nrsmd

Is it possible to install new tires " backward?" That is, are treads omnidirectional or unidirectional? Never even considered that tread of my new tires could be spinning in the wrong direction.

02Giant 

Some cycling tires are unidirectional, some aren't. What tire do you have?

nrsmd

Vittoria Zaffiro Pro III 25 Tire, Black Fold, (700x25c) for my road bike Already installed

Maxxis Minion DHR II (not yet installed) and Maxxis Minion DHF (not yet installed) for my MTB

hillyman

May be an arrow on sidewall of tire if its directional

stanman13

If it isn't marked with an arrow on the sidewall it probably isn't directional. Looking at a web image of that tire, I would install it so that the point of the "v" in the tread hits the ground first.

Hoopdriver

This is the definitive answer.

mcours2006

Correct. I always look at it like the treads are arrows when looking down from your handlebar, and they should be pointed forward.

Ironfish653

Pretty much this^^^

Slick/semi slick road tire, odds are it's non-directional. The Forte's on my road bike are marked w/little arrows, the Kendas on the '10-speed' are not.
Any tread on a 25mm road tire is going to be pretty minimal, so it's not an 'OMG YOU"LL DIE!' if they do happen to be ridden 'wrong way round' I'd flip them, just because my OCD would demand it.

MTB tires, are usually directional, especially if they come in a Front/Rear specific set.

caloso

It matters on dirt, it doesn’t on pavement.

cyclintom

Pretty much but correctly installed directional tires stop a wee bit better if they are installed correctly. But why should you be riding so close to the limit that it would matter?

Retro Grouch 

Years ago I read someplace that tires with a "V" style tread should be installed so that the point hit the ground first in front and the opposite in the back. I once had a set of mountain bike tires that actually had 4 different direction arrows moulded in the sidewalls: one each for front and back wheels and for cross country vs. downhill.

For practical purposes, I think that it's real easy to over estimate the effect of bicycle tire tread. I think that, on pavement, the actual effect is whatever's the least possible number before zero. For real mountain biking I'll concede there's a difference. The ersatz mountain bike tires with a smooth center and knobs on the edges for "turns" are just for looks.

Having said all that. I mount my tires with the "V" points hitting the ground first front and rear. I just think that it looks better.

deapee

My front tire has been “backwards” on my cross for a while. It didn’t have arrows, but there are distinct v’s - the top of the v hits first. I don’t notice a difference.

canklecat

I wouldn't worry about it with the Zaffiros. I had a set of those on my road bike last summer. Within 500 miles the tread was pretty much worn down to barely visible, so it was like riding slicks. Even when new the tread didn't help stopping any better on pavement than the Schwalbe One slicks I put on later. Both tended to skid on the rear wheel on hard emergency braking.

Not bad tires for the money. A bit stiff at full pressure, and a bit sluggish at lower pressure. I like the Schwalbe One and Continental Ultra Sport better for speed and comfort on our rural chipseal and rough pavement, but I'd consider another set of Zaffiros for an economical city bike.

rumrunn6

I'm so bad at this, on my directional tires I write a big honkin' white arrow w a grease pencil which way they should rotate & yet I still mess up, even having 1 tire mounted correctly & the other backwards ... ugh. I survived the winter but next year I will be better!

case in point: my rear winter tire, which in no uncertain terms, says it's on backwards


this what the front looks like (which is mounted per the arrows on the sidewall), looking down at it. the chevron point faces forward & hits the ground first


same thing with my Proteks


pretty sure my Riddlers are not directional

prathmann

Makes sense technically since with a front tire you want maximum traction for braking while on the rear tire you want maximum traction for moving forward. The open end of the 'V' should grab the dirt for maximum traction. But in practice the effect is vary small and only applies at all when on loose surfaces.

cyclist2000

I have some tires that have a rotation arrows opposite for front or rear

hyhuu

On your Maxxis, the direction does matter.

caloso

I have some Kenda CX tires like that.

ThermionicScott 

The most compelling reason to make sure your road tires are installed per the arrows is to prevent nosy busybodies from informing you that your tires are on backward.

one4smoke

It matters on pavement if there's water present.

79pmooney

So far, every tire I have mounted on my various fix gears has rotated just as well after I flipped the wheel. I hope never to find one that doesn't!

Ben

caloso

Because of hydroplaning?

mihlbach

no

Can a Bike Hydroplane? | BeetleBag

caloso

Exactly.

MikeyMK

On a rear wheel, yes. But not so on the front.

Your rear wheel drives forward, but your front wheel effectively drives backward (braking). The V pattern cuts through surface dirt and disperses it out the way during wheel slip under power, but the V actually scoops this dirt under the tyre if you use that wheel for braking. V-tread isn't ideal for a non-driven wheel, but when mounted, the tip of the V has to be pushing forwards under braking. This way, any slip (skid) pushes the dirt out the sides and the tread digs into the surface - and that can only happen when the V is pointing to the rear of the bike when it's on the top of the front wheel.