Everyone knows that they are round and black, but only we motorcyclists know how important it is to know everything about the tyres on our motorcycle. Tyres provide the direct connection between the motorcycle-driver and the natural environment: the tarmac (in this case). The efficiency of every component in the vehicle depends on what we choose. We can have a perfectly tuned motorcycle, but if we just ignore a detail involving coverage, our driving experience can easily become a nightmare.
First and foremost the“ABC”:
“Knowing how to “read” tyres is the first step in knowing how to choose them. In addition to the product name and country of production, each one also carries the specifications, which must reflect the type approval category stated on the registration certificate.
Generally, a string similar to this represents the size of road tyres:
“ 120/70 R 17 (58W) TL “.
Where “120” describes the width of the total contact surface area of the tyre in millimetres, whereas the “70” is the ratio between the height of the section of the tyre and the cord (therefore 70% of 120 = 84mm).
“R” represents the architecture, in this case, specifying a tyre with a radial arrangement to the treads.
“17” is the diameter of the rim in inches.
“(58W)” comprises two characteristics: the number corresponds to the load index (can go up to 120 for loads of 1,400 kg), the letter in the alphabet represents the speed category: the scale is broad, but it is important to know that “V” goes from 210 to 240 Km/h, “W” from 240 to 270 Km/h and “(W)” over 270 Km/h.
Another thing to pay attention to, especially when buying a set of tyres, is the so-called “DOT”, a 4-figure number representing the week of production in the year that reads as follows: e.g. “DOT 0117” = 01 (first week) 17 (in 2017). We recommend never buying tyres that are more than 2 years old.
Tell me how you ride, and I’ll tell you which tyre to use
We can call it identity, temperament or simply usage, but the tyre models on the market have it all, and when we set out to buy them, we must be conscious that they should reflect the use we intend making of our motorcycle. It’s a question of enjoyment, safety and most certainly our “back pocket”.
It’s self-evident, but it’s true: tyres are the shoes of our motorcycle, and as such, it’s difficult if not impossible, to find one pair that is suited to every occasion. From touring to the track, the range of uses is extremely broad, and manufacturers are usually quite clear in clarifying this for each model. Recently research in technology has produced good “crossover” tyres, which combine various requirements making them very versatile. Nonetheless, the characteristics defining the personality of tyre models are quite specific and important to know.
(Mix)ed, not stirred
It’s not James Bond’s vodka martini we are referring to. “Mix” is the jargon used to refer to the tyre’s chemical composition, which is basically pretty similar to a cocktail: on the inside are various elements including rubber and silicone, which according to the mix, are referred to generally as a soft or hard mix. The former generally guarantees greater traction whereas the second ensures more uniform wear and tear and higher kilometres. A short cover that manufacturers are trying to extend, by offering a multi-mix cover for example. These covers have different longitudinal strips of mixes (from 2 to 4, but who knows what the future holds), arranged symmetrically, starting from the hardest in the centre outwards to the softest. This format guarantees higher kilometres ratings for those of us not making mixed usage of the motorcycle, especially on highway surfaces where the harder central mix “works”, thus limiting the tiresome “grooving” on the profile and typical overheating, with consequent excess deterioration in the soft part, which comes into play when we use the shoulder, thus guaranteeing optimum lean angles in complete safety.
Notching or no notching?
Tyres are also distinguished according to the grooves on the surface area and once again, the choice will depend on whether the motorcycle is a sporting model or not. Touring tyres manage to drain water on the tarmac more effectively thanks to the notching. It is worth keeping in mind however that the endurance based “inlays” are something else altogether. They are no great help on the tarmac, in fact they are often actually dangerous on a slippery surface and tend to wear down quicker on the dry; they certainly make a good showing on many specials, but let’s keep this in mind.
Looking at their profile
They don’t all have the same shape. Each tyre model has a specific profile that lends itself to a unique drive: a “pointy” tyre can help with taking and changing direction, but a “rounder” one could improve stability with speed. The important thing is not to ever “mix them”: front and back tyres of the same model are designed to work together. You should also never install different products at the same time, even if they are the same brand.
How many km do you get? Yes, but how?
The TWI (Tread Wear Indicator) is what we need to keep an eye on to understand whether our tyre is wearing out. This refers to transversal lines on the profile that show the remaining depth of around 0.8-1.0 mm. If we consider that the minimum thickness limit according to Italian Road regulations is 1 mm, it is worth checking on this often.
But that’s not all: wear and tear and deteriorating performance go hand in hand. In other words, the specific performance level we get with the initial km from our tyres cannot be guaranteed down to the last: we also see this in Motorcycle GPs. What happens there in half an hour is what we experience over months or years, but the principle is the same.
When we are replacing tyres with new ones the golden rule applies to the profile: changing the front and back at the same time is always the right choice. Even if one of the two still has some tread left, it will have a very different shape from when it left the factory, and from its mate that we are about to fit; and take care with the first few metres after you’ve just left the tyre dealer! The protective wax that they are stored with takes a bit of time to wear off, and could result in some figure-skating before it is eliminated.
Pressure and temperature
Pumping up the tyres may seem like a minor detail, but it can make the difference between enjoying yourself and having a terrible experience. How many times have we ridden for km and km on our motorcycle, feeling that it “wasn’t our day”, to then discover that our tyres were at 1.5 bars? We need to check them often and use an instrument with a reliable setting. The correct settings are provided by mother Moto Guzzi and the individual tyre manufacturers. Why plural? Firstly because the front and back settings are different, and then because quite often, they differ according to whether we are riding solo or with a passenger.
Finally, we need to remember that the accurate pressure reading for road surfaces needs to be with cold tyres, because as we know, by heating up, air increases in volume, providing a false reading.
With regard to temperature, the more sporty the tyre, the higher the ideal running temperature; for this reason, it is not recommended to use these in an urban environment, where the tyre does not have time to reach the optimal range, consequently becoming dangerous and wearing out quicker.
So in the end, which one should I choose?
Now that we have all the theory to make a rational choice for the tyres on our motorcycle, nothing remains but to move on to the practical and trust our understanding. Just like a pair of shoes, we will quickly realise whether they fit like a glove or whether they “are not right”. Sooner or later we will find our favourite, even if changing and experimenting with new models can provide some pleasant surprises.
And what about you, do you have a favourite tyre for your motorcycle? Comment below the article and share your experiences and feelings with our members of The Clan.
