The Exciting World of Tyres!

6/22/2017

Apparently tyres are important. Who knew!? One thing that stands out significantly from my motorcycling courses was the alarming statistic that only a fist sized piece of rubber in each tyre is touching the ground at any point. Isn’t that staggering? For those keen cyclists amongst us, they’d be keen to point out that on their super-quick road-bikes they would get even less, perhaps a finger length? To which I’d respond, let me know when you’re doing 170km an hour in the Northern Territory, then and we’ll chat. However, tyres are important. Before writing this post, I had a basic understanding that tyres were black and round. That’s about it. Oh, and they work better if they’re pumped up. I don’t want to undersell my vast knowledge!

What is the Best 4x4 Tyre?

Well…it depends. What are you going to do with it? If you’re off shopping in a mall, then you don’t need large, deep-tread 4x4 tyres. These tyres will be noisy, heavy, slow you down and cost you more fuel. So I’ll cut to the chase straight away – there is no perfect tyre. There is only a perfect tyre for you and your vehicle…which sounds like a dating site. Let’s move on!

What driving am I doing? I don’t intend on doing a lot of off-roading, 80% will be on the highway, however, there will be tracks and trails I’ll generally jump down. For the most part there won’t be a great deal of snow, but occasionally I’ll be travelling at altitude where it could be cold and icey. If I can get tyres that don’t smash my mpg/kpl then that wold be lovely. I’d like my tyres to last as long as possible. . . who doesn’t?!
So from that, I would guess that a full-on sink-your-fists-into-the-tread tyre with a great deal of grip for handling mud-terrain is probably overkill. As too would a completely flat F1 tyre with as I’m not going to be racing. So somewhere in between that and I’ll be happy.

Generally your car will come with tyres, unless you stole it. Manufacturers will have some idea of the best tyre for that car and may, or may not, install them on it when you buy the car. So check what wheels and tyres are on the car in the beginning. They may be putting all-season tyres on them which will probably make-do for 90% of everyday travel. Larger tyres with larger grip will generally cost more.

Wheels

It’s generally accepted that car tyres fit on wheels. At the moment, this is 100% true. In the future there is the potential of a spherical wheel held together by magnets . . . but until 2050 comes, we’re stuck with boring old wheels! More on the spherical tyre though right here.

So then we have a choice of Tubeless or Split-Rim wheels. Before writing this post I had no idea what either did, so this is very much from the ground up. Split Rims are fairly simple: the wheel has two different components, the locking ring rim and the locking ring (pictures tell a thousand expletives, so check out the pic). The alternative is a tubeless rim where both lips on each side of the wheel are the same. It used to be that all vehicles would come with split rims because they’re easy to fix out in the bush (and probably because tubeless rims hadn’t been invented). From the numerous pictures you can see on Ministry of Defence Land Rovers or Landcruisers, or old Ambulances, or Mining vehicles, they all have the older tyres and wheels i.e. split rims.

More Interesting Facts About Rubber

For me, the chosen tyres will provide you the best grip, longest life, lowest rolling resistance i.e. so you get better miles per gallon with a tyre of less drag. Considering this blog is written in Australia, they may have different rules than the rest of the world when it comes to tyre ratings and specs. What is fairly universal is that each tyre company will have certain brands and names that will sway you one way or another: Mudcruncher; Rockwrestler; Other Harry Potter Characters; and even Lifesaver.

There is also the aspect of tubeless tyres vs non-tubeless, which touches very close to wheels as well, so there is a section on that here too. Pictures will help you (below), but essentially tyres in that case are exactly what they describe: they have no inner tube, and instead rely upon strength of the tyre to create a seal with the rims of the wheel. Tubed tyres generally come with split rims and an inner tube (like your pushbike). Tubeless Tyres are simpler, although a bugger to fix in the middle of nowhere. Most 4WDs on the road today are fitted with tubeless rims and radial tyres, which is probably where I am heading.

What Can It Possi-Ply Matter?

I will be looking for a tyre that is about 80% highway with some off-road capability. I believe most of where I’m going can be navigable by engaging the 4wd and diff-locks, and if really tasty, releasing the tyre pressure and driving slowly through whatever craggy mud slides are in my way. I did read that having tyres with more ply i.e. multiple layers (see diagram of radial vs cross-ply tyres) makes a stronger tyre, which makes sense. Radial tyres tend to be a bit weaker in the side walls, but you can assess the tyre itself to see what ply they are. 10-12 ply looks a pretty solid tyre. Back in Wales for the trip from London to Sydney (see book!) we grabbed an unknown brand called Matador who were kind enough to sponsor us – they were absolutely superb for the entire trip! And the best thing about this utterly faultless tyre? They cost nowhere near the same as the big brands, so don’t be fooled by the cost, look for the quality of the tyre in ply (if available) and what driving you’re actually going to do with them. The wider the tyre, the more grip but also the more drag. In most cases I probably won’t need 13 inch wide tyres when 8 inch will do. Additionally, if I can get 40,000 to 70,000 miles out of them, particularly the latter, then I’d be happy.

How To Read A Tyre

Jump onto a website with multiple tyres available, and you can usually fill out a web-form on the type of tyre you want – just to get the feel of what you’re looking at. This will however mean that you need to know some numbers…so what the hell do all those numbers mean?
Let’s look at the current tyre you have on. Generally they will take the form of something like 215/70R15, which may as well be a Star Trek Star Date. Captains Log, 215/70R15. . .

215 relates to the width of the tyre in millimetres – so 215 would be something like 8.4” wide tyre. The width of the tyre you’ll need will depend on the wheels of the car, unless you’re going to replace the wheels as well…then go for your life!
70 relates to the Aspect Ratio, in other words the percentage of the width that equals the height of the sidewall e.g. 215*0.7 means a sidewall of 150.5mm/6 inches
15, the last figure, relates to the Rim Diameter i.e. how big your actual wheel is. This is measured in inches just to keep you guessing between inches and millimetres. It’s at this point that you’re waiting for there to be another measurement but in furlongs.

Pumping my prospective Landcruiser into the https://www.jaxtyres.com.au spits out that I need a 750R16 . . . which to makes no sense whatsoever! I’m fairly sure I don’t have a 27inch tyre. It would be like driving a sausage roll! Naturally this takes a different measure and instead relies upon inches once again i.e. 7.5 inches wide on 16 inch rims. This would be a fairly thin tyre, with low drag but by no means an issue. Doing some searching (for not the top brands as they are firkin expensive!) I came across Toyo Tyres and something called a Highway Terrain tyre vs a Open Country, which come in at about $181Aus per tyre. There are even second-hand tyres out here that will probably cut your costs in half for some minimal tread on the tyre . . . this naturally sounds like a bloody minefield, but if you’re on a budget! Will keep you posted on how I go.