Read Your Rubbers
Tyres miraculously keep your bike upright, pointed in the right direction and are a super-important to stop you falling off. Reading tyre wear patterns is a skill worth learning, so you know what’s going on, down below, whether you’re a weekend, highway-warrior, daily commuter or adventure gal…
There are all sorts of other important technical stuff they do as well, like help with the overall performance of the bike and suspension, to name just a couple, however this article will give you a brief idea regarding road tyres and how to keep an eye out, to keep you safe, to extend the wear of your rubbers and a little info on how to read all the coding guff on the side walls…
If there are any noticeably strange wear patterns that you don’t pick up with your checks, then your service technician should.
Tyre technology nowadays enable bikes to accelerate quicker, brake safer and harder… and lean insanely lower than ever before. Keeping an eye on your tyre wear patterns will assist with this, without throwing you off unexpectedly.
Air pressure is super important… always check your manual for the correct psi for your specific model. If you have too much or too little pressure, the signs will show up near the edges of your rear tyre.
If you see deep, rough and scratched tears on the circumference and you can just about peel back a large section to see deeper into the rubber, it could suggest there’s been too much air pressure put in.
If there are more conformed lines which curve to the centre of the tyre and there’s a scallop like tearing, then this would suggest your tyres need more air. These tears will look finer than the overinflated scenario.
If there are suspension issues with your bike, this can also influence the wear, showing up as uneven or wavy pattern, possibly indicating compression damping issues. Changing patterns are of concern and can indicate bad suspension settings, but to diagnose correctly, it’s best to have an experience motorcycle tyre fitter take a closer look.
For longevity, and even-wear, give your tyres a variety of cornering and highways and always, keep an eye on your tyre pressures. For the tread to be legal and safe, look for the wear indicator to show how much tread is left. This will be a blob of rubber, located in the middle of the tread cut. If it looks flush with the tyre, then it’s a goner.
If you’re lucky enough to be able to do a burn out, at the place you’re having your new tyre fitted, or someone can take the wheel off afterwards, then lucky you… a bit of fun before it goes to the tyre graveyard, but a flush wear indicator, is definitely illegal to ride and dangerous, which, if in an accident, very doubtful your insurance will cover you… which could be a costly mistake, especially if you’re liable and are sued. Don’t mean to sound doom and gloom there, but tyres are serious business, so need to be respected, looked after and renewed before they become unfit for purpose.
So… what are all those numbers and letters about, on the side walls of your tyres?
A typical bike tyre might read 180/50ZR-17 M/C, which is an international standard of writing the details onto a tyre.
There will be other combinations on tyres, especially for quads and trikes, for example, but I’ll just be discussing here, the generic international codes, worth knowing.
180 is the width of the tyre in millimetres, at its widest part.
50 relates to the profile of the tyre from the rim to the outer edge, expressed as a percentage, of the width of the tyre.
Off-road and adventure tyres often have higher profiles and sports and custom tyres will be really low. The profile influences the tyre’s curvature impacting contact with the road.
The first letter, Z, refers to the maximum speed the tyre should be used at maximum load and inflation, Z being anything above 240 km/h with no top speed limit. Whohooooo… There is a list available with internationally recognised speed ratings, but generally if you stick to the manufacturer’s recommended tyre, for your bike and the speed your bike can comfortably do, without blowing a gasket, then all should be pretty sweet.
The letter R refers to the tyre’s construction type:
- B for belted, which are reinforced for extra strength and load with materials like Kevlar
- R for radial
17 is referring to the wheel rim size, in inches. So we have a 17 inch wheel, 180 mm wide… yep, going to leave that one right there…
The M/C stands for motorcycle… that was an easy one.
Sometimes you’ll also see TT for tubed tyre and TL for tubeless.
Check around the tyre for some more really cool codes, like 4919 or 1918… they refer to the manufacture date, which is an important number to check because rubber perishes with age, especially if not used.
4919 is the 49th week in 2019 and 1918, the 19th week of 2018, the first two numbers being the week and the last two the year.
You should also see a little arrow… which indicates the rotation direction. After you’ve had new tyres fitted, check this arrow before leaving the shop; there have been times where this has been stuffed up, by human error and it’s dangerous to ride that way.
There may be other letters and numbers, but we’ve covered the main ones here to give you a general understanding.
Look after your rubbers and they will look after you…
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Thank you for your support,
Madam Rider xx