a question about tyre wear

[frankyknuckles]

Following ALOT of sideways action at Keevil earlier this week, I now have 2mm(ish) of tread left before the wear marks on all four of my CR500's. The total depth of the tread in the central grooves and most of the tread pattern on all tyres is 4mm. I have a track day at Bedford on Saturday, the weather is forecast to be dry and warm. There will be almost no sideways action at this trackday, do you think I have enough tread left to get me there (100+ miles) do the track day and get back again ?

 

I'm not that bothered if the tyres are then shot at the end of the day as I will have plenty of time to replace them before my next track day at Mallory.

 

I think I remember reading that CR500's are still good on track when almost no tread is left ???

 

www.R300.net

[oldbutnotslow]

4mm luxury ❗

Only worry when the cord starts to flop around!! 😬

 

Seriously 4mm should give you 2 days at least.

 

Grant

 

😬 183 BHP of black and stone chip excitement. 😬

here

[frankyknuckles]

Thanks 😬

Is a tyre technically illegal when the wear mark is flush with the top of the tread, or is it simply a guide to say that you are approaching the minimum legal tread depth

 

www.R300.net

[shn7]

The former I think. But bear in mind the wear bar will be flush with the rest of the tread from the point it becomes illegal to the time when the tyre pops because your worn through the carcass 😬.

 

Steve.

[Trevor Newman]

depends how old the tyres are as to where the wear band is

 

my cr322's wear bands are now at 3mm in preparation of next years new law 😬

 

bedford ❗ no sideways action you've got to be kidding 😬

 

Edited by - Trevor Newman on 7 Jul 2005 20:54:20

[Mike Bees]

I'm sure the wear markers have nothing to do with the law. There's usually more than the legal minimum amount of tread left at the wear markers.

 

Mike

[Graham Perry]

As Mike says the wear marker do not actually equate to the law. Most manufacturers have been setting these at 2mm to comply with the law in the USA, some I understand have been even deeper at 2.5mm. Always use a depth gauge for accuracy.

 

I had an argument with a police officer about wear marks many years ago as he said my tyres were illegal on an Fiesta tin top, I won the debate when I took my depth gauge out of my tool box and measured them to his reluctant satisfaction

 

Edited by - Graham Perry on 8 Jul 2005 08:26:33

[shn7]

Well I guess that's good news then. More wear to be had than I'd realised.

 

Steve.

[Sheds Moderator]

I was recently surprised when I used a depth gauge to measure my tintop tyres (just off the wear bars) - found 3mm tread remaining, smiled and put it back in the toolbox. This is on cheap tyres - I suspect they aren't too precise with the depth and put them on as an indicator only. Bear in mind also that some countries (Switzerland springs to mind) have 2mm limits.

 

What's this about a "new law" and 3mm?

[Shaun_E]

Don't know about a new law, but recent research has shown that once tread depth drops below 3mm then wet braking perfomance drops dramatically see here

Not sure where that leaves us A048R users - we only seem to get 4mm to start with 😬

 

Yellow SL #32

[Pooh_R]

couple of questions come to mind:

 

I had always thought the wear marks in the tread indicated the legal minimum. *confused*Please could someone clarify what the legal minimum is?

 

Trevor suggests there is some new law next year. What does this involve?

 

A Bear of little Brain!

[Mike Bees]

1.6mm at the moment IIRC. I'm sure it's in the tyre manufacturer's interests to make the wear markers pessimistic...

 

Mike