Tyre direction / tread pattern ?
Discussion
I've just had a set of Dunlop Qualifiers RR fitted to my Tuono, refitted the front wheel (obviously without checking the arrow for rotation!) the wrong way round.
If you think of the tread pattern as being an arrow head I would normally expect the point to meet the road first so that water is forced out to the edge of the tyre (which is what happens with the rear).
This tyre is the other way around, the tread pattern at the edge of the tyre meets the road first, which looks like it would then force water back towards the centre of the tyre.
Tyres look like this http://www.dunlopmotorcycle.co.uk/tyres/ranges/roa...
Anybody know why this is?
If you think of the tread pattern as being an arrow head I would normally expect the point to meet the road first so that water is forced out to the edge of the tyre (which is what happens with the rear).
This tyre is the other way around, the tread pattern at the edge of the tyre meets the road first, which looks like it would then force water back towards the centre of the tyre.
Tyres look like this http://www.dunlopmotorcycle.co.uk/tyres/ranges/roa...
Anybody know why this is?
I think the theory is that the front tyre exerts a braking (and therefore rearwards force). For that reason the tread pattern is reversed because the ford is in the opposite direction.
However the direction of rotation is still the Same so I would expect the tread pattern to point in the same direction.
I've never been able to figure it out. Still a puzzler. Its the same on my power road 2cts
However the direction of rotation is still the Same so I would expect the tread pattern to point in the same direction.
I've never been able to figure it out. Still a puzzler. Its the same on my power road 2cts
Hi, I'm from Dunlop motorcycle tyres and I hope what follows explains why front and rear tread patterns are in opposite directions to each other. Brummmie and mojitomax have got the right idea but this is the full expanation.
Tread patterns have several other duties other than evacuating water. One of which is to contribute to even-tread-wear characteristics, i.e. not wear out in a stepped manner that can affect a bike's handling towards the end of the tyre's life.
In order to give smooth, even wear the tread grooves need to be aligned with the forces acting upon the tyre. With the rear tyre the forces are accelerative (from the engine) and cornering. The further the bike is leaned over the less effect the accelerative forces have because the amount you're on the gas reduces as lean angles increase. But as the bike is leaned further over the more the cornering forces come into effect.
So in the centre of the tyre the grooves tend to be more circumferential in order to align them with the accelerative forces pushing the bike forwards at more upright angles. But the grooves gradually arc outwards towards the tyre's shoulders as the cornering forces come increasingly into play. Hence, even though most tyre tread designs differ from each other you will usually find large elements of arcing tread design. And those tyres that don't follow this principle tend to have poorer wear characteristics.
Because bikes are not 2-wheel-drive vehicles, the forces acting upon a front tyre are not accelerative and cornering but braking and cornering. Braking forces affect a rear tyre a little but they are overwhelmed by the accelerative forces. The vast majority of the bike's braking is done by the front tyre and braking forces are in the opposite direction to accelerative forces so in order the align the tread grooves with these forces from upright to leaned over they need to be in the opposite direction to rear tyre tread grooves.
This principle holds true for all of our road and race radial tyres: Roadsmart, Qualifier, Qualifier II, Qualifier RR, GPR Alpha-10, GP Racer D209 and D211GP.
If it's the thought of poor water evacuation that's concerning you, don't worry. When it's raining, research with our development riders has found that on the road, riders rarely lean beyond 28 degrees. 25 to 30 degrees being the usual range, depending on the rider's experience and riding style. So the grooves that clear the majority of the water are concentrated in this zone of the tyre and you'll notice that the grooves in this area of your tyres are largely circumferential on both front and rear, so no problems with water evacuation straight out from the rear of the tyre's contact patch.
New developments in compounding are also having a greater effect on a tyre's wet road grip. The Qualifier RR has as much wet road grip as all-round sports-touring tyres of just a few years ago, despite having far less tread grooves.
When the road dries out you use bigger lean angles so we reduce the amount of grooves further out towards the shoulders, where there is reduced need for water clearance. By having less grooves on the tyre's shoulders, and hence more rubber in contact with the road, dry road grip is increased.
I hope that helps.
Tread patterns have several other duties other than evacuating water. One of which is to contribute to even-tread-wear characteristics, i.e. not wear out in a stepped manner that can affect a bike's handling towards the end of the tyre's life.
In order to give smooth, even wear the tread grooves need to be aligned with the forces acting upon the tyre. With the rear tyre the forces are accelerative (from the engine) and cornering. The further the bike is leaned over the less effect the accelerative forces have because the amount you're on the gas reduces as lean angles increase. But as the bike is leaned further over the more the cornering forces come into effect.
So in the centre of the tyre the grooves tend to be more circumferential in order to align them with the accelerative forces pushing the bike forwards at more upright angles. But the grooves gradually arc outwards towards the tyre's shoulders as the cornering forces come increasingly into play. Hence, even though most tyre tread designs differ from each other you will usually find large elements of arcing tread design. And those tyres that don't follow this principle tend to have poorer wear characteristics.
Because bikes are not 2-wheel-drive vehicles, the forces acting upon a front tyre are not accelerative and cornering but braking and cornering. Braking forces affect a rear tyre a little but they are overwhelmed by the accelerative forces. The vast majority of the bike's braking is done by the front tyre and braking forces are in the opposite direction to accelerative forces so in order the align the tread grooves with these forces from upright to leaned over they need to be in the opposite direction to rear tyre tread grooves.
This principle holds true for all of our road and race radial tyres: Roadsmart, Qualifier, Qualifier II, Qualifier RR, GPR Alpha-10, GP Racer D209 and D211GP.
If it's the thought of poor water evacuation that's concerning you, don't worry. When it's raining, research with our development riders has found that on the road, riders rarely lean beyond 28 degrees. 25 to 30 degrees being the usual range, depending on the rider's experience and riding style. So the grooves that clear the majority of the water are concentrated in this zone of the tyre and you'll notice that the grooves in this area of your tyres are largely circumferential on both front and rear, so no problems with water evacuation straight out from the rear of the tyre's contact patch.
New developments in compounding are also having a greater effect on a tyre's wet road grip. The Qualifier RR has as much wet road grip as all-round sports-touring tyres of just a few years ago, despite having far less tread grooves.
When the road dries out you use bigger lean angles so we reduce the amount of grooves further out towards the shoulders, where there is reduced need for water clearance. By having less grooves on the tyre's shoulders, and hence more rubber in contact with the road, dry road grip is increased.
I hope that helps.
Just purchased a front tire Dunlop Sportmax Qualifier and the directional side arrow is opposite to the bottom of the "V"s at the tire road contact and that means that the water will be pushed to the middle. Will DUNLOP be so kind to direct me to a manual for education of H2O, in perfect accordance with their standards for riding forward and breaking ?
Mack Ratza said:
Just purchased a front tire Dunlop Sportmax Qualifier and the directional side arrow is opposite to the bottom of the "V"s at the tire road contact and that means that the water will be pushed to the middle. Will DUNLOP be so kind to direct me to a manual for education of H2O, in perfect accordance with their standards for riding forward and breaking ?
Firstly this thread is nine years old.Secondly a detailed answer to the exact question you are asking was provided by the tyre manufacturer six posts up from yours.
Mack Ratza said:
Just purchased a front tire Dunlop Sportmax Qualifier and the directional side arrow is opposite to the bottom of the "V"s at the tire road contact and that means that the water will be pushed to the middle. Will DUNLOP be so kind to direct me to a manual for education of H2O, in perfect accordance with their standards for riding forward and breaking ?
Yes, if only Dunlop themselves had taken the time to come on here and post a detailed answer to your question... 
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