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This applies to car tyres
too.
All tyres manufactured for
USA & Europe have to show a DOT (Dept. of Transport)
code. That's for quality control, from the code they
can trace any tyre back to factory, machine, mould tool,
batch etc. which is good for a product recall.
Within that code look for the 3 or 4 number sequence.
They're normally easy to spot, being in a small oval
separate from other numbers because they have to keep
changing them. The first two are the week, the other's
the year.
A tyre made in the 1980's
will have something like DOT 108 That's the 10th week
of 1988.
A tyre made in the 1990's will have something like DOT
028
That's the 2nd week of 1998
A tyre made in the 2000's will have something like DOT
2700 That's the 27th week of 2000
So, 3 numbers and no
it's '80's ! (yes I've seen them still fitted), 3 numbers
and there are 's
it'll be '90's, 4 numbers is 2000's.
Now, remember the compound
"goes off", the recommended life of a tyre
is only 6 years (2yrs shelf life if stored properly
and 4 years on the bike). Those super-sticky's with
good tread, on that bike you're buying might actually
offer little grip. They might have died years ago.
Ride safe Oz.
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Not as daft as it sounds.
Make sure the tyre is fitted with the direction arrow
(it's on the sidewall) facing into the wheel's rotation
when on the bike. We've seen too many fitted the wrong
way round, the fitter should mark the wheel before removing
the old tyre. If put on wrong the result can be lethal,
the tyre carcass will fail very quickly.
Around the tyre there'll
normally be a line, so the fitter can check it's evenly
seated on the bead. Check it, they don't always seat
properly first time.
Check your tyre pressure
and re-check daily for the first week, a newly fitted
tyre tends to lose air around the bead until it's settled
down. After that, you go back to checking on a weekly
basis. Get an accurate gauge, and check the pressure
when cold. Remember, even a couple of pounds can make
a lot of difference to a bike's handling and fuel consumption.
With a new tyre, run it in
at least for the first 100 miles. Tyres actually grow
(another reason for the pressure to drop) and shape
themselves on the rim. Gently increase lean angles,
new tyres are shiny (it's the mould release wax and
it's slippy), why not use some sandpaper then.
Especially with the rear
on a powerful bike, again take it easy for a while.
The fitter will have soaped the rim before fitting the
tyre. 100 brake horsepower sir ? that'll turn the tyre
on the rim which makes balancing it a bit of a waste
then.
Ozzy.
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Well apart from the info
on tyre fitting (which includes a bit about running
it in) here's something that may be new to you :-
What's a tyre made of ? You may be surprised to learn
that the biggest single components of tyre rubber are
oil and graphite, both are lubricants. It's not actually
made of rubber, that's a myth. It's man-made (that's
what the vulcanising process was about and incidentally
why disposal is a problem), for us the problem's more
immediate.
All oils are made up of lighter and heavier elements.
If you subject a new tyre to excessive heat (that's
100 bhp at the rear wheel sir) you can "sweat"
out the lighter oils. That'll degrade your tyre, so
it won't last long but that won't matter because if
you sweat oil across your tyre then you won't be on
it for long anyway. That's another reason to run-in
your new tyre, it'll keep your arse off the road.
Oz.
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Don't have the tube repaired,
it's not worth it and the failure can be too sudden
to keep control. Fit a new tube, they're cheap enough.
A lot of people (and tyre
shops) will simply fit a new tube. The tyre needs repairing
too, just as a tubeless tyre would be, 'cos there's
a hole in it. In use, water and muck will get squeezed
through the hole and abrade between the tyre and tube.
It'll fail again so have the tyre repaired as well.
Have it re-balanced, that patch and new tube will have
changed the balance. Oz.
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Tyre pressures are normally
quoted for an only 10 stone (140 lb./ 65kg) solo rider
and are considered ok for + or - 10kg. So if you're
over 11 ½ stone (that's most of us then) you
will need to study the handbook. If you can't get good
info on this, try slightly raising the pressures by
up to 3psi but keep the same differential between front
and rear. Oz.
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