{"id":79,"date":"2009-04-26T22:12:26","date_gmt":"2009-04-26T22:12:26","guid":{"rendered":"http:\/\/nobugs.org\/lejog\/?p=79"},"modified":"2009-04-26T22:12:35","modified_gmt":"2009-04-26T22:12:35","slug":"tyres","status":"publish","type":"post","link":"https:\/\/www.nobugs.org\/lejog\/?p=79","title":{"rendered":"Tyres"},"content":{"rendered":"<p>More high-geekery, this time related to tyres.\u00a0 By way of explanation, once I&#8217;ve finished the ride I&#8217;ll turn this blog into a set of &#8216;real&#8217; web pages and hence I&#8217;m dumping random technical content here too.<\/p>\n<p>When I bought my Courier Nexus bicycle from Edinburgh Bicycle Coop, it came with a set of tyres composed largely of soft cheese.\u00a0 The web says they were probably &#8216;Continental Sport Contact&#8217;.\u00a0 They barely survived a few weeks of the &#8216;ned diamonds&#8217; (broken glass) on my work commute, whereas the tyres I had on my previous bike (Schwalbe Marathons) had lasted ages without problem.\u00a0 So I switched them over to the Nexus and they&#8217;ve lasted 1.5 years so far.\u00a0 Awesomely reliable tyres, and I&#8217;d totally recommend them.<\/p>\n<p>So, coming up towards LEJOG I thought it might be a plan to put on a fresh set of tyres (as some kind of puncture insurance).\u00a0 But now that&#8217;s a whole new world of tech and numbers to grok.\u00a0 Once again, I&#8217;ll use the tyres I bought as an example &#8211; they were Schwalbe Marathon 40-559 26&#215;1.5 HS 368 kevlar guard <span id=\"r5-9\">50EPI with reflex side walls.\u00a0 Which all translates to:<\/span><\/p>\n<ul>\n<li><span><strong>Schwalbe<\/strong> &#8211; <a href=\"http:\/\/www.schwalbe.co.uk\/c2-1073-schwalbe-tires-marathon.html\">the company<\/a> who make them.<\/span><\/li>\n<li><span><strong>Marathon<\/strong> &#8211; their range which is designed for long life (rather than saving weight)<\/span><\/li>\n<li><span><strong>40-559<\/strong> &#8211; the ETRTO (European Tyre &amp; Rim Technical Organizations) standard designation for a tyre which has width 40mm and inner diameter of 559mm.\u00a0 All very precise and well defined (ish).<br \/>\n<\/span><\/li>\n<li><span><strong>26&#215;1.5&#8243;<\/strong> &#8211; the classic albeit fuzzy way of giving the size.\u00a0 26&#8243; is the tyre outer diameter and 1.5&#8243; is the width.<\/span><\/li>\n<li><span><strong>HS368<\/strong> is a particular tread pattern which Schwalbe do.\u00a0 You can find the same HS368 tread pattern on 28&#8243; tyres too, so they&#8217;d also be HS368&#8217;s.<\/span><\/li>\n<li><span><strong>Kevlar guard<\/strong> &#8211; underneath the rubber tread, there&#8217;s a layer of kevlar material &#8211; the same stuff they use in bullet-proof vests.\u00a0 This is insurance against punctures.<\/span><\/li>\n<li><span><strong>50EPI<\/strong> describes the weave of the tyre carcass &#8211; the inside bit that looks kinda like canvas.\u00a0 EPI is &#8216;ends per inch&#8217;, a measure of the density of the weave.\u00a0 There&#8217;s a tradeoff between strength, weight, puncture protection etc.\u00a0 Everyday tyres seem to be around 50, whereas race tyres (ie. weight-saving at all cost) are around 120.<\/span><\/li>\n<li><span>Finally, <strong>reflex sidewalls<\/strong> just mean that the sides of the tyre are kinda reflective, so that you&#8217;re more visible at night.<br \/>\n<\/span><\/li>\n<\/ul>\n<p>Schwalbe do an excrutiating detailed <a href=\"http:\/\/www.schwalbe.co.uk\/shopdata\/files\/TechInfo2-GB.pdf\">technical document<\/a> about all this stuff if you&#8217;re into that kinda thing.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>More high-geekery, this time related to tyres.\u00a0 By way of explanation, once I&#8217;ve finished the ride I&#8217;ll turn this blog into a set of &#8216;real&#8217; web pages and hence I&#8217;m dumping random technical content here too. When I bought my Courier Nexus bicycle from Edinburgh Bicycle Coop, it came with a set of tyres composed [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"_links":{"self":[{"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=\/wp\/v2\/posts\/79"}],"collection":[{"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=79"}],"version-history":[{"count":2,"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=\/wp\/v2\/posts\/79\/revisions"}],"predecessor-version":[{"id":81,"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=\/wp\/v2\/posts\/79\/revisions\/81"}],"wp:attachment":[{"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=79"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=79"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.nobugs.org\/lejog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=79"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}