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Front tyre tread...

Discussion in 'Technical and Troubleshooting Torque' started by Sweeris, Jul 2, 2008.

  1. I have been wondering for some time about the tread on the tyres. I know that the tread for the tyre are suppose to channel out from the middle to the side of the tyre. I have looked at a few front tyres fitted and the tread seem to be the wrong way around. On those bikes I have checked the direction of rotation and it is correct but the tread looks like it's backwards. It just doesnt seem right for the tyre to channel water into the middle...

    I have asked this in the last spanner night and no has the answer to it.

    I'm abit confussed, can anyone decribe/explain how this works??
  2. very roughly, and in simple terms;

    direction of travel ---->
    rear tread >>>
    front tread <<<

    this is because the most basic rotational force applied to the road, for a rear tyre is applying power (think of it grabbing the road and forcing it backwards, to move you forwards) whereas the front is designed grab the road, resisting the movement of the bike forwards, when you apply brakes.

    the channels are meant to "pump" the water out, by the resulting deformation of the rubber, when these forces are applied. This happens because the channels are stretched and therefore constricted within the contact patch as the force (braking or accelerating) is applied, which then squeezes the water towards a part of the tyre where the channels are wider.

    so, it would be reasonable to assume that the channels would differ in general direction from front to rear.
  3. Do you mean
    direction of travel ---->
    rear tread >>> At contact with road or
    rear tread >>> When viewed from the top of the wheel?
  4. my original diagram shows it looking at the top of the wheel, which is probably a poor representation on my part. :oops:

    but yeah, i think you get what i meant.
    keep in mind, this is very generalised, and tyre companies have proprietary treads which will differ from this :)
  5. Yup mine is like
    direction of travel ---->
    rear tread >>>
    front tread <<<
    when viewed from the top.

    Some go like
    direction of travel ---->
    rear tread >>>
    front tread >>>
    So I'm wondering whats the difference there. Like I understand the grip part with my front but where is the water gonna go? Wont it just hydroplane since the water goes towards the middle,no?

    edit: I think I understand now after reading it more carefully. Thanks for the info...
  6. It's because in that at least a portion of a carcass line extending radially out from the maximum width position in a carcass line of a tyre is configured so as to subtantially conform to an equilibrium carcass line expressed by the following equations (1) and (2) calculated by using an internal pressure allotment ratio g(y) of a carcass layer at the tread portion that is obtained by setting the distributional configuration index α of the following equation (3) at 4 or more, and that a tread pattern having a direction property is provided to the tread surface thereof, wherein: yD ≦ y ≦ yA, & in yB ≦ y ≦ yD, provided that a line drawn vertically down from the center of the tread portion to the axle of the tyre is y axis of coordinates with the axis of the tyre being z axis of coordinates, r1, yA, yD, yC, yB and η denote as follows:
    radius of curvature of the equilibrium carcass line;
    y axis of coordinates for the carcass line at the center of the tread portion;
    y axis of coordinates for the carcass line at the effective width end portion of the belt layer;
    y axis of coordinates for the carcass line at the maximum width position in a tire carcass line;
    y axis of coordinates for the carcass line at the bead portion; and
    η :
    the internal pressure allotment ratio of the carcass layer at the center of the tread portion.
  7. cut & pasted from here ;)
  8. Well fcuk me, that clears things up. Why did you not just say that at the beginning?!
  9. :LOL:
    i dont think he even knew what he wrote.
  10. Nice av ipic - but I'll miss the little stabby guy :(
  11. [​IMG]
    here he is :)
  12. Not wrong there. I used to get a quadratic equation right though... once every blue moon.

    My maths teacher in year ten knew I was so hopeles, he banned me from entering his class rooms.
  13. My thinking too when I read it. :LOL:

  14. Next lesson will be nuclear physics.

    WTF was that!!!!!!!