Tyre selection: Choosing the best rubber for your wheels

I always try and get close to the best rubber I can find for my motorcycle. Not only do I find that a nice looking tread pattern can add street cred to your machine, but that picking the correct tyre for the type of riding you do can give you more confidence and make for a better overall ride.

Note: I will be concentrating on road bikes here with an emphasis on sports-tourers, super-sports and any other bike that fits in with the everyday urban/motorway riding scenario. No trackday tyres, off-road tyres etc.

Under pressure

Before we go in to anything about tread patterns and tyre sizes, the subject of tyre pressures needs to be addressed.

Correct tyre pressure (within a given range) needs to be maintained.

An over inflated tyre can lead to poor handling, suffer damage and wear unevenly. Equally, an under inflated tyre can also lead to poor handling (you can end up sliding the rear), suffer damage and wear unevenly. Additionally, an under inflated tyre costs you more as it takes more fuel to maintain the same speed.

On my CBR600F, I’m currently running 34psi on the front and 36psi on the rear; but check the manufacturers recommendations for your own machine.

Now to the fun bit…

Those magical numbers on the tyre sidewall

Ok, so you may see numbers on the side of the tyre similar to 170/60ZR-17 and wonder what they mean. They basically explain the dimensions of the tyre, what size rim it will fit and the speed it’s rated for (I’ll assume you already know the bit before the numbers is usually the make and model of the tyre…).

• 170 is the width of the tyre in millimetres
• 60 is percentage height of the side wall to the tyre width. So in this case, 60%
• 17 is the rim size the tyre is designed to fit. In this case, a 17 inch rim.
• R stands for radial (explained later)
• Z marks the maximum continuous speed rating for the tyre. In this example, Z indicates speeds in excess of 149mph (just read Z to mean very fast or 12 points and a ban).

As a side note, bikes tyre sizes are already optimised for the bike itself, so putting a 150/70 on the rim of a 130/80 spec’ed machine might look cool but could adversely affect the handling. If you do intend on changing tyre sizes, get in touch with the manufacturer or ask at sites like Visordown where someone else is likely to have done it already.

Compounds

This is where a bit of thought in selection comes in. A tyres compound is different depending on what the tyre is designed for. So, if you want a tyre that will last for ages you pick a hard compound tyre. Because the tyre is harder, it lasts longer. The downside to this is that you get less grip as the tyre has a harder time moulding to the surface of the road.

A soft compound tyre, on the othe hand, will provide better grip as the extra softness (like fabric conditioner) will help the tyre “stick” to the road better. The downside is that it’ll wear out - quickly.

So, if all you do is motorways everyday, the harder compound may make more economical sense at the expensive of a little performance. The softer compound, while wearing out quicker, should enable you to ride harder and get your need down with confidence.

Tread pattern

You can’t really tell too much with tread patterns. There are so many variations available that the only real difference is between the main categories of road and off-road (knobblies).

Radials vs. bias-ply

These are the two main tyre contruction types. In bias-ply tyres, the reinforcing fibres attached to the rubber are wrapped in an X type pattern. With radial, the fibres are wrapped perpendicular to the tread. The advantage here is that radials have more flexible side-walls and thus absorb road irregularities more. They also have a comparitively larger contact patch when lent over (which should give better traction like for like).

Certain rim profiles don’t accept radials and will only take plys so check your specs. You probably won’t notice any difference anyway (unless your a damn hot rider) so stick with the manufaturers recommendations.

Never mix your drinks

Even more so with tyre types: never mix radials with bias-plys; you’re asking for trouble and could get your backside in a lot of trouble.

Also, try and get tyres in pairs. Generally you should be able to go through two rears by the time your front wears, but try to get tyres that match. They’ll be designed to complement each other.

Finally…

When you do get new tyres, they’ll be slick from the manufacturing process and will need time to break in and get scruffy. Don’t think that burn-outs will help either. Just take it easy for at least the first 50 miles (if not 200). Many a rider has taken their pride and joy out of the shop only to dump its ass on the tarmac - too fast, too low, too soon.

Manufacturer links:

Bridgestone road tyre line

Pirelli tyre range

Avon tyre range

Metzeler tyre range

Dunlops tyre range (it took me about 10 minutes to work out the tyre models were at the bottom of the page…)