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I'm having a BT-45 installed on the front of the wing tomorrow morning. Can someone explain to me why some members mount the tire backwards? I would think that the tread is designed to displace water most efficiently when mounted in the direction of travel, i.e., forward. What is the benefit of mounting it backwards?
 

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Here is something I copied off of Metzler's website:

When producing tires, the top cap is heated with an angle bump on the carcass. To prevent the detachment of the assembled edges the tire has to be mounted (concerning the main stress: acceleration force at the rear wheel or brake force at the front wheel) corresponding to the respective declaration.
Therefore the declaration of the driving direction at the tires� sidewall is a very important safety regard and has to be noticed absolute. It is not allowed to mount front tires at rear wheels.
In case you intend to mount a rear tire on a front wheel it has to be assembled contrary to the driving direction declaration (direction of the arrow at the tires� sidewall). Please observe the standards in your country. In any doubts we kindly ask you to consult your dealer.
 

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IronMan
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SOMEONE ON FORUM JUST PUT ON ON LAST WEEK AND SAID HE WAS GONNA LEAVE IT ON AT REG DIRECTION I GUESS WE'LL SEEEEEE :eek:4:
 

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When you turn a rear tire around for the front the tread is in the right direction for water shed, the other reason is explained below.

-------------------------------------------------------------------------------
Tires Directional Arrows Explained By Avon Tyres
Published by Cyril Huze August 23rd, 2009 in Builders, Editorial and Wheels.
Before we can talk about directional arrows you must first understand a bit about tread patterns.
There are many different tread patterns but there is one main reason to have any tread and that
is to disperse water. (dust, dirt)
A tread pattern can be designed to disperse more water by making it rotate in only one direction.
Thus, the need for directional arrows. The arrow tells you which way to mount a tire for maximum
water dispersal. Another, less apparent reason for directional arrows is the tread splice.
What is a tread splice? When a tire is manufactured the tread portion of the tire starts out as
a long flat strip. This strip is wrapped around the tire and the two ends are cut on an angle
so one end overlaps the other rather than having square cut ends.
This overlapping point or splice offers a bigger surface area to bond together, rather than the
small surface area provided by square cut ends. (Imagine gluing your fingertips together, as
opposed to gluing along the entire length of your fingers laid on top of each other. Like an
angled splice, the overlapping fingers result in a much stronger bond).
To further ensure the strength of this bond along the tread splice the directional arrow will show
you which way to mount the tire so that when the rider is “on the gas”; the acceleration force on
the rear tire is pressing the splice together, rather than peeling it back.
As for braking, 80 % of the braking should take place in the front on most bikes. Therefore, the
front tread splice is run in the opposite direction than that of the rear, so when the rider is on
the brakes, he’s not peeling the tread splice back.
If you are using a tire that has a directional arrow for rear rotation only and for some reason you
want to put it on the front, make sure it is rotating in the opposite direction so you don’t
aggravate the tread splice.
Avon Tyres.
http://www.cyrilhuzeblog.com/2009/08/23/tires-directional-arrows-explained-by-avon-tyres/
 

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When you turn a rear tire around for the front the tread is in the right direction for water shed, the other reason is explained below.

