It was raining fairly hard today, but I decided to go out for a ride, about 5 miles, on my Coker. I haven’t ridden in the rain for awhile and it got me thinking: why is there no change in stability from good conditions?
Do unicycles simply have more traction than a standard road bike? I’ve never worried about turning on gravel or sand on my uni, but that threat is far more real on a bike. Even with the tread on my tire wearing low, I didn’t experience any hydroplaning.
Well, you do have a lot more weight on one tire, and you go much slower on the uni than on the bike. However, I noticed one time when I was riding indoors, my wheel picked up dust from the linoleum floor and became very slick. It was weird, because I found that I could get my tire to slip in sharp turns, and I could actually kind of drift. On a bicycle if your front tire slips, you fall, however on the unicycle it was actually kind of fun to ride on this slick, dusty floor because it was predictable and I didn’t fall when I slipped. Maybe there is the same amount of traction, but it has less of an affect on the rider?
Unis definitely have more traction; all the weight on one wheel, not to mention generally lower speeds and slower acceleration and deceleration.
But neither unis nor bikes can hydroplane (well, except maybe the new super-fatty bikes). The tires are too high-pressure and narrow.
That’s what I’ve been trying to tell everyone who has told me not to ride in the rain… of course, I’m always wrong 
Everyone I know is a non-unicyclist, but they do bike recreationally, so they try to tell me that it’s idiotic, dangerous and that I’ll slide around a lot. I submit that it is more dangerous, but not as severely as they seem to believe. Until you ride a uni in rainy conditions, you can’t accurately say what it is like.
I do find that I UPD more in the wet than in the dry but it is not due to traction but more because I find it harder to see undulations in the road surface when its wet and dull.
When you look at some of the slopes Kris, Turtle and others ride down you have to think that unis do have more traction though.
Frankly, they’re wrong. Not only do unis have all their weight on one point, they also don’t have weight transfer on braking. When a bike applies its brakes, the bike’s weight transfers to the front wheel, which means the rear wheel will skid at the slightest provocation. We don’t have an analogous phenomenon; we automatically transfer weight back before we brake (or else we fall off).
Unis also don’t lean as far as bikes in typical usage, so the problem of having your wheels go out to the side isn’t as prominent.
It’s certainly possible to skid a uni wheel but it’s much harder than on a bike.
The short answer is yes, UNI’s have more traction. However, the higher speeds and leaning turns are what makes bikes much more dangerous in wet/slippery/sandy conditions.
and think of the amount of rubber touching the ground at any time
The amount of rubber touching the ground is a function of the PSI of the tire(s). A unicycle with a tire at 60psi will have the same amount of rubber touching the ground as a bike with two tires at 60psi (well, slightly less assuming that the bike weighs slightly more). Uni riders tend to use lower pressure than bike riders, but other than that this isn’t a major contributor to differential in traction.
Of course they do
As I tell everyone when I ride uni in the snow, “It’s all wheel drive!”.
But seriously, with slower speeds and generally less hard cornering, the forces working to slip a tire are much less.
As for managing a dust covered tire on a slippery floor, that sounds comparable to a slick mud trail. As long as it’s consistently slippery, it’s not that difficult and can be lots of fun.
Yes, unis have more traction than bikes, but they also have less stability.
I have slid around in the mud, on wet roots and rocks, I have been able to sustain slide up to a couple feet, but more often than not a good slide leads to a UPD.
Bikes have the stability advantage, two wheels vs one, so like comparing a car to a motorcycle, stability outweighs traction more times than not.
Imagine trying to powerslide a uni, tried it, it’s edgy 
There have been times when I got traction where bikes were spinning, but only because they had too much weight on their front wheel, i.e. poor technique. My favorite “move” is to outclimb bikers, it blows them away that a unicyclist can ride up a hill, but then to climb as faster or faster than a bike 