Tire cupping

My front tire cupped when the fork tubes were skewed.

Kawickrice wrote:

Cupping on my truck was from bad shocks.

I would look at everything in the suspension. Roy

Vaguely recalling something from Dunlop about front tire cupping being related to using front brake.

Suspect pulsing during braking, due to warped disk, would hasten the cupping.

Good Luck!

Patton wrote:

Vaguely recalling something from Dunlop about front tire cupping being related to using front brake.

Suspect pulsing during braking, due to warped disk, would hasten the cupping.

Good Luck!

I remember my zx-9 having the same problem and if i remember correctly, one of my riding buddies at the time
saying something about braking in corners having something to do with it....the cupping was minimal, but you could feel it if you ran your hand over tire edge.....

Cupping, which is more accurately described as scalloping, is a natural wear pattern on motorcycle tires and it will always follow the tread pattern. It is not a sign that you have bad suspension parts. It merely shows that your tire is indeed gripping the road when you make turns.

This cupping develops within the side wear bands of a leaned motorcycle. The extreme forces that come in to play when the bike is leaned in a turn are what produce the effect and when the wear becomes sufficient, one will experience vibration and noise when they bank into a turn.

The leading edge of the tread does not flex much as it grips the road and the rubber is scuffed off the tire in that area causing a depression. As the tire rotates, the pressure moves to the trailing edge of the tread pattern where the tread flexes more causing less scuffing so less material is ground off the tire. The more complex the tread pattern, the more complex the cupping pattern will be. The softer the compound of the tire, the sooner this cupping will develop. Radial tires are more prone to cupping than are bias ply because the compound of radials is softer.

Low tire pressure will exacerbate this wear pattern and you will lose many serviceable miles by running low. Improper balance has nothing to do with cupping on a motorcycle tire. Improper balance will merely cause your bike to vibrate within certain specific speed ranges.

Cheers!

TeK9iNe wrote:

Cupping, which is more accurately described as scalloping, is a natural wear pattern on motorcycle tires and it will always follow the tread pattern. It is not a sign that you have bad suspension parts. It merely shows that your tire is indeed gripping the road when you make turns.

This cupping develops within the side wear bands of a leaned motorcycle. The extreme forces that come in to play when the bike is leaned in a turn are what produce the effect and when the wear becomes sufficient, one will experience vibration and noise when they bank into a turn.

The leading edge of the tread does not flex much as it grips the road and the rubber is scuffed off the tire in that area causing a depression. As the tire rotates, the pressure moves to the trailing edge of the tread pattern where the tread flexes more causing less scuffing so less material is ground off the tire. The more complex the tread pattern, the more complex the cupping pattern will be. The softer the compound of the tire, the sooner this cupping will develop. Radial tires are more prone to cupping than are bias ply because the compound of radials is softer.

Low tire pressure will exacerbate this wear pattern and you will lose many serviceable miles by running low. Improper balance has nothing to do with cupping on a motorcycle tire. Improper balance will merely cause your bike to vibrate within certain specific speed ranges.

Cheers!

Very interesting. Makes sense to me

TeK9iNe
Very good explanation. Thanks.
Where did u learn about that?

yes, thanks. I was going to write basically the same thing, but my writing skills are no good.:laugh: This question gets asked over and over and over again on every motorcycle newsgroup and it's just downright amazing what goofy ideas people have on the subject.

I never new what the cause was. this is new to me on the sides.i had it on the center before. i assume that was due to the tires being out of balance.
I just got an email back from the local bike shop and he said
"Usually its an air pressure issue or balance issue.
Most tires when worn will cup though."

As to reasons for cupping, here's a link with some illustrations to help explain the interaction between tire and road surface when braking or leaning.

w6rec.com/duane/bmw/cupping/index.htm

Good Luck!

My front tire also has cupping, but on the left side only.
I am using Bridgestone Spitfire tires.
I will be replacing both tires this Winter, and will keep a better eye on tire pressure this time.

Make sure you change your fork oil if the front is wearing on one side. Roy