Bought Continental Tyres for Bicycle (3rd September 2012)
The manager of Hadron Cycles made the case that slick (aka treadless) tyres work just fine in the rain. Because they are so narrow on a bicycle, they easily displace any water and make full contact with the tarmac.
Today I bought a pair of Continental Gator Hardshell tyres and had them fitted. Also got a pair of spare Continental inner tubes as I’ve had so many punctures with my previous tyres.
Naturally, wet tarmac is less grippy than dry tarmac so one must always be extra careful in wet weather. The point stands that treaded tyres have less rubber on the road and more rolling resistance. They might bite through a bit of building dust but riders naturally take it easy on adverse surfaces.
The rounded surface of the tyre further helps to push water out of the way. Many aeroplane tyres don’t have tread, especially military jets. The contact patch is so small compared to the weight that they always displace the water.
Car Tyres are Different
In contrast, car tyres have a wide, flat surface. There is a very large contact area compared to the weight, so they can’t displace the water. This makes them quite prone to float above deep puddles, called aquaplaning.
Car tyres use treaded tyres so the high blocks can push water into the low grooves. In effect, the tread creates a row of skinny slick tyres with small gaps between them.
On a bicycle, the tyre is already so narrow that there’s no advantage to dividing it any further.
All Good! (21st November 2012)You definitely don’t need treaded tyres on a bicycle in the rain.
After several wet weather rides, including about of deluges, they have been totally safe. The theory and experience is all true. The only sketchy moments have been riding across manhole covers with raised edges that are also rotated at an odd angle to the road. This has made the front tyre skid a few centimetres to the side before it climbed up the raised edge.
This would also affect treaded tyres. You should always beware of metal covers and painted lines in wet weather.
Also, the reduced rolling resistance is staggering! Going from mountain bike tyres to treaded road tyres was like night and day. But these high-pressure slick tyres…it’s at least that much difference again.
Since buying them I have had no punctures from road debris. I damaged the rear inner tube after removing a broken spoke but that’s no fault of the tyre.
Astonishingly reliable rubber. I must have saved hours of journey time by avoiding punctures.
I’m convinced, once more, about the advantages to good (aka expensive!) tyres on a road bicycle.