actually, the "ABS reduces stopping distances" thing is a myth. it only does in very specific conditions: wet pavement and snow. on dry pavement and certain icing conditions, locking up stops in a shorter distance.

the real benefit to ABS in a motor vehicle is control. while a car with locked up brakes stops faster on dry pavement, it isn't steerable/controllable in the same way a car with ABS is.

i would think similar benefits would apply with bikes.

I don't know about you snobs but skidding stops me pretty fast in a clinch...

Skidding on a bike probably won't stop you as fast as resistance and a brake because when skidding your weight is typically going more forward... less weight over the back wheel = more likely to slip and brake (see what I did there?) traction which means it isn't stopping nearly as effectively.

I believe resistance and seated/near seated skip stops is probably the best brakeless stopping technique. But seriously, just run a damn brake - may never know when it'll come in handy.

Tyres: I thrashed through a Vredestein Fortezza SE and a Hutchinson Flash (both coloured blue) before learning/realising these things aren't so made for skidding to **** on city roads. I've got a Continental Ultra Sport kevlar on there now, which was cheap from MEC ($15CAD) so I'll stick with these until my parents bring me the Vittorias I ordered from ProBikeKit in the UK.

In short, if you're trying to stop - don't skid so much. If you are just skidding, just use cheap crap you don't care about - skidding through and flatting is no fun, especially when you're on the way to work one morning. If you're wanting to stop effectively using skips, get a thickass and/or cheapish tyre as mentioned above like a Gatorskin or something with a thick tread/kevlar/re-enforced bead or something.

YMMV, as always.

I like my Maxxis Detonators...and they have a cool stripe

i've tried armadillos (pretty good), Vittoria rando's, and a bunch of cheap ones.. i'd have to say rando's are my favorite. they last damn long and great for skidding.

I hate the losers that just say 'brake'. Fixed gear bikes are gnarly for the fact that you don't need a brake if you're smart. You should always run a brake. But using it isn't necessary. I feel that leaning over to hit the brake is more uncomfortable than just tossing in a skip or two.

Skidding and skipping are fun.

I had some gatorskins in my possession recently but the gear ratio on the bike I was playing around with them on was so much higher and it had drops (whereas my bike has bullhorns and a lower ratio) that I never really did any gnarly skids. To me it seemed like the tires were grippin pretty well.

I do have everwears though, and they skid like I'm riding on oil. Yes, they were made for fixie people who like to skid, and have a 5mm thick tread. Or maybe its a standard tread + 5mm. Not sure. Anyway, they are pretty thick, and at least for me have lasted longer than any other similarly priced tire.

I do also like the cheap ass Continental Sport approach though. I guess someone has to do some economic study... but a new cheap tire once a month vs everwears every two or three... not sure what is better. Probably the everwear (or similar) route is the way to go. My tires still look new. I have one on the front to wear it in as well, and will throw it on the back once my rear tire gets too... tired haha.

So, the google term of the day is, Soma Everwear. I have the 26's but I would definitely go for the smaller ones. Wayyyy too much sidewall on my tires.

Which is why you pop up the back tire and then lock it up, and when the tire comes back down, it is locked and will skid. In that skidding position you can shift your weight to the back which will put more friction on the skidding wheel, so you can slow faster. Also you can do some small turns with the skipping so you dont travel straight distance so much.
I use this method of skipping to slow myself down when im going too fast downhill and there is a stop sign ahead, cars pulling out, etc.
Resisting pedaling can only slow you down so much over a certain distance, and its much harder and tiring to resist pedaling going downhill. When you skip stop you can slow down much faster in a less distance. And I think skipping places less strain on your knees than resisting. And if you need to accelerate again quickly, it is easier to do so after skipping than resisting pedaling because your legs won't be as tired.

How exactly does it stop faster when the kinetic coefficient of friction is lower than the static?

for me, conti gatorskins skid like butter once they're broken in.

Continental gatorskinz, continental ultrasports if you're on a budget. They both skid well once broken in and continental tires are actually really grippy, even when wet. So. Lots of friction. Serfas Seca tires don't feel as good but are reaaaaalllly long-lasting.

i don't understand what you are asking.

what does the static coefficient have to do with the question at all?

the reason locking the brakes on a car and skidding stops faster on dry pavement is because it maintains a constant maximum amount of friction between the tyres and the road. ABS won't let the tyres reach that maximum of drag and allows them to slide for fractions of a second (which is functionally no stopping force). hence longer stopping distances with ABS on dry pavement.

wet pavement introduces hydroplaning - locked up tyres equaling no friction.

but in all of these cases, we're discussing kinetic friction.

touring/city tires; cheap and thick. they are actually the really nice for everyday city riding if you like riding more than changing flats (and they fit your frame).

I don't know what kind of riding you do, but as I ride my tire does not skid relative to the road. Hence the static coefficient of friction is governing my braking.

Locking the brakes on a car and skidding will not stop a car faster than applying the brake as much as you can without locking the tires. When you lock the tires, you switch to kinetic friction, which creates less friction force. Skidding (regardless of pavement conditions) is not a very good way to slow down.

http://auto.howstuffworks.com/brake2.htm

game. set. match.
:beer:

uh, the static coefficient of friction only has to do with surfaces that are not moving with respect to each other.

the only time your tyres experience static friction is when you're stopped.

when you brake, if the wheels are turning your stopping power is coming from rolling friction (which is a kinetic friction). if they're locked, you've got sliding friction (which is also kinetic friction). sliding friction almost always has a greater coefficient than rolling.

i agree that in most cases "locking up" is a dumb way to stop. but it's not because of the amount of force you can apply - it's because of the lack of control you have in how that force is applied.

My new Forte's go "VVVRRREEEEEEEEEEEEEEEEEeeeeeeeeeeeeeee" skidding... silly tread.

http://hyperphysics.phy-astr.gsu.edu/hbase/frict2.html

The amount of traction which can be obtained for an auto tire is determined by the coefficient of static friction between the tire and the road. If the wheel is locked and sliding, the force of friction is determined by the coefficient of kinetic friction and is usually significantly less.

http://ffden-2.phys.uaf.edu/211_fall...icFriction.htm

It is better, therefore, for your tire to be using static friction rather than kinetic friction. If the tire is rolling along so that the surface touching the ground is never sliding, then static friction is acting to slow the car.


It would appear that multiple school's physics departments disagree with you. As well as do I. Please do show evidence if you actually happen to know what you're talking about.

gatorskins. The other day i had to emergency skid stop and i was successful. Plus i've been skidding on this thing for about 4 months and it's still good.

hey so check it out


maxxis detonators are NOT great tires for skidding


I wore thru one in a month...granted alot of it was repeated on a 48/16 ratio....lots of gratuitous skidding

They were aptly called detonators. Tragic marketing.

damn them for having great sidewall decoration

Dude, you scribed at least half a dozen stupid accident stories over the last year.

+1 prepare to drop bank due to excessive skidding