Michelin Pilot Sport Two (PS2) 225/40/18 92Y Extra Load : Review

[RedRobin]

Thanks - yes, I knew that your kit had the transmitters in the new valves, which get mounted on the inside of the rim - but when something 'transmits' - then there also needs to be a 'receiver' too.

So on cars with factory fitted 'direct acting TPMS' (direct acting means it measures the actual pressure, rather than uses wheel rotational differences from the wheel speed sensors) such as Renaults, Vauxhalls and Audis - they use those same valve transmitters as you have in your TyreSure kit, but they also have four remote 'antenna' in each wheel arch.  So basically, not only are the actual tyre valves 'coded' to the TPMS 'head unit' (for want of a better phrase), but also the wheels are 'positioned' on the vehicle too.

....No antennae in the wheel arches but you do have to 'connect' the wheel positions individually to the display unit as part of the setup. You then revise it as you revise tyre positions etc.

[We ought to be discussing this in the review thread]

[stealthwolf]

Can I kindly suggest you actually read the full text on the side of the tyre to which that comment relates to!  I'll give you a clue - it does NOT apply to the UK or EU.

Honestly, TT it was something I noticed but didn't pay much attention to. I've never needed to inflate the tyres above 40psi! Will have a closer look tomorrow!

There is absolutely NO confusion. 

I'm not the one confused TT. I've only ever checked my tyres when cold - as we've discussed in person - using a PCL type guage in the mornings when the atmosphere is cooler. I'm a good boy! 

I inferred that the previous poster may have been confused/misinformed about the '50psi' warning and may have interpreted it as not to exceed 50psi at all (so s/he may have thought that the limit would have been exceeded when the tyres were hot rather than exceeding the limit when tyres were cold, if that makes any sense!).

And just to clarify, a tyre can heat up in as little as half a mile.

Which is something you reminded me at the JKM meet and hence have never bothered checking tyre pressures unless when cold.

Tyres are categorically and specifically designed to cope with increases in pressue as the tyre heats up - and they have absoultely MASSIVE threasholds for 'overinflation'.

This is something I'm well aware of but wasn't sure whether the previous poster was!

I've regularly inflated road-legal tyres to over 140psi - and have NEVER had a tyre fail due to over pressure!

For educational purposes, why would you do this?

[tony_danza]

Finally I think running 44PSI is dangerous and I'm surprised you're recommending it. On a spirited drive I can see my pressures come up by around 4-6PSI depending on the weather, by that same reckoning, you'd be near or at the maximum limit of 50PSI and serious risk of tyre failure.

What an utter load of bollox!  I supposed you think I should get locked up for attempted manslaughter by running 85psi in my bicycle tyres!

HTF can 44psi be dangerous?  What about the 61psi in the space saver - do we have to have a 'Hazardous Substance' warning sticker on our tailgates!

The mind boggles how you can even post such statements!

I don't know, what does it say on the sidewall of your bicycle or the spacesaver regarding the maximimum permissable inflation?
  
I know for a FACT it says you DO NOT EXCEED 50PSI on the sidewall of a 225/40/18 Michelin PS2, and that is what we're talking about here after all... not bicycles, not egos, just PS2s.

You admit that tyre pressures can go up by a marked amount further up in this thread, yes? You therefore MUST accept that your tyres, at 44PSI when hot, will be reaching upwards of the tyre manufacturers MAXIMUM limit??

Am I wrong in that statement?

If you're happy to explrore the "thresholds" of the tyre, then fine - crack on.

If you're telling me I'm an idiot for running 2PSI under recommended when I've accounted for my tyres getting hotter than the fuel flaps "middle of the road" settings... why am I not granted the same threshold?

In my opinion though, you are handing out dangerous advice to people clouded by an arrogance of 'having to be right', even when you probably know better.

Immeadiately dropping to base level of insult and aggression is the act of a child, you should be ashamed of yourself.

[JPC]

  this smiley will be getting tired with how many uses it's had of late

[stealthwolf]

I know for a FACT it says you DO NOT EXCEED 50PSI on the sidewall of a 225/40/18 Michelin PS2, and that is what we're talking about here after all... not bicycles, not egos, just PS2s.

You admit that tyre pressures can go up by a marked amount further up in this thread, yes? You therefore MUST accept that your tyres, at 44PSI when hot, will be reaching upwards of the tyre manufacturers MAXIMUM limit??

See, I saw something like that and interpreted it as not exceeding 50psi when the tyres are cold, as that's when you're supposed to check (and adjust) the pressures.

