Todius Treads

[Shaughn]

...Why cut the treads in any direction then?...

The only reason for directional treads is for water evacuation. Even backwards, the channels are better than tread patters with no vertical channels that lock the water in, leading to hydroplaning. The classic Wrangler Radial that was stock on 80's Jeeps was a good example of this problem. Unless you give the water a place to go, the tire rides up on it, instead of through it. Seeing directional tires mounted backwards on a car still drives me nuts though, and I see it everyday.

There are ALOT of tire companies that use A single tread for front and back, you simply reverse the mounting. RoadRiders i do believe are ANOTHER that do this, depending on the sizes you need. The only danger is because of the ply set up, NOT the tread or water pushing ability. However, Avon, and many other companies who do this, use modern materials, and the danger that used to be common with reversing ply tires is not as prevelant as it used to be. I really wouldnt worry a hair on my head about it to be honest.

Even though I'm well versed on anything radial, unless it's a trailer or Ag tire, I don't know much about bias tires.
Why is it a problem mounting two rear tires in the same direction? Is this all about steering pull?

[bwringer]

It looks like a few people are still stuck in car-based thinking. The wide, flat tires on cars can and do hydroplane in standing water at street speeds, and the tread design makes a difference.

The contact patch on a motorcycle tire is so narrow that the tread design makes little to no difference in wet traction at street speeds. The tire compound has a lot more to do with wet traction than anything.

If you're battling heroically for the lead in the MotoGP at 150+mph, then yes, you need some sort of tread voids so the water can escape, and the shape/direction of these makes a little difference.

Basically, it's extremely difficult to get a motorcycle tire to hydroplane, unless you combine very high speeds with very deep water, and little to no tread.

In the case of the rear Avon Distanzia I've mounted on the front of my VX800, there are plenty of void areas for water to escape, even very deep water, and the shape or direction of these simply makes absolutely no difference for street riding in the wet below 200mph.

However, the direction of the tread blocks DOES make a difference in soft surface riding, which is why I followed the manufacturer's advice and mounted the rear tire backwards on the front.

Look at it this way: the front tire needs to develop traction to stop the bike. The rear tire primarily needs to develop traction to propel the bike.

Now let's imagine a rear tire propelling a tiny motorcycle to the right side of the screen in soft dirt: ===>

You'd want the rear tire to leave tracks like this:
<<<<<<<<<<<<<<<<<<<<<<<

Why? Imagine the rear tire starting to slip. The "V" shapes push dirt to the outside. The untouched dirt on both sides of the tire is available to resist this push.
xxxxxxxxxxx
< < < < < <
xxxxxxxxxxx

If the rear tire were mounted the other way around, only the dirt in the center of the tread would be available to resist the push:
x>x>x>x>x>x>x>x>


Now let's think about the front tire. Our intrepid tiny rider is once again headed to the right side of the screen, when suddenly a huge smiley appears and he needs to stop. The tracks should look like this:

xxxxxxxxxxxxxxx
>>>>>>>>>>>
xxxxxxxxxxxxxxx

Again, the dirt (xxxxx) on both sides of the tread is available to increase braking traction.

With the tire flipped to the same direction as the rear, only the dirt in the center is available to resist the force:
<x<x<x<x<x<x<x< x<x<x<



Keep in mind that on a pure dirt tire, the tread pattern is usually not directional -- it's made up of square or rectangular blocks, since the rear is used for far more braking in the dirt, and noise and street traction are also not considerations. On some ATV tires, you'll see a tractor-style chevron tread.

Overlapping chevrons, larger, less flexible tread blocks, and other differences are compromises designed to help a streetable tire make less noise, last longer, and work better on the street. The Distanzias are usually considered about 80% a street tire, 20% dirt.

If I took my rear Distanzia (the one that's mounted on the front) and flipped it around so it's rotating as if it were a rear, it would make no difference at all on the street, even in the rain. However, this could compromise braking on soft surfaces. So it's mounted "backwards" to give me the best possible braking traction whatever the circumstance.


The issue of ply separation (the idea that the tire will unravel if it rotates the wrong direction) is simply not a concern with modern motorcycle tires at street speeds. It could happen with some poorly made tires many years ago, but it's not an issue these days.


One issue that will probably come up as the miles go by is front tire wear -- the tread blocks in the front are much deeper than a street tire, so I'm curious to see how they will wear at the edges, and what sort of scalloping I'll end up with. I have no idea how that will all work out, but I'm keeping the front air pressure on the high side to attempt to minimize scalloping.

[silverhorse47]

This is such a great description. Thanks.
S.

[nisom512]

poor baby its to bad she has no clue how dirty she is going to be in just a few posts

[Flaggo60]

Installing the latest Dualsport tires on my 650G is a thought that I've toyed with from time to time. I do wonder that the use of the tires on the street will lead to a few slippery moments though and thats where I spend most of my hours. Have you seen any sign of this or are you as comfortable street riding with them as any other street tire?

[donimo]

I like those avons, they look JUST like the michelin reggae's I had on my 50cc, awesome tires, lasted three years with no real wear, not many miles at 60k/h but my 250lb ass on there wore the stock chen shing off in 6 months...

can I get them in these sizes?

Front Tire3.00-18Rear Tire3.75-18


would I have to run rears too?