-------------------------------------------------------------------------------
Tires Directional Arrows Explained By Avon Tyres
Published by Cyril Huze August 23rd, 2009 in Builders, Editorial and Wheels.
Before we can talk about directional arrows you must first understand a bit about tread patterns.
There are many different tread patterns but there is one main reason to have any tread and that
is to disperse water. (dust, dirt)
A tread pattern can be designed to disperse more water by making it rotate in only one direction.
Thus, the need for directional arrows. The arrow tells you which way to mount a tire for maximum
water dispersal. Another, less apparent reason for directional arrows is the tread splice.
What is a tread splice? When a tire is manufactured the tread portion of the tire starts out as
a long flat strip. This strip is wrapped around the tire and the two ends are cut on an angle
so one end overlaps the other rather than having square cut ends.
This overlapping point or splice offers a bigger surface area to bond together, rather than the
small surface area provided by square cut ends. (Imagine gluing your fingertips together, as
opposed to gluing along the entire length of your fingers laid on top of each other. Like an
angled splice, the overlapping fingers result in a much stronger bond).
To further ensure the strength of this bond along the tread splice the directional arrow will show
you which way to mount the tire so that when the rider is “on the gas”; the acceleration force on
the rear tire is pressing the splice together, rather than peeling it back.
As for braking, 80 % of the braking should take place in the front on most bikes. Therefore, the
front tread splice is run in the opposite direction than that of the rear, so when the rider is on
the brakes, he’s not peeling the tread splice back.
If you are using a tire that has a directional arrow for rear rotation only and for some reason you
want to put it on the front, make sure it is rotating in the opposite direction so you don’t
aggravate the tread splice.
Avon Tyres.
http://www.cyrilhuzeblog.com/2009/08/23/tires-directional-arrows-explained-by-avon-tyres/
I don't believe one word of his story about tread direction and water dispersal. Many motorcycle front tires run a tread pattern contrary to the tread pattern on a rear tire. If there were a substantial difference in wet weather performance one way vs. the other, you'd think they would would make them the same because tire companies don't like getting sued. I still see front tires with "backwards" looking tread so I don't believe it makes enough difference to worry about.

When doing research on hydroplaning I found several formula's used to predict at what speed a tire might hydroplane. NASA uses a formula to calculate when an airplane tire may hydroplane and it doesn't take into account the tire's tread. In fact none of the formula I found took tread into account.

Who is Cyril Huze? Is he a tire engineer working for Avon? No, a quick search for him on the internet revealed that he is a custom bike builder. Probably doesn't know anymore about tires than most of the people on this BBS.

Run your tires forward or reverse as you see fit. I am convinced it makes so little difference as to be ignored. But, if you run a rear tire on the front and turn it around backwards, the tread direction will be oriented similar to many other tires that are designated as front tires. Have fun with it.
MM
 

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bt-45 on front

I mounted mine frontwards and ran it 19K. Took it off cause I was tired of looking at it. I don't think it would have ever worn out. The sides were just starting to cup a little. With a new one costing 98. shipped to my door, it was a no brainer. Enjoy the tire.
 

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I don't believe one word of his story about tread direction and water dispersal. Many motorcycle front tires run a tread pattern contrary to the tread pattern on a rear tire. If there were a substantial difference in wet weather performance one way vs. the other, you'd think they would would make them the same because tire companies don't like getting sued. I still see front tires with "backwards" looking tread so I don't believe it makes enough difference to worry about.

When doing research on hydroplaning I found several formula's used to predict at what speed a tire might hydroplane. NASA uses a formula to calculate when an airplane tire may hydroplane and it doesn't take into account the tire's tread. In fact none of the formula I found took tread into account.

Who is Cyril Huze? Is he a tire engineer working for Avon? No, a quick search for him on the internet revealed that he is a custom bike builder. Probably doesn't know anymore about tires than most of the people on this BBS.

Run your tires forward or reverse as you see fit. I am convinced it makes so little difference as to be ignored. But, if you run a rear tire on the front and turn it around backwards, the tread direction will be oriented similar to many other tires that are designated as front tires. Have fun with it.
MM
Probably he really doesn't know that much about tires and the construction, he just published the information,,,:shrug: but how does it explain why some tire manufactures still put directional arrows on some tires that will fit other applications as a front tire <-- Rear Front --> if there wasn't something to it. Case in point is the tire that I have on the front of my Yamaha,,, the photo is below



The sipe ( tread ) pattern should be easily seen also in the next two photos. The first is a regular ME-880 on the front mounted in the right rotation of course. The next under it is a MPA Michelin Pilot Active ( rear tire mounted reverse direction ) It isn't hard to see that the sipes/tread pattern is Generally the same direction, and orentation.......


 

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Discussion Starter #8
Tire is mounted

Got the tire mounted in the forward direction. Smooth as a baby's butt. No wobble. I like it.
 

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KJ5IX,
You made my point about tread orientation better than I did :thumbup:. It's true, one picture is worth a thousand words. You said it all in three pictures.
MM
 
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