Given that tyres vary in their pressure as you drive, combined with weather conditions, you cannot guarantee what pressures you might reach when say driving on a long journey on a hot day with a full load. If you set the tyre pressures at, say 42psi, you may exceed 50psi, in which case you risk tyre failure. In this case, it would be negligent for the manufacturers if they did not put a lower limit eg 40psi, so that 50psi is never reached.

It may be the case that the PS2s bugger up after 60psi, so to keep on the safe side, Michelin may have used 50psi as a safety limit as exceeding this would mean the possibility of exceeding 60psi when driving would be prevented.

After all, unless you have a TPMS like RR, you're not gonna stop on the motorway at intervals just to check tyre pressures.  

[tony_danza]

Yes, but it is exponential. The more air in the tyre, the more there is to expand.

My average increase at 34 may be 5PSI hot. At 44PSI it could be 10PSI - I have used my average as a conservative estimate.

The point is he's allowing himself all that threshold, yet a touch below is making him spit bile.

A tyre at that pressure on a car of our weight is a greasy mess and makes driving it like trying to keep a cat in a bath tub.

[RedRobin]

Given that tyres vary in their pressure as you drive, combined with weather conditions, you cannot guarantee what pressures you might reach when say driving on a long journey on a hot day with a full load. If you set the tyre pressures at, say 42psi, you may exceed 50psi, in which case you risk tyre failure. In this case, it would be negligent for the manufacturers if they did not put a lower limit eg 40psi, so that 50psi is never reached.

It may be the case that the PS2s bugger up after 60psi, so to keep on the safe side, Michelin may have used 50psi as a safety limit as exceeding this would mean the possibility of exceeding 60psi when driving would be prevented.

After all, unless you have a TPMS like RR, you're not gonna stop on the motorway at intervals just to check tyre pressures.  

....So far - A varied journey on Tuesday of 512 miles and 100 today, both in all sorts of conditions and speeds - I have found that the pressures have only fluctuated about 3 psi. Whereas the tyre temperatures have fluctuated as much as 15ºC and the fronts are mostly hotter than the rears (as you would expect).

^ This is according to my TyreSure TPMS.

[Teutonic_Tamer]

Thanks - yes, I knew that your kit had the transmitters in the new valves, which get mounted on the inside of the rim - but when something 'transmits' - then there also needs to be a 'receiver' too.

So on cars with factory fitted 'direct acting TPMS' (direct acting means it measures the actual pressure, rather than uses wheel rotational differences from the wheel speed sensors) such as Renaults, Vauxhalls and Audis - they use those same valve transmitters as you have in your TyreSure kit, but they also have four remote 'antenna' in each wheel arch.  So basically, not only are the actual tyre valves 'coded' to the TPMS 'head unit' (for want of a better phrase), but also the wheels are 'positioned' on the vehicle too.

....No antennae in the wheel arches but you do have to 'connect' the wheel positions individually to the display unit as part of the setup. You then revise it as you revise tyre positions etc.

[We ought to be discussing this in the review thread]

OK, do you wanna ask the mods to copy the relevent posts over! 

[Teutonic_Tamer]

Can I kindly suggest you actually read the full text on the side of the tyre to which that comment relates to!  I'll give you a clue - it does NOT apply to the UK or EU.

Honestly, TT it was something I noticed but didn't pay much attention to. I've never needed to inflate the tyres above 40psi! Will have a closer look tomorrow!

 

There is absolutely NO confusion. 

I'm not the one confused TT. I've only ever checked my tyres when cold - as we've discussed in person - using a PCL type guage in the mornings when the atmosphere is cooler. I'm a good boy! 

Sorry mate, I didn't mean to imply you personally were confused - more of a 'general' comment. 

I inferred that the previous poster may have been confused/misinformed about the '50psi' warning and may have interpreted it as not to exceed 50psi at all (so s/he may have thought that the limit would have been exceeded when the tyres were hot rather than exceeding the limit when tyres were cold, if that makes any sense!).

Exactly - and he still hasn't got it!

And just to clarify, a tyre can heat up in as little as half a mile.

Which is something you reminded me at the JKM meet and hence have never bothered checking tyre pressures unless when cold.

 

Tyres are categorically and specifically designed to cope with increases in pressue as the tyre heats up - and they have absoultely MASSIVE threasholds for 'overinflation'.

This is something I'm well aware of but wasn't sure whether the previous poster was!

Again, not at you mate, but arrogance is bliss elsewhere, if you get my drift! 

