• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Front tire "cupping"

  • Thread starter Thread starter Anonymous
  • Start date Start date
A

Anonymous

Guest
I was reading in this magizine that on this old bike the front tire was "cupped" and he had to replace it. Is that like cracked or worn?
 
It's also sometimes called 'scalloped' where one side of a tread block,usually leading or trailing edge, is worn more than the rest of the block,and can be caused by the tire being out of balance, misaligned, out of round, or from an ineffective shock absorber, which may allow the wheel to bounce erratically or uncontrollably
 
Out of balance, out of round, that bounciness when you're on a smooth road and can't figure out where the bumps are coming from. caused the tire to wear unevenly. It is easy to spot on a car tire.
 
I've known blokes who had head stem bearings replaced , bought
fork braces,invested in steering dampeners , all for the sake of a buggered front tyre !! :lol: :roll:

cheers Katana
 
Cupping can be a characteristic of some tyres, but it can be caused by front suspension setup making the tryre do too much of the work that the suspension should
 
saaz said:
Cupping can be a characteristic of some tyres, but it can be caused by front suspension setup making the tryre do too much of the work that the suspension should
Click to expand...

The dunlop F-24 is bad about wearing unevenly,I had one on my 1000g and it "cupped", my zn1300 voyager had a F-24 on it when I got it, and it was cupped, a coworker of mine has a Hardly ableson and has a F-24 on it, and it to is cupped.

I now have a chin shin "highmax" on the 1000g and it is wearing evenly, on the zn 1300 I put a dunlop cruisemax on it and it is wearing even.
 
Don't know about front tire cupping, but statistical analysis of beer-drinking GSR forum participants shows that they are "in their cups" most of the time. :D
 
Simon Waters said:
Don't know about front tire cupping, but statistical analysis of beer-drinking GSR forum participants shows that they are "in their cups" most of the time. :D
Click to expand...

Cute, Simon.
One of those adopted terms that works for both sexes, even if the women don't drink beer. :wink: :roll:
 
Increased tire pressure is supposed to help reduce the development of cupping, but I don't have factual data to support this. I always thought it was from uneven wear due to the distortion subjected by loading. I've had street tires at the drag strip wear more on the leading edge than the trailing edge of the block because under hard acceleration it was deformed this way. Similarly I've had front tires that I used alot of brakes on that wore more on the trailing edge than the leading edge. Picture how the tread looks if you could freeze it under load and look at it from beneath a clear glass road surface. This probably represents the wear we see. Many bikes with fairings added to them seem to be hard on front tires as well; don't know if its the weight, the increased load due to wind resistance or both. As stated earlier though, this can also be caused by improper condition of other components on the bike....something bent, out of adjustment, out of balance, etc.
 
assakins said"Increased tire pressure is supposed to help reduce the development of cupping,"

wouldn't increased tyre pressure lead to decreasing grip If you already have tyres at optimum pressure ( not the max. pressure on tyre wall)

cheers katana
 
The purpose of the increased pressure was to "stiffen" the tire and reduce distortion of the carcass under load, hence reducing uneven block wear. Makes sense intuitively. Also passes more of the forces onto the suspension and further.
 
So I take from that, the pressure added is minimal so as not to be adverse to the handling of the bike?


katana
 
Cupping of a tire can be caused by poor shock absorbtion. Fork oil has water in it, unequal fork oil hieghts, old oil, broken spring, weak spring, not enough air, too much air.....
too many to list.
Check into the rebound and damping rate of the fork, it could be the culprit.
 
You must log in or register to reply here.
Back
Top