{"id":8112,"date":"2017-12-05T07:34:35","date_gmt":"2017-12-04T21:34:35","guid":{"rendered":"https:\/\/www.privatefleet.com.au\/blog\/?p=8112"},"modified":"2020-06-20T00:34:10","modified_gmt":"2020-06-19T14:34:10","slug":"goldilocks-goodyear-and-the-three-tyre-pressure-bears","status":"publish","type":"post","link":"https:\/\/www.privatefleet.com.au\/blog\/safety-2\/goldilocks-goodyear-and-the-three-tyre-pressure-bears\/","title":{"rendered":"Goldilocks Goodyear* And The Three Tyre Pressure Bears"},"content":{"rendered":"

 <\/p>\n

\"\"Getting the tyre pressure right is a bit of a Goldilocks process \u2013 it can\u2019t be too hard or too soft, but has to be just right.\u00a0 If you don\u2019t get it right, it could result in an accident that leaves you looking like you have indeed had an encounter with three grouchy, hungry grizzly bears. Or it could turn your vehicle into a beast with one heck of an appetite for fuel. (On a complete sidetrack, wouldn\u2019t Ursus or the word for Bear in some other language make a great name for a 4×4?)<\/p>\n

The most common scenario is that you end up with Mama Bear\u2019s tyres: too soft.\u00a0 This is because valves aren\u2019t perfect and slow leaks happen over time, what with little air molecules being sneaky.\u00a0 Ideally, we ought to check our tyre pressure monthly but not many of us actually do this (and that\u2019s me at the front of the queue for the confessional!).<\/p>\n

The problem with too-soft Mama Bear tyres is that they bulge out.\u00a0 This leads to two problems.\u00a0 Firstly, because the walls of the tyre weren\u2019t designed to balloon out like that, you\u2019re increasing the chance of the tyre going boom on you.\u00a0 Yes \u2013 underinflation and being too soft is what increases the chance of getting a blowout, not being too hard.<\/p>\n

The second problem of having too-soft Mama Bear tyres that bulge out is because this increases the area of tyre contacting the road.\u00a0 A moment\u2019s thought will tell you that this has to be better for grip, right?\u00a0 Well, yes.\u00a0 It does increase the amount of grip between the tyre and the road surface, and that\u2019s just the problem.\u00a0 This means increased friction, and this means that your car has to work harder to get up to the speed you want to.\u00a0 Remember what it was like when you were a kid and your bike tyre started getting a leak so you had to pedal that much harder when the tyre was flat?\u00a0 Well, the same thing happens when your car tyres are flat (or your trailer tyres for that matter).\u00a0 What this adds up to is terrible, terrible fuel economy.\u00a0 If you\u2019ve wondered why you don\u2019t get the same fuel economy as the stats in the car ads say you should, this is one of the reasons why (the other reasons are because the vehicles are tested minus any load at all and in the lab where there\u2019s no crosswinds or headwinds).<\/p>\n

OK, so having the tyres too soft is a bad thing.\u00a0 However, is there such a thing as being too hard?<\/p>\n

As Goldilocks would tell us, yes, tyres can be too hard.\u00a0 Papa Bear tyres might not increase your chance of a blowout the same way that Mama Bear tyres do, in spite of what the cartoons tell us. Papa Bear tyres are dangerous in another way.\u00a0 Because they make the bottom of the tyre narrower and more convex, there\u2019s less of the tyre touching the road.\u00a0 This means less friction.<\/p>\n

Less friction, of course, means less grip around corners and greatly increased braking time.\u00a0 If it\u2019s wet, then proportionally less water can be channelled out of the way, so the friction decreases even further.\u00a0 Let\u2019s stop and think about the implications of that for a moment, but not for too long.\u00a0 The results certainly won\u2019t be pretty, especially if speed is involved.\u00a0 It\u2019s a wonder that the cops don\u2019t have random tyre pressure checks the same way they do random breath testing and random speed checks.\u00a0 Oops, maybe I shouldn\u2019t have written that \u2013 I might give them new ideas and new ways to milk our wallets.<\/p>\n

