/A_110774/article.html

Another thing to note from my experience is that LOW tyre pressures (ie: like 26psi as manufacturers used to recommend) can INCREASE the chance of aquaplaning compared to high pressures (like 35psi and above) because the tread pattern actually collapses and closes the water channels.

The only time I had chronic aquaplaning was in a KE55 Corolla with 215/60/13 Yokahamas that were < 50% tread left and on Hotwire 13x7 mags - I loved that car - my first foray into modifications.


So, no, wider tyres do not instantly mean more aquaplaning. The design of the tyre & tread pattern will have more impact than the width.

IMO: If in doubt, run higher tyre pressures. 60psi is safer than 20psi in the wet.

Couldn't agree more Oggy. When you consider around 6l of water per second is required to be displaced by tyres @ 100kmh in order to keep contact with the road, the psi would make a HUGE difference to the tyres ability to perform that task.

Depends entirely on the tyre - even what pressures you should run. The difference in size between, say, 225 and 245 is irrelevant compared to the difference between, say, R888s and P-Zeros.
Basically, stick with decent quality wide tyres and run 36-38psi. KU31s are a great tyre for the price, as Life said.

Depends entirely on the tyre - even what pressures you should run. The difference in size between, say, 225 and 245 is irrelevant compared to the difference between, say, R888s and P-Zeros.
Basically, stick with decent quality wide tyres and run 36-38psi. KU31s are a great tyre for the price, as Life said.

I'm now running ku31s in 235 and ill let you guys know how they go compared to my old tyres when i get back in the car this weekend.

Those nankangs are horrific, as soon as it's wet it's hell, even in the dry they're pretty poor. OP, as mentioned many times above, yes tyre width increases aquaplaning.

No, tyre width increase does not increase aquaplaning.

No, tyre width increase does not increase aquaplaning.

So you are saying...same tyre, same diameter, same car speed, same tyre pressure, same conditions only difference being the width of the tyre = no difference to aquaplaning?

No, tyre width increase does not increase aquaplaning.

I'd like to see proof on your theory.

Take Kuhmo KU31 for example

Sizes available:

225 40 18
235 40 18
245 40 18

Tell me which is more likely to aquaplane if they are all in the EXACT same conditions?

Here's some quotes from Autospeed.com...


For example, say that the weight on the tyre was 900lb, and the tyre pressure was 10 psi. That internal pressure means that each square inch of area can support 10lb, so, in this case, the contact patch will be 90 square inches. If the tyre pressure was 30 psi, the contact area would be 30 square inches, and if the pressure was 90 psi, the contact area would be 10 square inches. This has been found to be almost exactly correct for most tyres (the exceptions being so-called run-flat tyres, or tyres with extremely stiff sidewalls). For most other tyres, carcass structure will have an effect, but by far the major factor is tyre pressure.

So, as you can see, the size of the contact patch of a tyre is not related to the width of the tyre - it is, in fact, proportional to the tyre pressure. What will change with the fitting of a wider tyre is the shape of the contact patch - it will get wider, but shorter longways.


One issue to consider is that, for wet weather driving, despite what you may have heard, it is better to increase your tyre pressure, not reduce it. The reason is that there is a relationship between tyre pressure and the speed at which there is the onset of aquaplaning. In the Imperial system, the equation is 9 times the square root of the tyre pressure. So, if your tyres are at 25 psi, if you drive into a puddle that is deeper than your tread depth, you will aquaplane at 45 mph (72 km/h), whereas if your tyre pressure was 36psi, you would aquaplane at 54 mph (87 km/h)



So, since the contact patch size doesn't actually change, the likelihood of aquaplaning is the same.

After a failure in finding technical information on KU31 tyre tread patterns at varying widths, then I will admit to making one assumption! :)
Assuming that the proportion of water channel widths to width of tyre remains constant (ie: wider tyres have wider water channels), then the wider tyres have exactly the same amount of rubber on the ground as the narrower tyre.


So tread depth and tyre pressure are the deciding factors, not tyre width.




Oh, and it's actually Kumho, not Kuhmo, although I pronounce it the way you typed it - the other pronunciation is a bit rude. :)

So none of that was proof unless you believe Autospeed as gospel. :)
But I've been following the publication for many years and like the independence the main writer shows and do trust what I read on the site.

Now the only thing I can't prove/disprove (to my own satisfaction) is that the shape of the contact patch affects or doesn't affect the chance of aquaplaning.

Any takers?

Wow think I have opened a can of worms on this topic, very interesting reading, thanks everyone for your input, happy easter. Cheers

Just a quick quote before i head out (will expand later when i get home).


In brake tests from 100km/h, the wide tires improved stopping distances by 5.2m. However, aquaplaning occurs at a speed of 69km/h for wide tires as opposed to 80km/h with the narrower tires. .

Definitely keen on that explanation.

It makes sense that the contact patch would be quite similar for wider tyres, but why then do fatter tyres provide more grip? Technically they'd have the same amount of rubber on the tarmac right?

Is it just length widthways vs length longways?

I found some sources for that quote from Caz_375, the couple I looked at were copy & paste jobs. This might be an original report of the story? http://www.motorauthority.com/blog/1027043_are-wide-tires-better-than-narrow

ADAC in Germany did some testing. I tried to find the actual test results in German, but could only find an index to a 2007 publication but no actual text, so I don't know the parameters of the testing. I wonder if they were the same tyre make & tread pattern, same air pressure, tread depth, etc. Would be very interesting to have more info.

I guess something I haven't considered is the depth of the water.
If the water is deeper than the tread of the tyre, then the contact patch calculations of pressure and weight don't mean as much because it's the water contact patch that will help lift the car onto an aquaplane, not tyre to road contact (=grip) that we would have to consider.
So now I'm going to change my mind :) and say:
"wider tyres can aquaplane just the same as narrower tyres as long as the water depth is close to the depth of the tread pattern, but as the water gets deeper, the wider tyres chance of aquaplaning increase more than the narrow tyre. Wider tyres offer more grip in the wet, just as long as the water isn't as deep as the tread left on the tyre."
This means that I now think wider tyres do have more chance of aquaplaning (in the right conditions of deep water)

I think I was wrong earlier to say wide or narrow is the same, but my above/latest theory fits better with my initial guess.
(and theory is all it is because I've only tested aquaplaning about 3 times in 20 years on the road - lots more on the track, but racing slicks DO NOT count :) - and none of it was scientific testing)

My worst example of aquaplaning was in a 1981 KE55 Corolla Coupe with 205/60/13 tyres - I was driving on Victoria Rd in a big downpour, east bound at the railway bridge at Rydalmere - the road at the bottom of the bridge was a swimming pool and I skated across the top of it - very eerie when the steering goes super light like that and you just sit along for the ride.