Safe Speed Forums

Front or back?

A lot of advice says put them at the back as understeer is easier to control than oversteer. However, front wheels do the majority of the work when braking so newer tires on the front should give better stopping power.

Thoughts?

If they are the same size, then front every time.

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Malcolm W.
The views expressed in this post are personal opinions and do not represent the views of Safespeed.

It depends which end you would rather not loose when cornering I think.

I would rather have more grip on the front than the back, especially for motorbikes.

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

There is also a wet grip issue. If your fronts are new, they will remove most water from the path of the rears which then can clear a little less and still grip.

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Malcolm W.
The views expressed in this post are personal opinions and do not represent the views of Safespeed.

All the 'expert' advice these days seems to be that new tyres should go on the back, but I prefer to have them on the front. I don't mind if the car faces the wrong way a bit at times, but I do not want the front end going straight on at a bend.

Best wishes all,
Dave.

Best tyres on the front, every time!

On which axle would you rather have a burst tyre?

rear every time, macho comments about oversteer aside
if the handling impact (understeer or brake efficiency) is that severe then you should probably be changing the fronts as well surely ?

as for which tyre you'd rather blow..... front please.

Much easier to deal with from what I understand.

On the OP, if the car has stability control does it matter?

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My first question has to be is your car FWD or RWD - or I guess 4WD ?

If front wheel drive - then take the best two tyres and keep them on the back placing the new one's on the front as they do most of the work.
If rear wheel drive - then take the best two tyres - usu the rears and put them on the front (usually swapped in pairs), and then have the new one's on the rear as they do the driving.
If 4wd - look at the split and apply accordingly to the great driving force.

I have always understood that the driving force is the greater issue. The scrub off the new tyres needs to be considered too I usually allow 250 miles but it may depend on where you go and what you do to be sure.
Unless you are going for remolds or 2nd hand - neither of which I would advise, unless you are really hard up.
I think blow outs are far more rare these days to be too significant - correct me chaps if I am wrong?

Make of tyre too gives different balances of performance. Height of tyre too might be considered esp if you live in a pot (black) hole spot !As in I would choose greater height tyres and have suspension and all steering components checked regularly.

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There is a school of thought that one should put the older tyres on the axle that does the MOST work, rather than the least (i.e. older tyres on the front of a front-wheel drive). In that way you "kill them off" sooner. Tyres loose grip as they age. They get hard as the rubber ages and they loose grip. Eventually, the sidewalls start cracking (especially if you live near the sea where there's lots of ozone and ultraviolet light). The rear tyres on a typical front wheel drive hatchback can last forever "in terms of tread wear" if the car doesn't do many miles and generally doesn't carry much weight in the back. I think there's probably a good argument for putting the new ones on the back to ensure that the ones that used to be on the rears end their days in a reasonable time whilst they still have some grip.

As for blowouts being rare, well I've never had one in getting on for 30 years of driving. I've had a few "sudden deflations" where the tyre has gone down in a few seconds but I don't think I've ever had a "blow-out" as such. When we were kids, we had one on an old Citroen DS (a back wheel) and my dad didn't notice- other than the change in road noise.

Not sure driving force is the biggest. Pretty certain it's braking force. There aren't many cars that can get from 0-100 in the same time as they can get from 100-0!

Is there actually much difference in performance between a brand new tyre and a partly worn one? Once you have enough tread to clear the worst case water, the extra rubber is only there to be worn away. Or am I, as is very likely, overlooking something

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

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Michelin seem to be saying that you should have the best tyres at the back in order to ensure maximum understeer which is ,apparently, safer than oversteer.

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

I don't know if this is true, but I'm under the impression brand new tyres are actually very bad for grip until they are "bed in". Is that correct, and if so, could that affect things?

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

That's the mold grease you are thinking about and it used to be worn off after a while - I usu allowed at least 50 miles .... but last yr I have been told 'you don't need to worry about it' but I think that is rubbish, I can definitely feel the slipperiness from them.
I have always placed the new tyres on the drive wheels.
I think the only 'blow-out' I have ever had was from a FWD car and I caught a piece of metal on the road and it destroyed the tyre, a very nearby layby solved my need to stop safely. Strictly it was a puncture but it did deflate exceptionally fast !

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Safe Speed for Intelligent Road Safety through proper research, experience & guidance.

The rule of thumb with motorbikes is 100 miles for 'scrubbing in' but this, so I have always been lead to believe, is because heavy acceleration or braking can make the tyre slip around the rim* thereby altering the balance and/or spoiling the integrity between rim and tyre.

If true, I would expect it to hold true with cars too although more so with the braking for obvious reasons...

My Polo 0-60mph = 13 seconds. My motorbike = 3 seconds


*Proof, if needed. My Kawasaki Z750 from 1975 had two bolts passing through the rim which held the tyre in place. Made changing tyres a right PITA I can tell you.

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

The back tyres on all of my front wheel drive cars have had hardly any wear on them, so a certain school of thought would say put the old one on the front to get the wear out of them before they degrade. But if your back tyres arn't old enough to perish, put the new one on the front. From what I can tell, on a FWD, the only thing the back wheels do is stop the back of the car dragging along the floor. I reckon I could drive my car if a back wheel fell off, that would be a whole lot trickier if a front wheel fell off.

With a good set of boots, the car will go where it's pointed and the back will come along one way or the other.

All the advice I've had was to fit new tyres on the rear .And with most cars being FWD -it possibly means that you change tyres before cracks start to appear in the tread .last car I bought -Astra ( ex mobility car so low mileage ,but three years old ) had to have all five changed - front two worn ,rear two tread cracking ( and only minimal wear) ,as was spare -all inside a year .

I know which axle I'd sooner have a tyre go down suddenly on - the front -had one go abroad on a 4x4 on the rear -and it was nasty .At least on front , you can use handbrake without affecting rear end .

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As I understand it, a brand spanking new tyre isn't that good. Partly, as Claire says, because of traces of mould release agent and the tyre soap they use to get it on to the rim. Also partly because the tread blocks still have the little "nodules" left from the moulding process which prevent uniform contact with the tarmac. The main reason, I think, is because they're not "scrubbed-in". Most cars run with a bit of camber (wheels leaning in or out at the top) and toe in or out. Camber, in particular, leaves the tyre running more on one edge than the other, so the contact patch isn't fully developed. After a few hundred miles they seem to develop optimum grip. After that, it drops off, although not always. In some racing formulas that dictate "road" tyres, the more well-heeled competitors will pay extra to have the tyres "buffed down" as close to the legal limit as they dare. This is where the tyre supplier simply grinds the tread off (or most of it), leaving as little tread depth as the regulations will allow. As you pitch the car into a bend, the first thing that happens, is that the tread blocks distort a bit, then the tyre carcass flexes, and then (and only then) does the car start to change direction. If you can eliminate tread block distortion, you can sharpen up the responses a minute amount. There are, however, other factors too. The number of "heat cycles" that a tyre goes through will reduce it's grip as the rubber hardens a bit every time it heats up and cools down. (OK, racing tyres get a lot hotter and start off softer so the effect is more pronounced). Finally, there's just "time" - during which the tyres get harder anyway as UV and ozone take their toll and the more volatile plasticisers leach out of the compound (which, I think, is why we don't notice an improvement in grip as a tyre gets to it's minimum tread depth - unless we do a huge mileages and drive very hard)!

Thank you Mole. You are a mine of information yet deliver it with a becoming modesty

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown