tire for wet surface
 

So recently I took a spill. A car door was opened in my path and in a moment of panic I made the error of engaging the front brake way too hard. (I recently got a new bike with disc brakes, and I am still getting used to these much more powerful brakes). The front tire slipped on the very wet surface and I went down. Couple of things I did wrong here, but besides that, I was wondering if anybody had a recommendation on tires for wet surfaces. I am thinking of getting new tires anyway for the spring since my current fair weather tires need replaceing (Panaracer t-serv).

I am reading conflicting things; some say tread is needed to maximize traction on wet roads, others say tread won't do much, one should try to maximize the area of rubber on the road (slicks, maybe wider, lower tire pressure etc.).

Any experiences and recommendations?

Bike tires are too narrow, the pressures are too high, and the speeds low enough that hydroplaning isn't an issue. So a smooth tire offers the best traction on dry or wet pavement. Tread only improves traction in mud, snow, sand, or similar loose surfaces.

What he said. The only other factor would be the compound the tire is made from. Braking does need to be done with some finesse in inclement weather though. You can't just grab the brake hard, skidding is always possible. Traction is like a dollar bill, you only have so much to spend. You use it for braking, acceleration and turning. You simply overspent. ;)

Personally, I think rubber compound is the biggest factor in wet traction. The tradeoff is tire longevity but I will give up treadlife for traction any day.

I'll add a fourth positive to the first three replies.

You can believe any one of the hundreds of recommendations you might read. You might consider one from the Michelin Man:

"For road tires, grip depends mainly on the composition of the rubber compound, the inflation pressure and the match between these 2 parameters and the road surface."

That comes directly from the Michelin website, compound and pressure counts. Elsewhere Michelin states that tread patterns on a road bike tire only serves to make the rider feel more comfortable. YMMV and of course you are free to believe who you think might know the most about the subject.

I get comments about needing new tires because mine are bald. They aren't bald---they have lots of rubber left, they just happen to have a smooth tread pattern (slicks).

In the particular incident that you mentioned I believe there were other circumstances involved that no tire could overcome.

Now, taking all that into account, I use Continental Grand Prix 4-Seasons on my commuters. I made the choice specifically for their wet weather grip. Once upon a time there was a magazine article with wet grip test results. Accordig to that artticle, 4-Seasons were the best.

That said, I agree that pilot error needs to be taken into account. I've had disc brakes on my four-seasons all-conditions commuter for over six years. They are no more "powerful" than rim brakes. Either type can lock the wheel. Where they shine is modulation--control. They can be very finely controlled through impending lockup. Given their greater control, it's plainly seen that locking them up isn't a failure of the brake, it's a failure of the hand upon it.

So dust yourself off, and get some panic stop practice in. Both to get a feel for the brake, and to retrain your hand. Also, learn how to shift your weight back when stopping. Together, it'll significantly reduce your chances for face-plant. This is good advice for all brake types.

I use gatorskins until snow shows up. They work great in the rain. I actually just ordered another pair. Going to put the old ones on the Wife's bike.

I find the Schwalbe Supreme's to be "grippier" on wet roads than most tires I've tried. But yes, factors already pointed out by others are major players on this issue.

Thanks for the recommendation and yes, you're right about pilot error. :-) I guess my old bike's rim brakes were in poor condition or poorly adjusted so I never was able to lock them up. Also the fact that I'm left handed doesn't help. I did adjust the disk brakes for a 'winter setting' so that they don't lock up as quickly anymore. The rear brakes offer plenty of stopping power, after all.

+1) You were too Far to the right and so in the part of the street where people open car doors ..

no equipment will cure riding too close to the parked cars .

but essentially you need a bigger contact patch contacting the pavement,
but not so much as to hydroplane on the wet surface.


its more a rider problem than a tire problem ,
new tire wont fix not paying attention .

Elementary school physics says that traction doesn't change with the size of the contact patch. So not sure how it works in this case.

The problem with this statement is that it is addressing the wrong problem. No, a bicycle tire can't hydroplane but that isn't the issue here. Just because the tire can trap a layer of water between the tire and the road surface, doesn't mean that the tire can't lose traction on wet surfaces. JPprivate's tire "slipped on a very wet surface". I don't that he was traveling in a straight line when the tire slipped. He was probably turning a corner or even correcting for balance which is something that we do constantly on a bike.

I would argue that smooth tires offer acceptable traction only on dry asphalt. Once you lubricate the surface or, more properly, remove the unevenness of the surface, traction on smooth tires becomes very dicey. Think of what happen if you coat the surface with ice or paint or oil. Water isn't all that different from any of those. They serve as lubrication and reduce the irregularity of the road surface. Once you change the forces on the road by trying to change directions, that traction reduction becomes even more difficult to deal with.

Once you try 4-Seasons, you'll understand exactly how sketchy Gatorskins are in the rain.

Nice dry weather tire though.

I have plenty of rain rides under my belt in Gatorskins. Never had a problem but I'll give the 4 seasons a shot when I'm due for a new set.

I think it wasn't a tire problem, it was that you were riding in the "door zone". Move farther out from parked cars and you won't need to worry about doors.