I've regularly inflated road-legal tyres to over 140psi - and have NEVER had a tyre fail due to over pressure!

For educational purposes, why would you do this?

Think BIG, very big. 

[stealthwolf]

You mean like lorries and tractors? But surely the tyres are designed to withstand such pressure on such vehicles?

[Teutonic_Tamer]

Finally I think running 44PSI is dangerous and I'm surprised you're recommending it. On a spirited drive I can see my pressures come up by around 4-6PSI depending on the weather, by that same reckoning, you'd be near or at the maximum limit of 50PSI and serious risk of tyre failure.

What an utter load of bollox!  I supposed you think I should get locked up for attempted manslaughter by running 85psi in my bicycle tyres!

HTF can 44psi be dangerous?  What about the 61psi in the space saver - do we have to have a 'Hazardous Substance' warning sticker on our tailgates!

The mind boggles how you can even post such statements!

I don't know, what does it say on the sidewall of your bicycle or the spacesaver regarding the maximimum permissable inflation?

 
Well then maybe you ought to check before making such sweeping statements as you did earlier in the thread.  Yes, sure, a bicycle tyre is a bit of an extreme and slighty irelevant example - but a spacesaver is categorically NOT irellevent!

I know for a FACT it says you DO NOT EXCEED 50PSI on the sidewall of a 225/40/18 Michelin PS2,

The you have just completely shot yourself - because that IS NOT RELEVENT TO UK OR EU MARKETS.  It form no legal requirements, nor no 'advisory' requirements either.  You are massively out of your depth in this particular issue!

and that is what we're talking about here after all... not bicycles, not egos, just PS2s.

You seem to be the one with the massive 'ego' problem.  Because you categorically DID NOT state we were just dealing with PS2s.  Talk about moving the goal posts!

You admit that tyre pressures can go up by a marked amount further up in this thread, yes? You therefore MUST accept that your tyres, at 44PSI when hot, will be reaching upwards of the tyre manufacturers MAXIMUM limit??

Am I wrong in that statement?

Of course you are wrong!  You are massively wrong - on two counts.

First, tyre pressures should ONLY be checked when the tyre is COLD.  Pressures are NOT the limiting factor.  It is the upper limits of tyre TEMPERATURES which are the limitiing factors - why the heck do you think that they don't bother with measuring the pressures - but DO measure temperatures - during motorsports meetings?

Secondy, simple laws of physics dictate that pressures will rise when a tyre heats up.  This is PERFECTLY NORMAL - and provding the temperature doesn't rise too much, is perfectly within design parameters.  Or do you not think that tyre manufacturers didn't realise that tyres get warm during use!

If you're happy to explrore the "thresholds" of the tyre, then fine - crack on.

So what do you think you are doing?  Pot, kettle and black come to mind. 

At least I have a professionally educated understanding of what I am doing!

If you're telling me I'm an idiot for running 2PSI under recommended when I've accounted for my tyres getting hotter than the fuel flaps "middle of the road" settings... why am I not granted the same threshold?

I never said you personally were an 'idiot'.  What I did say was that it is recommended never to go below the recommended settings.  And as I've also pointed out - they are just 'recommendations'.  Furthermore, in many other threads, I've explained the 'science' behind how tyre pressures can be 'adjusted' or tweaked.

And for the record, I don't have a problem with you personally running lower pressures - afterall, its your car, and your own 'butt dyno' should be giving you first hand feed back of what the car is doing.  But I do have a problem when peeps make a sweeping statement to others to lower their pressures - especially when there is a shed load of info in the public domain about how dangerous under-inflated tyres are.

In my opinion though, you are handing out dangerous advice to people clouded by an arrogance of 'having to be right', even when you probably know better.

But my advice is NOT dangerous.  My advice is supported by the Tyre Industry Council, along with all the major tyre manufacturers, and most modern car manufacturers - who ALL now state that cars should be run ALL the time on the 'full load' pressures (unless there is some exceptional over-riding reason not to).  Or do you also think that the TIC and all the tyre manufactures, and the vehicle manufacturers are wrong - and are giving out dangerous advice?

Immeadiately dropping to base level of insult and aggression is the act of a child, you should be ashamed of yourself.

Huh - black cooking items again.  Or is it just you who somehow has an absolute right to make unqualified dangerous statements - whilst being exempt from challenges?

[Teutonic_Tamer]

this smiley will be getting tired with how many uses it's had of late

Best you get a massive tub of Ben and Jerrys - Phish Food for me, and get some extra spoons too!

