Newest tyres front or rear (RWD)?
Discussion
The rear, whichever end is driven. If one end of the car is going to aquaplane before you other, it's better if it generates snap under-steer so you hit the tree head on than snap over-steer so you hit it sideways.
It is true that braking in a straight line on standing water will be less efficient with them on the back, but personally I don't often do emergency stops in a straight line on standing water and if braking on a corner I'd rather the back end didn't lock up the first time I touch the pedal as all the weight shifts away from the poorer tyres, personally.
Of course, as someone said above, on many RWD cars you don't have any choice because the wheels are different sizes front to rear.
It is true that braking in a straight line on standing water will be less efficient with them on the back, but personally I don't often do emergency stops in a straight line on standing water and if braking on a corner I'd rather the back end didn't lock up the first time I touch the pedal as all the weight shifts away from the poorer tyres, personally.
Of course, as someone said above, on many RWD cars you don't have any choice because the wheels are different sizes front to rear.
Edited by kambites on Tuesday 22 September 09:01
Generally if one end is going aquaplane before the other it'll be the front regardless as that hits the puddle first. While I don't have hard data to prove it I would expect the speed/water depth combination necessary for say 4mm tread to grip while 3mm aquaplanes is quite specific, and not likely to be sustained for any significant distance in the real world.
GravelBen said:
Generally if one end is going aquaplane before the other it'll be the front regardless as that hits the puddle first. While I don't have hard data to prove it I would expect the speed/water depth combination necessary for say 4mm tread to grip while 3mm aquaplanes is quite specific, and not likely to be sustained for any significant distance in the real world.
kambites said:
GravelBen said:
Generally if one end is going aquaplane before the other it'll be the front regardless as that hits the puddle first. While I don't have hard data to prove it I would expect the speed/water depth combination necessary for say 4mm tread to grip while 3mm aquaplanes is quite specific, and not likely to be sustained for any significant distance in the real world.
zakelwe said:
Assuming a front wheel drive car ...
I'd put them on the front because it is the front that is being asked to do more jobs including steering and the majority of the braking load. That doesn't even take into account puddles or snow.
As stated before in the thread, this is the opposite view of all the tyre experts.I'd put them on the front because it is the front that is being asked to do more jobs including steering and the majority of the braking load. That doesn't even take into account puddles or snow.
Whilst the front grip and turns and passes water through etc. the rears don't and thus slide round. If there is big variation in grip (in the OP's case as rears are worn) then it can potentially be dangerous. i.e. you turn in at 50mph and think "great, lovely turn in, lots of grip" then the back which is also doing 50mph simply doesn't have the same level of grip and lets go. It's often too late to do anything about it as you've already commmitted at 50mph as that's how much speed the front told you you had!!! 50mph is just an example, could be any speed.
andye30m3 said:
I was always told to put the new tyres on the front based on the thinking of if you loose grip mid corner on the front tyres your into understeer and plow off the road where as is you lost grip on the rear tyres you have a chance of correcting the oversteer.
Again, the opposite view to tyre experts.You lose grip at front, you ease off and get grip back. You lose the rear and often there's little you can do, especially if the front it gripping well.
The first thing you have to realise (esp with the rear end going unexpectedly) is that most of us are NOT driving gods. There are some of course that do think they're driving gods, most of them you see their car wrapped round a tree
.Those 'tyre experts' you quote are aiming their advice squarely at the lowest common denominator though, and I would expect a much higher average understanding of vehicle dynamics on PH.
If you prefer dealing with understeer on the limit by all means put the best tyres on the back. If (like me) you prefer dealing with oversteer on the limit feel free to put them on the front instead. Assuming the same size tyres, if you don't like it you can always take 10 minutes to swap them round.
If you prefer dealing with understeer on the limit by all means put the best tyres on the back. If (like me) you prefer dealing with oversteer on the limit feel free to put them on the front instead. Assuming the same size tyres, if you don't like it you can always take 10 minutes to swap them round.
Noisy said:
Also everyone is assuming the new tyres will grip better than the old... depends on make compound and road conditions etc.
Thats a good point actually - the main point the 'new tyres religiously on the rear' brigade bring up is generally aquaplaning, but even that is down to tread design as well as depth.It would be quite interesting to see a comparison between worn tyres and brand new ones that aren't scrubbed in yet...
Dracoro said:
zakelwe said:
Assuming a front wheel drive car ...
I'd put them on the front because it is the front that is being asked to do more jobs including steering and the majority of the braking load. That doesn't even take into account puddles or snow.