In addition to riding a bit farther from parked cars, get in the habit of watching for heads in those cars. Easy to see once you start looking. Every occupied car is a potential door-opening threat.

As for tire choice, it can't hurt to look for a softer compound, wider tire, larger contact patch, and some tread pattern. I disagree that a narrow, high-pressure, slick is as grippy as a wide, lower-pressure, treaded tire in real world rain commute conditions. In the winter, streets are not only wet, they have a lot of debris. Suppose a narrow, high-pressure, slick tire rolls over a piece of debris - a very small pebble or a bit of twig. The debris blocks a large portion of the small contact patch. The high pressure means the tire deforms less, and the remaining contact patch is more likely to be lifted off the road surface. The slick surface also means there is no channel or sipe for the debris to sink into, which also tends to lift the contact patch. Now suppose a wide, lower-pressure, treaded tire rolls over the same debris. The debris blocks a small portion of the large contact patch, the softer tire deforms more easily around the debris, the debris also has a chance to sink into the tread pattern. Take it to an extreme and imagine rolling over a pebble in a 19 mm 170 psi tire versus a 40 mm 60 psi tire.

The other factor is tire compound. A softer compound will give more grip at the cost of shorter life and higher rolling resistance. So no harm in looking for a softer compound tire as well.

That said, no-one is going to put a 40 mm tire on his bike that currently wears a 19 mm tire, just for better rain traction. The actual choices are a lot more subtle - hmm, should I get these 23 mm tires or these 25 mm tires? So I suspect the amount of difference that this all makes is also rather subtle.

Personally, I commute year round in rainy Portland on 25 mm Panaracer Paselas which have tread but aren't advertised as a "rain tire", at about 100-120 psi, and they are perfectly fine.

Riding further away from car doors is not always an option, and we don't really know his daily riding environment/scenarios, so we are making an assumption that he has this option on a normal basis.

Bicycle tires for road use have a round profile with an apex at the top/bottom (whichever your perspective is at the moment), which means there is only a tiny patch of material actually making contact with the pavement. Combining this with high inflation pressure and force makes it extremely difficult to impossible for the tires to hydroplane. However if you are leaning on the sidewall this can change, either from the sidewall providing a larger patch of material that makes hydroplaning possible, or from the center of balance being shifted in such a manner that the tires can't keep solid contact with the ground because too much of the weight is shifting to the top of the bike making it too top-heavy while the bike is leaning.

Regarding road use, tread really only has the ability to make an impact when turning which would limit it's functionality to the sidewalls. Even then I'm sure that it's usually cosmetic.

The tread compound is your best friend when looking solely at the tires. A softer compound will definitely help you out with grip, but it will wear faster than a harder compound.

With that said, aging rubber can sometimes get too hard and essentially form a non-flexible glaze which resembles hard plastic that wouldn't allow any traction whatsoever. It's the same thing that can happen with your car's belt(s), but I haven't seen any bicycle tire compounds do this yet.

I really like the Continental GP's myself, and I can't say anything bad about them.

However I think that the most important thing here is not necessarily the tires, but taking better safety precautions while riding in the rain. Especially riding slower to allow yourself the opportunity for better situational awareness and reaction time. Combining safer riding practices with a softer high-quality road tire will certainly help keep you on your bike and out of the hospital.

Just shopping is not a universal cure .. though it does keep the money circulating ..

I also use Continental Grand Prix 4-Seasons on my commuter.
Excellent wet weather traction. However, brake modulation skills still need to be honed for safety.

I agree. I've had two wipe outs due to Gatorskin slipping, both times I was turning on morning wet road.

I love my Marathon Supremes in the wet...... But, they HATE snow..... not a good choice for a wintertime in Chicago

I know, that's why I have a Winter Bike. Front suspension MTB with studded tires.

http://i202.photobucket.com/albums/a...pscfc2e5ef.jpg

I'll throw in another recommendation for Marathon Supremes,best rain traction of any tires I've used. I've gotten air under the rear panic braking on a downhill in the rain.

Also another recommendation to practice braking and watch the door zone.

In most cases I prefer physics over engineering because I prefer a solid idea and a bit of hand waving to a bunch of tedious measurements, but there does come a point where the simplifications necessary to make physics manageable to the human mind cause things to get away from you in the real world. In this case in particular, I'm fairly convinced that the irregularity of the road surface and the flexibility of the tire surface allows the contact patch to play a role in stopping and cornering.

I would guess that there's a certain point above which increasing the size of the contact patch doesn't add grip, but I think that point is within the range of tires sizes and pressures commonly used.

With regard to the OP's question, I would add another vote for Marathon Supremes and GP 4 Seasons, both of which have great wet grip. If you prefer durability over sportiness, the Marathon Supreme is the clear winner. Otherwise, the reverse.

That does make sense. Wider, lower pressure tyre will spread itself in the surface irregularities more easily. Plus, there is a point where, under hard breaking, the tyre material starts shreading off the tyre and that causes skidding. But if weight is spread over a larger contact patch, there will be less force per square mm on contact patch surface.

Having said all that, from my experience, no difference between 23 and 32 mm as far as (wet) weather grip goes. As long as the pressure is not over 100 psi. Also, thread is counter-productive, unless there's some debris.