Whats going on with my front tire??

[offcamber]

Noticed this today...its like this all around the tire in the same pattern??

I don't notice any vibration or odd handling...

 

[avc8130]

Yup, that happens.

From: http://www.rattlebars.com/tirewear/index.html

CUPPING:
Cupping, which is more accurately described as scalloping (see pictures, but we will use the more common term "cupping" here), 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 (thank you for that Mr. Tire!). 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 one banks into a turn. Upon examination of the pictures at left of our sample rear Avon, our dusted front VTX Dunlop D256, and the picture of our chalked Dunlop D206 one can see how the cupping follows the tread pattern. 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. As one can see, the simple tread pattern of the Avon pictured produces a simpler scallop pattern while the more complex VTX D256 Dunlop is somewhat involved, though still easily seen in our photo. Cupping on the Valkyrie Dunlop D206 is very hard to photograph because of the complex tread pattern. 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.

The following textual illustration comes from Martin who contributed to this article by E-mail on June 26, 2006:
I was just reading your bit on "cupping" and thought I'd share with you how I describe what's going on. I usually tell people that what's happening is that the individual "blocks" or "islands" of tread are squirming and deforming due to the forces applied to them during cornering and braking. When this deforming takes place, the wear is naturally not evenly distributed across the surface of the tread. (I define a tread block as an area of the tire surface surrounded by a groove.) I next tell people they can demonstrate to themselves what's happening by taking a new pencil with an unused eraser on the end and while holding the pencil perfectly vertical, push down and drag the eraser on a rough surface in one direction. Then I tell them to look at the eraser and note that all the wear is on the leading edge and not evenly distributed across the end surface of the eraser. It seems to make the concept easier for many to understand. Cheers!

ac

 

[sportsguy]

So...

what tires?
how many miles?

 

[offcamber]

Battlewings.... 4700 Miles

 

[OldRider]

Straight line running and not many curves is my guess ????

 

[offcamber]

Straight line running and not many curves is my guess ????

I laugh when people say this. yeah your right I never turn, in fact if I am forced to turn I stop and slowly duck walk the bike so as to never have to lean the bike over :......


I commute some highway some back roads....the roads are what they are some have curves some don't. I turn about as much as anyone...no I am not peg dragger but I lean over plenty. Same when I ride for pleasure....some highway some back roads....I guess I'm suppose to weave constantly to keep this from happening.

 

[avc8130]

Battlewings.... 4700 Miles

Pretty much exactly the same as my experience.

I assume you rock the bike pretty good. You probably actually TURN a fair amount.

ac

 

[OldRider]

I laugh when people say this. yeah your right I never turn, in fact if I am forced to turn I stop and slowly duck walk the bike so as to never have to lean the bike over :......


I commute some highway some back roads....the roads are what they are some have curves some don't. I turn about as much as anyone...no I am not peg dragger but I lean over plenty. Same when I ride for pleasure....some highway some back roads....I guess I'm suppose to weave constantly to keep this from happening.

Well what I was thinking was that you took a trip without a lot of turns. I've rode out to CA. and back a few times the southern route and while running most of the way on the interstates I've always had cupped out flat in the center tires when I got back home. No offense meant.

 

[sportsguy]

air pressure?

 

[tomatocity]

air pressure?

Agree with sportsguy. Can't believe the discussion got this far without tire pressures being asked. Also is the sag set?

 

[Firefight911]

Agree with sportsguy. Can't believe the discussion got this far without tire pressures being asked. Also is the sag set?

No one wants to get yelled at for the search function or the last forty threads which all discussed these two things. I opened and closed the dialog reply box multiple times.

Bump it 2 psi and try again.

 

[offcamber]

I did a search but didn't find exactly what I was looking for.

running it at 30 PSI, Front suspension is at the factory setting I can bump it up to 33 and see what happens

 

[Firefight911]

Absolutely too low a pressure. Don't expect your bumping the pressure now to fix this tire's issue. It's too worn to correct it. Check the rear's pressure as well along with the suspension.

"Factory" setting on suspension is for a person approximately 180-185 lbs. The only proper setting of a suspension comes from manually doing the set up and measuring the data. It's easy and will transform any motorcycle in just a few short minutes of work with a friend.

 

[tomatocity]

Start at 36F 40R.

Factory settings will give you a negative sag or less weight on the front tire. The Tenere likes weight on the front tire.

 

[CDMartin884]

The way roads are crowned will also have a bearing on cupping. I live in Florida, and mine have always cupped and wore the same, no matter what bike, brand of tire, and they show usually around the 4.5K mark, then go down hill pretty quick. Metzler's, Michilen's, Avon's, Bridgestone's, etc. With the exceptions of my K60's, But they have 8K on them right now, and 6K were from out west in less than 3 weeks. Other than the typical squared rear from slabbing interstate, they're doing great. I run 36 PSI front & rear on the K60's, which is lower than on street tires I have had in the past.

 

[Firefight911]

The K60s are max pressure of 36. You can't compare pressures from tire to tire apples to apples. My Karoo are 36 max where my Anakee 3 are max 42 front and 41 rear. What you run is objective to start (manufacturer suggested) and subjective after that. Always starting with a correctly set suspension first.


Sent from my iPhone using Tapatalk which means there are more than likely spelling errors!

 

[CDMartin884]

I thought that was pretty obvious, it was statement of psi and not a comparison. The compound a tire is made from with the proper psi to weight is more important than suspension set up. While suspension and riding style are factors to tire longevity, there are many more than just those.