cycling in the wet
-By: Tomas Swift-Metcalfe
Last modified: January 4, 2014
cycling in the wet -precautions to take
I had my first wet ride of 2014 today and it got me thinking: Riding in the wet is very different to riding in the dry. I am aware a lot of people have trouble with this and I myself have had my fair share of issues with it.
vision in the wet
You can’t see the road surface so well in the wet, be water on the road, or on your glasses or in your eyes. Things might be hidden. In the Tour de San Luis in 2012 we got tremendous hail right on the first day. With about an inch of water on the road, which was in fact a motorway I couldn’t see there was a little step between the hard shoulder and the main carriage way, this and the fact that this step was covered in that smooth tarmac they lay over cracks and joints meant I slipped an fell. I’d suggest never removing your glasses, mucky glasses beats wheel spray in eyes any day. I’d suggest getting to know the way a particular road system is before racing on it too… If you can, reconnoitre the course.
Tour de San Luis 2012
cycling caps -get one for the cold and wet
The cycling cap is very useful, even when worn under a helmet. It keeps you a good bit warmer, even in the wet. Also some people find (I’m not one of them) the the bill on the front of the cap helps keep water off their eyes.
road surface, oil
Here in the Algarve we have a problem: The roads are very smooth. This is great in the dry of course, but in the wet they’re lethal, and no time is worse that after a prolonged dry spell. During a dry spell, oil and grease for cars, trees and the tarmac itself accumulates on the road surface. This isn’t an issue in the dry, except in the wet it comes loose and become slick as ice.
Those bumpy, gritty, heavily cambered roads in the UK might not be comfortable for cycling, but they’re far safer. However at junctions (and cycle paths ironically) the roads are sometimes painted and that paint is super slippery in the wet. The lines on a road or pedestrian crossings are very slippery!
Cobbles tend to be more slippery than tarmac, and their edges can cause the tire to slip provoking a fall. Watch out for ‘polished’ stone cobbles, these are hard to walk on while wet, yet alone cycle on. Here they’re used as the white in pedestrian crossing. It takes longer to slow down on cobbles.
traffic and stopping distance
Bikes aren’t as quick at slowing down as cars, and this can cause problems in the wet. Also if your rims are wet you will need at least an extra 2 m to stop as you need the first pass of the wheel to clear the water of the rim and allow the breaks to bite.
I’m not sure if there’s been any study on this, but obviously your lean angle counter the centrifugal force while cornering. The friction between the tire and the ground is reduced in the vertical plane and increased in the horizontal plane. So that, added to the already reduced friction can make it difficult to stay up right. Many cyclist believe trying to keep the bike vertical works… But I suspect this doesn’t result in more speed through the corner. Changing trajectory on the other hand, so that you’re leaning as little as possible works. Wider is safer.
In theory this isn’t a factor as the coefficient of friction remains the same, it’s a constant in both cases (high pressure or low pressure), as the force acting against the surface is the same… It’s a hard one to believe.
From experience I’d say to run the tire at the stated pressure no matter what. Run the pressure in the upper range if your heavy >70kg, or lower range if you’re light. No trick here I’m afraid, despite being one of those cyclists that would be taking air out of the tires on a rainy day.
I used to race on excellent Vitoria Corsa tubular tires. The problem with these is that they were lethal in the wet. They were pumped up to the max to prevent punctures. These were absolute rubbish in the wet and I think this was due to have a no tread on the sides, so if you leant in a lot they’d give. Tread helps in the wet.