As stated before in the thread, this is the opposite view of all the tyre experts.I'd put them on the front because it is the front that is being asked to do more jobs including steering and the majority of the braking load. That doesn't even take into account puddles or snow.
Whilst the front grip and turns and passes water through etc. the rears don't and thus slide round.
see what I mean? The tyres that do most of the work should have the best tyres on so allowing steering and braking to be done. If the back tyres are sliding then you have more options to control it if your good tyres are on the front, you have no options of control by using your good back tyres which are passive (assuming front wheel drive again).
I'm sure breaking distances go up massively as well in the rain or snow even if the car is less stable with the best tyres on the front.
For a front wheel drive vehicle the front tyres manage lateral grip, traction, steering and the majority of the braking. The rears do lateral grip and a small percentage of the braking. There is more to driving than stability.
Regards
Andy
GravelBen said:
Noisy said:
Also everyone is assuming the new tyres will grip better than the old... depends on make compound and road conditions etc.
Thats a good point actually - the main point the 'new tyres religiously on the rear' brigade bring up is generally aquaplaning, but even that is down to tread design as well as depth.They're all Michelin trained and they will absolutely only fit new tyres on the back. No exceptions. If you've got a staggered set-up they won't sell you fronts on their own unless the rears are close to brand new.
In my view this falls apart if you're replacing a grippy tyre with something Eco, in Michelin's case an Energy Saver. Following the mandate, Costco put these on the back on Mrs DL supermini and left decently treaded grippy Yokohama tyres on the front. I swapped them around as soon as we got the car home.
Funny you mention that, a tyre shop recently fitted relatively decent new rubber to the rear of the MX5, leaving kingstars (still with heaps of tread) on the front. I rotated them the next day, an MX5 should not power understeer on a wet road in 2nd gear.
For sure (because they're kingstars) low-speed oversteer is now very easy to provoke in the wet, but thats fine because I'm expecting it and can drive the car accordingly. Happy to accept its not for everyone though, you do have to be awake if you have a heavy foot. There is also a correspondingly significant improvement in braking performance with the kingstars swapped to the back.
For sure (because they're kingstars) low-speed oversteer is now very easy to provoke in the wet, but thats fine because I'm expecting it and can drive the car accordingly. Happy to accept its not for everyone though, you do have to be awake if you have a heavy foot. There is also a correspondingly significant improvement in braking performance with the kingstars swapped to the back.
Edited by GravelBen on Tuesday 22 September 14:05
Newer on the front, especially if they're directional - they'll clear more standing water so the rear's have less to do (IYSWIM).
IMHO there'll be little difference in dry grip and braking between a part-worn and a near-new (if the rears are almost dead, then that's different, just change all 4).
IMHO the experts are wrong...for someone who actually knows how to drive a rwd car.
IMHO there'll be little difference in dry grip and braking between a part-worn and a near-new (if the rears are almost dead, then that's different, just change all 4).
IMHO the experts are wrong...for someone who actually knows how to drive a rwd car.
GravelBen said:
Those 'tyre experts' you quote are aiming their advice squarely at the lowest common denominator
havoc said:
IMHO the experts are wrong...for someone who actually knows how to drive a rwd car.
Silly old experts - fancy them making up all that industry nonsense just to confuse the public.GravelBen said:
For sure (because they're kingstars) oversteer is now very easy to provoke in the wet, but thats fine because I'm expecting it and can drive the car accordingly. Happy to accept its not for everyone though, you do have to be awake if you have a heavy foot.
Hmmm...perhaps you're a driving God, but for more ordinary drivers it's not often that the space exists on public roads to correct oversteer, epecially if it occurs halfway around a bend on a single carriageway road with traffic coming the other way.havoc said:
Newer on the front, especially if they're directional - they'll clear more standing water so the rear's have less to do (IYSWIM).
IMHO there'll be little difference in dry grip and braking between a part-worn and a near-new (if the rears are almost dead, then that's different, just change all 4).
IMHO the experts are wrong...for someone who actually knows how to drive a rwd car.
I agree and in a previous post as for costco only fitting tyres where they think they should be - I'll take advice sure but I am the customer so if they won't do what I ask I'd shop elsewhereIMHO there'll be little difference in dry grip and braking between a part-worn and a near-new (if the rears are almost dead, then that's different, just change all 4).
IMHO the experts are wrong...for someone who actually knows how to drive a rwd car.
When not faced with staggered widths I normally manage my tyres by rotation so that they are all worn out at the same time and I buy a set of four
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