Front tire wear question.....

[ctandc]

Okay....

So my old Kat is mainly a commuter...so I know that tires tend to wear a flat spot in the middle from lots of straight road riding...that I understand.

But the front tire on mine looks 'odd'....it's got a flat spot in the middle, but the flat spot is raised....and the tread is fine.


Any ideas?

I'll try to find the camera tonight...

[HS2020]

Sounds like the belts are starting to seperate in that area. Also the temps are changing and that will affect the tire wear also.

[Kfreak]

Too much air pressure? I know chit about tires. They are round and roll.

[Black_peter]

Sounds like it could be cupping.

[thetable]

For the record what tires are you running?

I would guess that you just have more wear on the sides, which makes the center look taller. Measure tread depth and go from there. If the center really is taller, and the tread depth is less in the middle than the sides, then HS2020 is most likely on the money. I know my tires tend to wear most on the sides, and the center usually still has a fair amount of tread depth left.

[StevieB]

You are living in a reversed universe. I am just suprised the rest of us can communicate with you...

[katman05]

Sounds like cupping, probably from running too low air pressure in the tire. Got a pic of this tire?

[ctandc]

Maybe it is 'cupping'..

Although the general consensus seems to be that cupping is caused by under inflation...and I check my tires at least every other day. I run 36 in the front and 38 in the rear.

Hard to get a good picture...

But here goes..

[thetable]

Looks like normal wear to me.

[md86]

I see no pic .....
But typically , bumps in the tire are cupping . Only belts I've ever seen snap were in cheap-*** Wal Mart tires on a car .

[GregS]

Where did you get the pressures for your tire? If they're the pressures from Suzuki for the standard tire then you are running the wrong pressures. Check with the manufacturer of your tire for specs appropriate for your bike.

[The CyberPoet]

I'm seeing a minor bit of excess wear on the left side of center, probably primary from the roads you ride regularly/repeatedly being heavily arched for drainage (from the looks of it), or you being far more aggressive in your left-turns than your right-turns. I definitely do not see any cupping or other indications of under-pressured operation...

Cheers,
=-= The CyberPoet

______________________
CyberPoet's KR Specials
Suzuki Stratosphere - 6 Cylinders, the new Katana?
The Best Motorcycle Metal Billet Tire Valves in the World, plus lots of motorcycle & Katana (GSX600F / GSX750F) specific help files.

[thetable]

I'm seeing a minor bit of excess wear on the left side of center, probably primary from the roads you ride regularly/repeatedly being heavily arched for drainage (from the looks of it), or you being far more aggressive in your left-turns than your right-turns.

I thought everyone had come to the conclusion that heavier wear on the left hand side is not caused so much by road crown, but because left turns are inherently longer.

My tires always have a bit more wear on the left and I am consistently faster through the right handers.

[The CyberPoet]

I thought everyone had come to the conclusion that heavier wear on the left hand side is not caused so much by road crown, but because left turns are inherently longer.

It depends heavily on the roads you ride and your riding style. Most places don't have all that heavy a crowning to the roads (say 6" between center & edge), but I've seen places in the USA where the crown is very heavily arched (say 18 - 24" or even more between center and edge). Often the problem is even worse in certain areas/certain roads in the grooves where the truck tires have worn the road down -- you don't want to ride in the center of the lane because of oil, tranny fluids, but if you ride in the tire grooves you tend to stick to one edge or the other because the center of the tire grooves aren't smooth, but rather rippled, and most bikers in the US tend to stick to the left side of whatever path they ride (left side of the lane, left side of the tire groove, etc.).
If your route consists of the same 10 or 30 mile ride to/from work with heavy crowning or bad tire rutting, and little alternative pathways, it could be partially down to the road-crown; the same issue is reported in the UK regularly on the opposite side, so I'm inclined to give it some credence...

My tires always have a bit more wear on the left and I am consistently faster through the right handers.

There's also the question of mid-corner corrections, length of arc of travel... Most riders (in the countries with drive-right rules) sweep left far longer than their right-hand turns, and tend to shed speed for tight rights, while tending to try to keep up speed to move through a left turn

For all I know, ctandc has a front end that tracks a little off from a bad fork seal or previous drop by a previous owner, (or he sits slightly lopsided on his bike, or has an unbalanced bike in some other sense, such as extra equipment under one fairing) that causes him to push more to the left than the right. Or it could be as simple as his daily journeys involve long left hand sweepers, but stop signs for all his right turns... I don't have a concrete answer other than I can't see any defects in the tire from the pictures that are indicative of under-pressurization or running too hot (same basic concept). A sideways picture showing the trailing edge of each treadblock compared to the leading edge of the next treadblock might reveal something that I can't spot from the existing pictures...

Here are some examples of bad tires, the pics of which I keep on my servers for this kind of discussion (originals provided courtesy of a KP/KR rider back in '05):

Scalloping & dry-rot/heat-rot:
Note how the leading edge of the treadblock is lower than the trailing edge of the previous treadblock


Same tire from above, showing cupping in the center areas (and the same dry-rot/heat-rot):


Cheers,
=-= The CyberPoet

______________________
CyberPoet's KR Specials
Suzuki Stratosphere - 6 Cylinders, the new Katana?
The Best Motorcycle Metal Billet Tire Valves in the World, plus lots of motorcycle & Katana (GSX600F / GSX750F) specific help files.