How much tread is typically on a brand new tyre?

[EazyDuz]

Just morbid curiosity really. It would be a good way to gauge how long a tyre would last if measured every 1000 miles.
The legal limit for a bike is 1mm across the entire width of the tyre correct? And 1.6 for a car across central 3/4s?
1mm seems like nothing as well, how could that be at all safe in the wet?
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To shreds you say? Tss tss tss

[stinkwheel]

You have to be going pretty damned fast to aquaplane a motorcycle tyre due to the small contact patch and round profile. Far less likely to happen that on a car. The tread is only there to clear water, it's the compound that grips.

If you think 1mm is bad, you need "visible tread" on vintage mopeds.

I don't think your idea will work though, they seem to wear down faster towards the end of their life- possibly due to heating up more? Be interesting to test though. Do report back with what you find.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Evil Hans]

[Pete.]

All sorts of things happen as a tyre ages/wears. Tyre tread depth and ability to clear water is only one aspect of safety. Take two tyres of the same type on new the other worn, one will have a nice firm feel and stiff carcass, the other will be floppy as a wet rag.

Used to drive my missus mad when I'd buy new tyres to take to the runway if mine were even half-worn. I just didn't fancy running 200mph+ with the tyres at 50psi on worn carcasses. Apart from that the reduction in rolling resistance was very apparent on a new tyre.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[JackButler]

If you need to rely on legislation to tell you when it's come time for new tyres . . . . Then you really do need that job pays slightly above minimum wage & then cost of new tyres isn't as much of a problem.
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I clean my guns with the tears of the snivelling, left wing scum.

[mentalboy]

[EazyDuz]

[The Shaggy D.A.]

[Freddyfruitba...]

FWIW, my current tyres (Michelin PR4) had 5mm on the front and 6.5mm on the back, when new.

[blurredman]

I do find it interesting that the more the tyre wears, the quicker it wears. I though perhaps that less flex in the tread would occur.


That said, I myself have just experienced a tyre that 'will need preparation for replacement soon' (like buying the tyre), has after only 500 miles suddenly become 'that tyre is borderline illegal'.
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CBT: 12/06/10, Theory: 22/09/10, Module 1: 09/11/10, Module 2: 19/01/11
Past: 1991 Honda CG125BR-J, 1992 (1980) Honda XL125S, 1996 Kawasaki GPZ500S.
Current: 1973 MZ ES250/2 - 17k. , 1979 Suzuki TS185ER - 9k, 1981 Honda CX500B - 91k, 1987 MZ ETZ250 (295cc) - 38k, 1989 MZ ETZ251 - 49k