[Teutonic_Tamer]

I know for a FACT it says you DO NOT EXCEED 50PSI on the sidewall of a 225/40/18 Michelin PS2, and that is what we're talking about here after all... not bicycles, not egos, just PS2s.

You admit that tyre pressures can go up by a marked amount further up in this thread, yes? You therefore MUST accept that your tyres, at 44PSI when hot, will be reaching upwards of the tyre manufacturers MAXIMUM limit??

See, I saw something like that and interpreted it as not exceeding 50psi when the tyres are cold, as that's when you're supposed to check (and adjust) the pressures.

You are correct with your wisdom on the cold tyre pressures.  But as the old saying goes "a little knowledge can be a bad thing" (or sommat along those lines) - the devil is in the detail.  Those maximum pressures are NOT for the UK or Europe (nor are they for Asia, Australasia, Africa, or South America) - they are specific to half of one continent and have bu&&er all to do with us.

Given that tyres vary in their pressure as you drive, combined with weather conditions, you cannot guarantee what pressures you might reach when say driving on a long journey on a hot day with a full load. If you set the tyre pressures at, say 42psi, you may exceed 50psi, in which case you risk tyre failure. In this case, it would be negligent for the manufacturers if they did not put a lower limit eg 40psi, so that 50psi is never reached.

You are making great sence with your theories and deducements.

It may be the case that the PS2s bugger up after 60psi, so to keep on the safe side, Michelin may have used 50psi as a safety limit as exceeding this would mean the possibility of exceeding 60psi when driving would be prevented.

But this is where you come to a grinding halt in your progress.

Tyre pressures are NOT the limiting safety factor.  It is ONLY tyre temperature.

Secondly, Michelin, like all other tyres supplied to US markets - MUST, in order to comply with their US Department for Transportation (DOT) - state things like maximum pressures.  Just like in microwave instruction manuals, they have to categorically state that the microwave must NOT be used to dry out live pets (little doggies who got wet in a rain shower).  The Yanks have a very 'agressive' sue you strategy - which is why virtually everything from tyres to test tubes must have incredibly specific, and anal instructions of what you can and can not do.

After all, unless you have a TPMS like RR, you're not gonna stop on the motorway at intervals just to check tyre pressures.  

Exactly.  And furthermore, it is exactly for the reason of tyres heating up, and therefore increasing in pressure - that manufacturer fitted direct acting TMPS are calibrated and set up NOT to warn you of increases in tyre pressures.

[Teutonic_Tamer]

Yes, but it is exponential. The more air in the tyre, the more there is to expand.

More BS.  Air is compressible.  The tyre contains a fixed volume - so there is NO expansion.  Once a tyre is inflated, it assumes a nominal volume, and that volume will remain static irrespective of weather it has 30 psi or 130 psi.

The point is he's allowing himself all that threshold, yet a touch below is making him spit bile.

I'm making a point of 'my threshold' simply because that is an 'industry standard' - and not some personal whim which you seem to think.

A tyre at that pressure on a car of our weight is a greasy mess and makes driving it like trying to keep a cat in a bath tub.

What an utter load of nonsence.  Just how much force do you think goes into your front tyres when when you press the middle pedal v.hard at say 70mph - especially with your added Alcons?

[Teutonic_Tamer]

Given that tyres vary in their pressure as you drive, combined with weather conditions, you cannot guarantee what pressures you might reach when say driving on a long journey on a hot day with a full load. If you set the tyre pressures at, say 42psi, you may exceed 50psi, in which case you risk tyre failure. In this case, it would be negligent for the manufacturers if they did not put a lower limit eg 40psi, so that 50psi is never reached.

It may be the case that the PS2s bugger up after 60psi, so to keep on the safe side, Michelin may have used 50psi as a safety limit as exceeding this would mean the possibility of exceeding 60psi when driving would be prevented.

After all, unless you have a TPMS like RR, you're not gonna stop on the motorway at intervals just to check tyre pressures.  

....So far - A varied journey on Tuesday of 512 miles and 100 today, both in all sorts of conditions and speeds - I have found that the pressures have only fluctuated about 3 psi. Whereas the tyre temperatures have fluctuated as much as 15ºC and the fronts are mostly hotter than the rears (as you would expect).

^ This is according to my TyreSure TPMS.

And have you noticed any difference, mainly in temperatures, between 'normal' driving - and then compared it with a few repeated heavy braking occurances (letting those big APs do some serious work ) ?