So how do you get those nice Baby Bear tyres that aren\u2019t too hard or too soft but just right, where you\u2019ve got enough friction to make the car handle well but not so much that your car guzzles petrol?<\/p>\n

The answer, of course, is to check your tyre pressure regularly.\u00a0 Some say that you should even check the pressure every time you fill up with fuel, but this may be going a bit too far.\u00a0 Maybe.\u00a0 Most modern vehicles are very, very nice to us and have tyre pressure monitors installed and provide us with an alert when the pressure strays out of the Goldilocks Zone.<\/p>\n

\"\"<\/p>\n

OK, so how do you know what pressure you should inflate your tyres to?\u00a0 The answer to that is usually provided very kindly by the car manufacturers, either in the owner\u2019s manual or on the door pillars (either on the driver\u2019s or the passenger\u2019s side).\u00a0 In my Volvo <\/a>\u00a0S70, the info is in the manual.\u00a0 In my Nissan <\/a>\u00a0Terrano, the information is on a sticker on the door pillar on the driver\u2019s side\u2026 unfortunately in Japanese where it hasn\u2019t totally faded away.\u00a0 Curses and naught words!\u00a0 Fortunately in situations like this, you can use online tools and good old Google to help you out (here\u2019s one possibility: http:\/\/www.tyre-pressures.com\/<\/a>).<\/p>\n

Tyre pressure, like porridge, can\u2019t be taken too hot.\u00a0 However, there is no such thing as too cold when it comes to measuring tyre pressure.\u00a0\u00a0 This is because heat makes the rubber a bit softer and the air inside take up a wee bit more space.<\/p>\n

When you check the tyre pressure, you need to be sure that you use the right units.\u00a0 Car tyre pressure is one of the few things that we still like to think about in Imperial units rather than metric (the others are height and the birth weight of babies).\u00a0 The Imperial unit is pounds per square inch (psi) but the metric equivalent is kiloPascals (kPA).\u00a0 The conversion formula is 1 psi = 6.8947 kPA, so if you use the wrong unit, you\u2019ll either be underinflated or overinflated by sixfold.<\/p>\n

Of course, getting Baby Bear tyres isn\u2019t as simple as that.\u00a0 If you\u2019ve got a heavier than normal load in your vehicle, this will press down on the tyres so they bulge out and get a Mama Bear tyre profile and will therefore act like a Mama Bear tyre.\u00a0 This really adds up to a beast with a big appetite, as the engine doesn\u2019t just have to cope with the extra load, it also has to cope with the extra friction if you don\u2019t increase the tyre pressure.\u00a0 And don\u2019t forget to make like Johnny Farnham and take the pressure down once you\u2019ve dropped off the load! \u00a0Oh yes \u2013 and make sure that your tyres aren\u2019t too worn or getting the pressure right won\u2019t do diddly-squat.<\/p>\n

To make things even more interesting, if you\u2019re into off-roading, you need to adjust the tyre pressure according to the surface you\u2019re driving on.\u00a0 In sand, for example, you need the extra friction, so Mama Bear might be able to help you out if you get stuck.<\/p>\n

Catch you later \u2013 I\u2019m off to check the tyre pressure in both cars.<\/p>\n

* This is not the name of a blonde model in the Goodyear equivalent of the Pirelli calendar. http:\/\/credit-n.ru\/offers-zaim\/vashi-dengi-zaim.html<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

  Getting the tyre pressure right is a bit of a Goldilocks process \u2013 it can\u2019t be too hard or too soft, but has to be just right.\u00a0 If you don\u2019t get it right, it could result in an accident that leaves you looking like you have indeed had an encounter with three grouchy, hungry […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[65],"tags":[],"class_list":["post-8112","post","type-post","status-publish","format-standard","hentry","category-safety-2"],"_links":{"self":[{"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/posts\/8112","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/comments?post=8112"}],"version-history":[{"count":2,"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/posts\/8112\/revisions"}],"predecessor-version":[{"id":11306,"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/posts\/8112\/revisions\/11306"}],"wp:attachment":[{"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/media?parent=8112"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/categories?post=8112"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.privatefleet.com.au\/blog\/wp-json\/wp\/v2\/tags?post=8112"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}