Worn tyre, is it time to replace?

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jml
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Worn tyre, is it time to replace?

Postby jml » Tue Nov 18, 2014 4:41 pm

Hey all,

I've got a brand new Dunlop D803 on the rear and an unknown age tyre on the front (as pictured, click to open image then click to enlarge). On the weekend I completed my first trial =D> and was shocked to see how much the rear wheel wore down. This made me think it might not be optimal to have such an old front match with such a new rear. I currently have a brand new D803 front tyre in the shed but was reluctant to install it as I didn't know how "worn down" the front was. I cannot find a manufacturing date on the front, but it's got a bunch of hairline cracks appearing too. Apart from looking a little shabby, how much of a performance hit would I take leaving it on? Would there be some fighting rear/front with how new/sticky the rear is?

Many thanks!



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Re: Worn tyre, is it time to replace?

Postby David Lahey » Tue Nov 18, 2014 5:21 pm

jml wrote:Hey all,

I've got a brand new Dunlop D803 on the rear and an unknown age tyre on the front (as pictured, click to open image then click to enlarge). On the weekend I completed my first trial =D> and was shocked to see how much the rear wheel wore down. This made me think it might not be optimal to have such an old front match with such a new rear. I currently have a brand new D803 front tyre in the shed but was reluctant to install it as I didn't know how "worn down" the front was. I cannot find a manufacturing date on the front, but it's got a bunch of hairline cracks appearing too. Apart from looking a little shabby, how much of a performance hit would I take leaving it on? Would there be some fighting rear/front with how new/sticky the rear is?

Many thanks!

Rear tyres generally wear out much faster than fronts.
It's common for fronts to go hard due to age and still be barely worn by the time they are hard. Yours looks worn and hard and would probably be terrible on wet rocks compared with a new front. Different brands of front tyres go hard at different rates. Judging by the photos I'd say the front is 3 to 6 years old, if the bike was garaged in the dark, or might be newer if it has seen a lot of sunlight.
To answer you question no there is no fighting between front and rear even if the tyres are in very different condition. The front and rear do completely different things for the handling. If you only ever ride dry conditions a new tyre would make little difference except to the feel of the steering (the carcass goes hard and stiff which detracts from steering feel)


relax, nothing is under control

jml
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Re: Worn tyre, is it time to replace?

Postby jml » Tue Nov 18, 2014 7:30 pm

Thanks for the reply david, I'm going to replace the tyre this weekend for sure. Is there a good rule of thumb for replacing the front tyre? Maybe a certain number of trials? Maybe every season?



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Re: Worn tyre, is it time to replace?

Postby David Lahey » Tue Nov 18, 2014 8:08 pm

just compare the feel of the edges of the knobs on your tyre, trying to make a dent with your thumbnail and then try same thing on a new tyre to compare. Also try the knob twist test, gripping a knob between your thumb and index finger.
Knob twist is good for rears because they lose their knob edges pretty much immediately
I use these methods and find that fronts generally are OK for about 3 years if the bike is garaged in the dark.
Some people cut their rear tyre knobs to restore the edges. This is good for maintenance economy but not strictly within the rules.


relax, nothing is under control

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Gary B
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Re: Worn tyre, is it time to replace?

Postby Gary B » Wed Nov 19, 2014 7:11 pm

Just about all tyres have a manufacture date on them.
This is used on car tyres as well as motorcycle tyres.
They don't just have a normal date stamped on them.
It's a 4 digit code & mainly only on one side of the tyre.
eg: 2712 or 3511 this means the first example was made in week 27 of 2012, second example was made in week 35 of 2011.
Get it?
Brand new tyres may sit in the importers warehouse for ages & then on a bike shops shelf for even longer.
I think you would be very lucky to find a new Trials tyre in Australia with a manufacture date with 14 as the last two digits.


Gary B. from Wollongong MCC.
Now the Old Man in "Team Boniface"
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Re: Worn tyre, is it time to replace?

Postby eagle » Wed Nov 19, 2014 9:25 pm

Just checked a Mitas front tyre i bought 5113 pretty close to 14;)



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Re: Worn tyre, is it time to replace?

Postby pop » Thu Nov 20, 2014 7:42 am

You can improve the old tyres a bit , pump them up hard and ride around on some concrete pavement with some hard cornering and then spray some cheap arse wd40 on the tread area, that will soften the rubber and the cheap lube should evaporate away before riding. Or do some burnouts in the shed. :wink:




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