Especially post rain when the roads are just wet and feel, I don’t know, stickier. Anyone?
They are faster assuming you aren’t purposely riding scared.
They are faster assuming you aren’t purposely riding scared.
Interesting statement. Any evidence behind it? Serious question.
They are faster assuming you aren’t purposely riding scared.
Interesting statement. Any evidence behind it? Serious question.
This article seems to cover it and covers why both aerodynamically and from an RR perspective. In short, a wet tire is less tacky and the air pressure is likely lower when it is raining.
Thanks, good article. But, as l suspected, typically wet roads ARE slower (unless the moisture layer on the road is very, very, very thin … ).
If it is wet enough on the road that you are getting significant spray off the tire then there ought to be an increase in rolling resistance. I had a biophysics prof. (Bill Kier I think) who tried to model the energy needed to accelerate the water from the road after he noticed that he and his wife were slower on a tandem in the rain. I don’t recall the details of his experiment but his take away was it was a lot. That article seems to reference a slightly damp road but if it is properly wet and rainy then I think you must be slower.
Thanks, good article. But, as l suspected, typically wet roads ARE slower (unless the moisture layer on the road is very, very, very thin … ).
It would be a good experiment with some serious controls. My guess is there are a lot of other variables that could affect things including that chain getting dirty and inefficient 
Motor vehicles are definitely slower on wet roads. If you have a sensitive enough fuel monitor it is quite obvious.
Water pumping.
The sidewalls will also be cooler when wet so less supple and loose more energy.
Motor vehicles are definitely slower on wet roads. If you have a sensitive enough fuel monitor it is quite obvious.
Water pumping. The sidewalls will also be cooler when wet so less supple and loose more energy.
Yes, exactly, that is what the linked article said.
Cooler temps plus the tires pumping water off the asphalt with every rotation. And it is totally easy to feel the slowing effect on a bike.
I dont know if this is valid, but if you extend the exercise a little - say you were riding through 1/2 inch of water continuously, it would definitely be slower…
This article seems to cover it and covers why both aerodynamically and from an RR perspective. In short, a wet tire is less tacky and the air pressure is likely lower when it is raining.
The other thing you sometimes see in UK TTs is exceptionally still conditions when it’s wet. There have been some extremely fast days in wet conditions where riders do times they’re subsequently unable to beat.
Wet roads are definitely faster when you fall!
I’ve definitely seen this. Some riders are slower though through being cautious.
Air pressure can be effected during wet weather too. Humid air has slightly less resistance too.
I imagine in a straight line there’s a slight improvement in the wet. I’d bet you could lose more than anything gained with 2 corners.
So then if I understated this thread so far, and the article, in some instances wet roads are faster. In some slower. Ok. Got it.
Here is why I asked: I have done a local OLY 3 years in a row and my typical bike times are 65-66 min on this flat course (65-68 on all OLY courses I have done for context). This year it was 72 min (my slowest anywhere ever). Not that you can’t have an off day on the bike of course, but still…let’s assume I didn’t…Now unfortunately I do not have my NP from the prior two years which would be very useful, but this year my NP was 247 and I averaged 22.3 MPH…which should be around 65 min like usual. The only thing I can recall that was noticeably different from prior years (in both recollection and after reading my past race reports) was it rained the night before and the roads were wet. Not soaking. Not super light film. But wet…so maybe somewhere in between. Oddly my Garmin also said I rode 26.8 which even if I hit the lap start/stop button at the wrong spot shouldn’t amount to almost 3 miles longer than planned. Now maybe the course was ~3 miles longer and if so, ok, I was right on I guess, but I am trying to figure if wet roads could be minutes slower on a 40K assuming it wasn’t 3 miles longer (which I don’t think it was as the turnarounds were where I remembered them to be and the tranny zone was in the same spot). No way right? This must just be a combo of many things correct? What am I missing.
If you read the article that gerlach linked above, the bottom line is that wet roads are actually slower in the vast majority of situations.
Yes, the ATMOSPHERIC environmental conditions just prior to or after a WARM rain are a bit faster. And if a road is just barely barely barely moist (so little moisture that any moisture is below the road surface irregularities and your tires pick up zero water), then that too is a bit faster than a perfectly dry road.
But if a road is actually wet (i.e., if there is any water that is above the road surface irregularities and your tires pick up any water), then it is going to be slower.