Safe Speed Forums

A simple analogy for you.

How long does a frying pan handle have to be to stop you burning your hand?
It depends on your pain threshold, how hot the hotplate is, the diameter of the hot plate in relation to the conductivity of the metal, and whether you need to move the frying pan in the first place.

The cross sectional area, and the design of the tread determines the amount of water it can shift. The amount of water, and the vehicle speed determines the amount of water it NEEDS to shift.

If you are a 70 year old Rover driver in a flatcap, 1.6 mm may well be adequate. If you only get your car out in the dry, it should be more than sufficient.
If you are a 18 year old boy racer, with a budget which limits you to cheap Korean rubber, then I wouldn't let you out on the road with just 1.6 mm.
The legal minimum is just that - the bootom end of the scale.
Common sense in relation to driving style and conditions should be the deciding factor - and the manufacturers in my experience have only one criteria - their shareholders!!

I hoped to change my tyres in France while on holiday (because they are cheaper), but the depth on one was of concern enough to change the week before, because I knew I would be travelling 300 miles on motorway, with a deadline departure time for the ferry, possibly in the wet, and with all the family in the car.
I also had the used but low mileage tyre rotated with the brand new spare, in anticipation of having at some point to put the spare on with already worn tyres.
(Cannot remember who suggested that, but it wasn't on a safety camera website!!)
As it happened, the closure of the Motorway southbound between Lancaster and Preston, (with NO SIGNAGE OR EXPLANATION) and roadworks with 50 limits (but no workers) further south, ate into our spare time allowed, and between Oxford and Portsmouth, I was forced to make maximum use of the limits allowed to ensure we arrived on time.
At the end, I had only 15 minutes to our check in time, and because it was dry, my tyres would not have been an issue or concern - but better safe than sorry!!

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

stopping chart

As for the height of the indicators this page says


so they're obviously set higher than 1.6mm.

Glad about that since I change tyres when the wear bar starts showing. I treat wet roads with a great deal of caution anyway, probably more than absolutely necessary but I'm inclined to think that my car is less than happy on wet surfaces anyway.

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Make everything as simple as possible, but not simpler - Einstein

A while back a friend had a leased company car, and when he went in to get the tyres changed the tyre shop said that there was too much tread left and that lease company didn't change them at that level (there was 2mm I think). He called the lease company and the person on the phone said that they only change them when the depth is below 1.6mm. He asked them whether they seriously expected him to drive around with illegal tyres and the reply was yes!

He eventually got them changed, I think he told them that he would get some friends to hold the front of the car down while he burned the rest of rubber away (outside Kwik Fit).

Gareth

Slightly different I know but I change my bike tyres when I feel they are no longer producing the handling I expect. I recently threw away a front tyre with 3mm of tread across the middle two thirds of the tyre and all the way around as it had a really bad wear pattern on the off side cornering surface, I normally dispatch a rear whilst it still has a couple of mil as the middle is flat and it doesn't corner.

1.6 (1)mm may well be the legal minimum but that doesn't mean that it is still optimum for handling, after all on a moped there just has to be visible tread, and that isn't a lot at all.

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Former Military Police Officer and accident investigator

hi guys
the research for this was carried out by mira, motor industry research centre.this was done a while ago, though as i said the industry are in support.roadsafe concerns its self on fleet safety and the fleets are quite wary. lease, rental etc costs or is it necessary.im not sure. regular checking of tyres are important.the energy savings trust state that correct pressures will save fuel and are safe.......because of the work i do on the roadsafe publication i will keep you guys informed of all sorts of campaigns as i hear them if intresting for discussion . hope thats ok
goldy

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Audere Est Facere.....To Dare Is To Do

3mm is a crap idea. Some people buy cheap crappy budget tyres which struggle to grip in any conditions, no matter what the tread level is. For someone like myself who gets through way more expensive, grippy and therefore safer Goodyear Eagle F1s (the best all round tyre imo) in 6 to 8 months, the motivation for buying the better tyres would be reduced if I had to replace them every 4 to 6 months!

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