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Discussion Starter · #1 ·
Can someone please explain to me why the tread pattern is reversed on the front tire? When I look at the rear tire, the tread pattern would be pushing water to the outside of the tire. But the front is just the opposite of the rear. It has the same(or nearly the same) tread pattern, but reversed. So it appears to be forcing water towards the center. Am I missing something here? :hmm2: My tires are Michelin Pilot Power 2CT's btw.
 

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make sure the arrow on the both tires are pointing forward, could been whoever installed your tires put them on the wrong way, ive seen this happen before.
 

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Discussion Starter · #3 ·
make sure the arrow on the both tires are pointing forward, could been whoever installed your tires put them on the wrong way, ive seen this happen before.
They are on the correct way. Trust me, I looked before, and after they were installed. :) And it's not just my bike. My buddy's 08 ZX-10R is the same way.
 

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I would have said it's on backward too.. The young dude at work had new tires put on his cbr 250 last Xmas and the front was on backwards..
 

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Discussion Starter · #5 · (Edited)
I would have said it's on backward too.. The young dude at work had new tires put on his cbr 250 last Xmas and the front was on backwards..
It's on the right way. So we can eliminate the possibility of my tire installer being careless. It was obviously designed to be that way. The only other explaination is someone at Michelin messed up the arrow direction when they designed the tire mould, but I can't imagine that could possibly have happened.

And my rear tire is on correct as well. So that's not the issue either. ;) Here's how they mount on the rim looking at them from the front of the bike.


And here's a close up of the front tire. Note arrow direction as well as tread direction.


Several of Michelin's tire sets are this way, i.e. the front is reversed. However, they also have sets that the tread runs the same direction on the front and rear.
 

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b/c the force applied to the front tire (breaking) is the opposite direction from the force applied to the rear tire (acceleration).

*That's just my personal speculation, I've never had the opportunity to ask a tire rep.*
 

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Discussion Starter · #7 ·
b/c the force applied to the front tire (breaking) is the opposite direction from the force applied to the rear tire (acceleration).

*That's just my personal speculation, I've never had the opportunity to ask a tire rep.*
I follow your train of thought on that. And it makes sense. However even under braking the front tire will still be spinning forward. So the tread will still be traveling the "wrong" direction.

I'm looking at this from a water shedding/displacement standpoint.
 

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Yeah idk man, I know it's rotating the same direction as the rear tire and would have to shed water in the same direction but it has to have something to do with the direction of force being applied to the tire, b/c thats the only thing different about the two. Maybe the tread is designed to push water and debris out away from the tire in a corner where you're counter steering and need maximum grip?
 

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Yes I would assume it's for when your turning and on the side of the tire rather than just going straight
 

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Discussion Starter · #10 ·
Yeah it could be for turning. It still seems odd that it would be moving water from the outside edge of the tire towards the middle (or to the outside of a turn, however you want to look at it). I would think it is just as effective to have the tread running the same direction as the rear, or possibly more effective, so long as the water is displaced.

What puzzles me is Michelin has tire sets that have the front tire with the tread running the same direction as the rear. As a matter of fact, one of those same direction sets has the exact same tread pattern as my tires. The only difference is my tires are dual compound and that set was not. So apparently whatever the logic is behind this doesn't apply in all circumstances.
 

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No eyed dear!!
 

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I've always wondered this myself, as to why the direction of the front tread appears to be wrong. I don't know but I have heard, as ET said, that it has something to do with the different forces exerted upon the tires.
 

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Discussion Starter · #13 · (Edited)
The best that I have come up with goes like this:

Say you are riding along and hit a puddle. The front tire hydroplanes. The front tire slows down (in relation to the forward momentum of the bike) or stops turning altogether, either because the rider grabs the brake or it just naturally does so on its own. (Imagine a stationary tire moving across a surface, with tread running in the forward/reversed direction. It will really help you to understand the following)

Now, with a tread that is "reversed": the forward momentum of the bike, coupled with a tire that is no longer rotating at the right speed would cause the reverse tread to come into effect, channeling water away from the center of the tire. Therefore letting the tire settle back down and regain traction.

