Why do we overlook our bike's most crucial component, its tyres?

Why do we overlook our bike's most crucial component, its tyres?
Hold your hand up if you've ever just pulled your bike out of the garage or shed, and set off without checking all's well. Automotive journalist Iain Macauley explores the topic further.

Good, so it's not just me putting my life in the hands of a matchbox-size contact area between bike and road surface - because I barely need say that's all there is between you and an at best embarrassing bike and gear scuffer, or, at worst, something to really ruin your biking day - or far longer.

Many of us assume that because the tyres are round, have tread and appear to be correctly inflated, then all's hunky-dory for a bit of ear-'oling on our classic.

But I had a squiggly moment on one of my bikes a few weeks back; at first I thought it was a puncture, but tyre pressure was good - then I noticed some almost imperceptible surface cracking on the rear round thing... and checked the age stamp.

It was ten years old, and it had gone hard. And it really didn't like 1000cc of Honda grunt.

Like most, I'm not a tyre tech expert, but it got me to thinking: what do we need to understand about our treads, especially if we've been short-sightedly trying to maintain all-important originality (for that, read "old bits"..) on our classics.

So I spoke to an expert, Ben Fields of Vintage Tyre Supplies in Beaulieu, Hampshire, and started by saying originality is key with classic bikes, then asking what are the risks in going to extremes and keeping original tyres on a bike - especially if it's going to be ridden?

"You can have originality and stay safe. New, period-correct tyres are available in the vast-majority of sizes to suit classic bikes of all eras," he said.

"On a bike you have a tyre footprint the size of a matchbox. That’s not a lot of grip in the first place. Add age and the inevitable hardening of the rubber and that weeny footprint is going to be useless in corners and under braking. And then you can add rain to the mix and see how you get on.

"I ride a bike most days - a 1981 BMW R65, the most practical and comfortable bike I've ever had. Riding is hazardous enough with all the other nonsense going on – you need everything working in your favour. And that starts with a bike in top condition from bars down to tyres.

"The natural and synthetic rubber elements harden with age. And it doesn’t matter if you store your bike out of the sun in a temperature-controlled garage, wrap it in cotton wool and sing it a lullaby at bedtime every night. The vulcanising process that formed the tyre in the first place continues unabated.

"At ten years old tyres will have reached a point of hardness that reduces their grip significantly, regardless of tread depth.

"Look at the date code (four numbers inside a lozenge shape on the sidewall that was adopted as a reference in 2000). The first two numbers are the week of manufacture, the second two are the year. So 2124 means a tyre was made in week 21 of 2024."

Before that there was a code, but it didn't tell you much.

I asked what can be the consequences of persisting with an old tyre for originality sake?

Ben replied: "Death or serious injury. Or maybe just an embarrassing face plant in front of your mates at a bike night if you’re lucky."

Can you maintain an original tyre, whether with products or a care regime, I added?

"No. You can make it shine with some tyre buff, but that doesn’t make it safe to use, regardless of tread depth.

"Tyres now made in period-correct patterns benefit from improved manufacturing processes and materials. They are superior to the originals for these reasons, and because they are new, supple and grippy.

"Tyres designed back in the day were made to suit the bikes and the roads of the day. Manufacturers then, as now, had a lot of input in the choice and spec of tyre.

"The suspension and steering set-up of older bikes is designed to work with tyres correct for that era.

"Customised or retro-modded classics often wear modern, larger rubber. From experience, most builders know exactly what they are up to and spec tyre size and type to match performance and handling upgrades.

"On the flip side, if you are eyeing a set of Avon Roadriders for your Bantam or similar, that would be overkill.

"I’d encourage all riders to be bike and tyre aware.

"Before I ride my bike I check safety-centric components from indicators to brakes and tyres. I accept that this circling of my machine probably makes me look like a nutter (or a dog doing that circling thing before retiring to its basket). No matter, when I ride off I know that everything is working in my favour.

"It’s a tough world out there for a motorcyclist, you have to give yourself every chance to survive. And that ethos very much applies to bikes that are ridden occasionally.

"Know the age of your tyres. Know their condition. Know their pressures and check them weekly. Always carry a foot or bicycle pump, a tube, a puncture repair kit and tyre levers.

"Tread depth means nothing if the rubber is old and hard. Most classic bike owners’ tyres will age out before they wear out. Change tyres at ten years old, sooner if you notice a drop off in grip. And if you’re not sure, see an expert company like Vintage Tyres, or your local classic expert; we'll give your tyres a check for free, as will, I'm sure, your local tyre expert."