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Front Tire Wear

Posted By: Rapala 50

Front Tire Wear - 11/10/17 02:11 PM

[Linked Image]
Any idea why the tread on the left side of the tire is wearing the way it is,, tire has 9500 miles , same thing happened on the one before this. Bike has 53k, Tire is pilot road 4
Posted By: dirtrider

Re: Front Tire Wear - 11/10/17 02:29 PM

Originally Posted by Rapala 50

Any idea why the tread on the left side of the tire is wearing the way it is,, tire has 9500 miles , same thing happened on the one before this. Bike has 53k, Tire is pilot road 4


Morning Rapala 50

Yes, I have a good idea!

If you get some help then lean the bike over so the center of that wear spot is flat on the pavement you can then determine what you were doing with the bike to cause that wear. (hint-- left hand turns & left hand corners)-- Left hand corners & curves are usually longer & ridden faster than the same turn or corner turning to the right.

Thing to keep in mind is: the area of that tire that is worn MUST be touching the pavement for it to wear like that. So with wear that far off center it is doubtful that you are touching that part of the tire while riding straight ahead even if leaning the bike slightly to counter PTTR.
Posted By: Dennis Andress

Re: Front Tire Wear - 11/10/17 04:26 PM

Such wear was common in BMW bikes made 10-15 years ago. Both of our K1200 RSs did it. I assumed it happened because the rear wheel is offset a bit. Put the bike on the center stand and use some string to check me on that.

The wear sucks. Especially if lane splitting is part of your day. The off center wear would catch the asphalt seam where the lanes meet and yank the front wheel into the seam. We have a habit of checking the roundness of the front tire, looking for that off center high spot, and replacing both tires as when we notice it.

9500 miles on a tire is above average. 6K is average for us, so I'd expect the slow bikes to get 7-8K, tops.
Posted By: lkraus

Re: Front Tire Wear - 11/10/17 04:44 PM

Additionally, the side tread compound is softer than the center tread.
[Linked Image]

That tire was probably past the wear indicators about 2000 miles ago. I hope you are not riding on it any more.
Posted By: gkiesel

Re: Front Tire Wear - 11/15/17 08:35 PM

It was always explained to me to be in part the crown in the road. i ride alot of back roads that are oil and chip which is very abrasive. Most front tires wear out on the left regardless of the brand of machine I have owned.
Posted By: bwpsg42

Re: Front Tire Wear - 11/16/17 02:06 PM

riding a distance with a stiff crosswind can aggravate wear as well especially if compounded with the crown in the road. I rode across Oklahoma with a stiff north wind one day a many years ago on a 96 RS and basically ground off the left side of my front tire which was almost new when I started in New Mexico.
Posted By: dirtrider

Re: Front Tire Wear - 11/16/17 04:47 PM

Morning gkiesel, bwpsg42

The OP's picture isn't showing now but when it was the wear was WAY off-center way too far off-center to be road crown or cross winds.

As I mentioned above, If the tire part that is worn is not touching the pavement then it isn't (can't be) wearing. If the OP was riding on a road with a crown that severe, or in a cross wind that he had the bike layed WAY WAY over then I do believe he would have rememberd that.

That is why I have the rider get help & lay the bike over until the tire wear spot is flat on the pavement as THAT is lean angle he was at to cause that wear.
Posted By: EyeBike528

Re: Front Tire Wear - 11/27/17 01:57 AM

Funny thing, my wife just pointed out the whole 'crown of the road' explanation thing she discovered on Quora.
It is because the center of the highway is higher to promote drainage of water down at the sides. In the US we ride on the right side of the road, therefore the crown is to our left, and is the highest point on the road and causes in-even wear. If we lived in Europe and rode on the left side of the road, well then, there would be greater wear on the right side of the front tire instead!.
Here's the link and a diagram: https://www.quora.com/Why-do-my-motorcycle-tires-have-uneven-wear
After 8 thousand miles in the past 2 years, it's why I need a new front time!
Jim S.
Posted By: dirtrider

Re: Front Tire Wear - 11/27/17 11:54 AM

Originally Posted by EyeBike528
Funny thing, my wife just pointed out the whole 'crown of the road' explanation thing she discovered on Quora.
It is because the center of the highway is higher to promote drainage of water down at the sides. In the US we ride on the right side of the road, therefore the crown is to our left, and is the highest point on the road and causes in-even wear. If we lived in Europe and rode on the left side of the road, well then, there would be greater wear on the right side of the front tire instead!.
Here's the link and a diagram: https://www.quora.com/Why-do-my-motorcycle-tires-have-uneven-wear
After 8 thousand miles in the past 2 years, it's why I need a new front time!
Jim S.


Morning EyeBike528

On that site I see turns mentioned as the cause, I see road crown mentioned as the cause, I see wedging mentioned as the cause, I see rim alignment mentioned as the cause but no data, testing, or explanation proving that any one of those are the actual cause of L/H side motorcycle wear.

I guess common sense makes me ask how a typical U.S. road crown of 1°-2° can cause front tire wear that is 10°+ off center?

How can road crown wear a tire that far off center on a single track vehicle?

Again, lean the bike over until the part of the tire that is wearing is flat on the pavement, that is how the bike was ridden to cause the wear in that area.

Even leaning the bike over until the tire wear area is on the pavement on a 2° crowned road will show normal riding on that crowned road won’t get it anywhere near the tire wear spot shown in the OP’s post above.
Posted By: Dimond

Re: Front Tire Wear - 12/03/17 01:07 PM

I can't see the photo and I know little about tire wear. But will that stop me from offering an opinion? NO!
I wear out at least two sets of PR4 (NOT PR4GT) each year. I run front at 36psi and rear at 42 psi ALWAYS. I love my PR4s - they stick well and are awesome in the rain (did a track day in heavy rain with nary a slip). I HATED my P R4GTs, which Michelin prescribes for the RT - way too harsh a ride for me. The GT has a heavier side wall so less flex and can handle the FULLY LOADED weight of RT (the PR4 can not). However, since I weigh 165 pounds, never ride two up, don't carry side cases - my load is within the range a PR4 can handle. Went to a seminar couple of years ago by senior Michelin MC tire manager who also races AMA and took away a few key points: don't ever run BELOW recommended psi (a bit over ok but NOT lower); don't use lighter than recommended; and replace tires by time you get to wear bars; low air pressure accelerates wear on side (not center) of tire.

THOUGHTS ON OP:

1. Maybe running low psi?
2. Maybe overloading PR4s?
3. Maybe should use PR4GTs?
4. Maybe should replace tire before getting to wear bars?
5. Maybe should send specifics to Michelin for their feedback?
6. Maybe desired tire mileage is unrealistic?
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