Jeff Cawthorne wrote:
>
> >2) They are directional. Run the L tire on the R side and note the
> >delamination line that forms. Kumho claims it is ok. But it is a bit
> >scary to see what appears to be a perfectly straight knife cut from one
> >side to the other.
>
> This is where I have to correct you. They aren't directional, you can run
> them backwards and on the wrong sides of the car, and they will be just as
> fast. I have just recently turned mine inside out, due to excessive
> scalloping from the San Bernardino Pro. My Vette pushes quite a bit and
> rolls the edges over, so once the blocks wear down, I turn them around. I
> have done this on every set that I have had so far, and haven't noticed any
> ill effects. The mold cracks are normal, and yes they are a little
> disturbing to see. They don't always appear though. My last set didn't do
> it at all, and my current set, three of the four are cracked.
You can try to correct me all you like, but they were _designed_ to be
directional - hence the L and R on each and every tire. The fact that
you can run them contrary to their intended design does not obviate
this. However, at some stage last year Kumho apparently decided to not
bother with making both tires. I heard that it was due to an excess of L
tires, and I also heard they found out through actual experimentation
that it didn't seem to matter. But for whatever reason, they did so
after the fact.
The 'cut' that I am referring to as a delamination has only occurred on
_my_ tires on the ones that are marked L but were run on the R side of
the car. And I would not characterize this as a "mold crack". This is a
cut in the rubber in a perfectly straight line transverly across the
tire as though some has taken a scalpel and attempted to dissect it. It
appears to extend all the way to the cords.
I have not seen this happen (yet) to a left side tire that was marked as
a L. Did you notice if this also appeared in cases where the tire was
only run on the side as marked, or did it only appear on tires that were
run on the other or both sides?
Regards,
Paul Foster
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