Now, with a tire that has tread running the "right" direction: It would attempt to not hydroplane in the first place. However, if it did hydroplane, and the brakes were applied, the tread would pull water inward towards the center of the tire. As a result, the hydroplanning effect would be worsened.

Clear as mud? Does this sound logical to anyone else? Or should I just contact Michelin and see if they will shed some light on this? ;)
 

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I'm a little drunk right now, but even though the tire has slowed down 'in relation to the forward momentum of the bike' it is not spinning backwards, -the tyre is independent of the bike in that it doesn't care what the bike's doing... so no matter how fast it is spinning it should still attempt to divert water to the outside of the tread... and it appears that the 'reversed' pattern isn't going to do that.

just my opinion, but I'm very interested to hear the real answer.

go to bed Nick.
 

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Discussion Starter · #16 ·
I'm a little drunk right now, but even though the tire has slowed down 'in relation to the forward momentum of the bike' it is not spinning backwards, -the tyre is independent of the bike in that it doesn't care what the bike's doing... so no matter how fast it is spinning it should still attempt to divert water to the outside of the tread... and it appears that the 'reversed' pattern isn't going to do that.

just my opinion, but I'm very interested to hear the real answer.

go to bed Nick.
Let me explain it this way. The part of the tire that is in contact with the pavement is stationary relative to the road surface. When the tire hydroplanes, it is no longer stationary relative to the road. So let's say the bike is moving at 55 mph. You hit a puddle that slows the front tire to 50 mph, while the bike remains at 55 mph. Now keeping the 5 mph difference, let's drop both speeds 50 mph. That would bring the bike to 5 mph and the tire to 0 mph. This would make the "reverse" tread come into effect. So you could look at it as a locked front tire sliding across the ground at 5 mph. Or you could drop the speeds 55 mph. Bringing the bike to 0 mph and the tire to -5 mph. Same principles apply.
 

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Look at the tire from the ground contact patch. It is siping the water away from the center.

From the top or front view you are actually looking at the tire "backwards" thus giving the illusion of rotating the wrong direction for water dissapation

The conti sport/road attacks I get questioned on alot as well, and the answer is the same.

If you have a loose tire hold it above your head and look at it, (as if you were the road)
 

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"Now, with a tire that has tread running the "right" direction: It would attempt to not hydroplane in the first place. However, if it did hydroplane, and the brakes were applied, the tread would pull water inward towards the center of the tire. As a result, the hydroplanning effect would be worsened."

The siping direction isn't going to make braking any better than normal rolling. If it is backwards it will always pull water into the middle of the tire, worsenuing any hydroplaning-unless you actually start rolling backwards.

Likewise when it is on correctly (siping diverting water away from the center of the tire) it will not get better or worse in relataion to speed or on the gas or on the brakes --(yes I know tbad brake application or too much power or too much lean in adverse condition will put you on your head-but that is due to traction limitations not the tires siping direction)as long as the tire is rotating forward it is still diverting water away from the contact patch
 

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It is due to the tire being turned sideways while cornering, not so much water diversion. Look at the front tire: if you turn/lean left, then the tread pattern suddenly makes sense. It is made to function while turning. Hydroplaning is not nearly as much an issue with motorcycles as cars, since the tires are not sitting flat on the road.
 

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Discussion Starter · #20 ·
Look at the tire from the ground contact patch. It is siping the water away from the center.

From the top or front view you are actually looking at the tire "backwards" thus giving the illusion of rotating the wrong direction for water dissapation

The conti sport/road attacks I get questioned on alot as well, and the answer is the same.If you have a loose tire hold it above your head and look at it, (as if you were the road)
Tread like this <<<<<<<< when looking from the top will look like this >>>>>>>> from the bottom. Say a tire with this <<<<<<<< on top is moving right to left across the computer screen. The point of the arrow will come into contact with the ground first, and push water outwards. The opposite is true for a tire with >>>>>>>> on top. It would pull water inward.

^^^ I understand this principle. :) And I understand why the rear tire tread runs the direction that it does.
 
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