what the hell is going on with our roads.

smaller wheels, or if you have the likes of VW's DCC(real time adaptive suspension) that probably help reduce pot-hole shock on the wheel/tyre as the motion of the body is more damped.

e: or .. big wheel trend was set by the high end cars, but the prols didn't realise they had adaptives and air suspension

Big wheels are also supposed to have high profile tyres, but they glossed over that because they prioritise looks over functionality
 
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smaller wheels, or if you have the likes of VW's DCC(real time adaptive suspension) that probably help reduce pot-hole shock on the wheel/tyre as the motion of the body is more damped.

e: or .. big wheel trend was set by the high end cars, but the prols didn't realise they had adaptives and air suspension

Please explain what you think you are suggesting with 'real time adaptive' its certainly not road reading technology.
Big wheels are also supposed to have high profile tyres, but they glossed over that because they prioritise looks over functionality

No they aren't, what ladybird book did you read that in?
 
Please explain what you think you are suggesting with 'real time adaptive' its certainly not road reading technology.
recent discussion in the bmw thread about whether adaptive suspension adapts real time, so I qualified it,
if it is tuned so that it is softer by default (and usually tightens when you want to manouver) then hitting a pot-hole should give less impact on consequent chassis movement,
yes, it can't react instantly, to soften impact further, as wheel falls into pothole, - maybe magnaride or perhaps mercedes camera system that sees pot-hole are better.

need to ask the guy in bmw thread who held out for 5 series w/adaptives how they fare on pot-holes
 
My Focus has pothole detection - As soon as you hit one it makes a loud crashing sound.

I have binned my 18" wheels and rubber band tyres and now have 205 16" alloys with pressure up a few pounds.
 
Please explain what you think you are suggesting with 'real time adaptive' its certainly not road reading technology.


No they aren't, what ladybird book did you read that in?

Yes they are otherwise the ride is horrible. As it is on many cars using large wheels...

Low profile only works on small and light wheels and only then on nice tarmac.
 
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Ride was pretty good on my Volvo with 22s, even over lumps and bumps, that wasn't the issue for me, tyre longevity was the main issue, after a split, a nick and a puncture decide it wasn't the right tyre for where/how :D we drive.
 
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Not trying to absolve councils of their obligation to fix potholes but I have two points to make.

1. Totally agree with everyone about rim size and tyre side wall. I honestly don't understand the desire for a tiny side wall and a huge rim. Tarmac race cars still have a fair bit of sidewall so it certainly isn't going to make you any faster, so why? Morons who opt for huge rims and tiny sidewalls (especially on heavy cars) for aesthetic reasons deserve to have their rims buckled. I have a 20yr old hot hatch, and even I've downsized on rims for the sake of practicality. The car came from factory with 195/45/17s, I've downsized to 16" rims and use 205/50/16 tyres, I even tried 205/55/16 but they rubbed on the suspension. As a bonus the tyres with more sidewall are usually cheaper, only £90 per corner for top tier rubber for mine. I'm usually good at avoiding potholes but have still hit a fair few over the years, never once damaged a tyre or a rim and I drive all over the country, maybe helpful that the vehicle mass is only 1400kg though haha.

2. Road damage is proportional to the fourth power of axle load, i.e. if you double the load on an axle, it causes 16x more damage to the road. Anyone who knows their physics/engineering will know it's quite rare to find a relationship with an exponent as high as four (the only other example I can think of is the Stefan-Boltzmann equation for luminosity of a black body). This means that HGVs and buses cause 90% or more of the wear and tear to the road surface (notice how there's usually damage or subsidence at bus stops). I don't know whether HGVs are being under-taxed or the taxes are being badly utilised but something needs to change here.
 
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maybe helpful that the vehicle mass is only 1400kg though haha.
Probably something in that, the profile is smaller on my Abarth Punto running 215/40/18 and not had an issue but its under 1100kgs versus the Volvos 2150kgs though I did go through a spate of PS4 tyre damage but that was after years of running other brands that had no issue on same wheel, so rather than downsize in this case I switched to continentals and over time goodyear super sport and had no tyre failures since, so just put that down to PS4 being unsafe in that size and pressure, I did contact Michelin about it, zero ***** given. Michelins softass sidewalls no doubt the culprit.
 
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Ride quality is excellent in our XC90 on 22's with air suspension.

The air suspension is taking all the punishment and wear. Most cars just have regular springs and shocks. The ride quality on the big Audi's without the air suspension is awful.
 
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Hit a pothole that was on a left hand sweeping bend on a country road. Blew the tyre pretty much instantly. (205/45/R18) Thankfully I was going at a reasonable speed. Had to limp the car about a half mile on the flat to find safe space to put the space saver spare on.
 
2. Road damage is proportional to the fourth power of axle load, i.e. if you double the load on an axle, it causes 16x more damage to the road. Anyone who knows their physics/engineering will know it's quite rare to find a relationship with an exponent as high as four (the only other example I can think of is the Stefan-Boltzmann equation for luminosity of a black body). This means that HGVs and buses cause 90% or more of the wear and tear to the road surface (notice how there's usually damage or subsidence at bus stops). I don't know whether HGVs are being under-taxed or the taxes are being badly utilised but something needs to change here.

Around here we have more and more HGVs and other larger vehicles squeezing down smaller and smaller roads - it is catastrophic for the road surfaces especially those they've done a half-arsed job on.
 
Yeah there are 4 sections on my way to work that are a nightmare. One junction looks like it’s been bombed. Outside pride park stadium is really bad and been like that for months. I had thought that as the sun zero weather was done for the year they would be out sorting them out and they don’t look like they are interested in even patching them up. I have just bought a new car and regretting the sport suspension at the moment.
 
Where I am they are in a state of decay, lots of the most recent surface tarmac has been worn away revealing older surfaces, loads of potholes too and an abnormal amount of sink holes seeming forming also, I guess it's a sign our local council is short of money, as it never used to be this bad, not on so many roads and not since before Covid at least
 
and an abnormal amount of sink holes seeming forming also

One of the ones I find weird is the amount of identical size/shape sink holes which seem to be forming, they are almost all in positions which would be taking the max beating from vehicles, especially heavy vehicles though i.e. the right hand side of the lane on a sharp right hand turn.
 
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