The performance on a wet weather race tyre is absolutely staggering, allowing riders to lap within just a few seconds of the dry race pace on a soaking wet track.
In the previous issue of Fast Bikes Magazine, they spoke to the team at Pirelli who explained some of the key points riders need to know about wet race rubber!
- What Make A Full On Race Wet?
Well, two things. Firstly the tread grooves, which are designed to clear as much water as possible, while also giving the widest possible contact patch. Secondly the 100% silica compound, which can offer incredible amounts of grip even at lower temperatures.
- Are They Road Legal?
All Pirelli rain tyres are marked with an ‘NHS’ symbol, which stands for ‘Not for Highway Service’ so they can’t legally be used on the roads. The operating range is simply too narrow for use on a diverse range of road conditions.
- How Do They Grip?
The tyres have a way of conforming to any rough or uneven parts of the tarmac at a micro level, while also chemically bonding with any remaining water to ensure contact with the tarmac.
- Will They Work In The Dry?
They will indeed work in the dry, but due to the extremely narrow operating window, they will begin to deteriorate once a drying line appears on a circuit. That’s why you often see riders aiming for puddles if the weather begins to improve during a race.
- What Tech Do They Use?
Pirelli’s Diablo Rain tyres use a dedicated carcass and compound for the maximum level of grip in specific conditions.This has been developed and tested in World Superbikes.
- How Much Water Can They Shift?
From a theoretical standpoint, a rear tyre could shift as much as 8 to 10 litres of standing water per second at 200kph, although there are so many potential variables when it comes to a real world situation.
- Do You Need Warmers?
Rain tyres are capable of almost immediate warm-up due to their very soft compounds, and as such they are often used without warmers. Tyre warmers can be used just to keep the tyre temperatures close to their operation temperature of around 40°C – 60°C. Pressure from cold would need to be slightly lower than it would be at the ideal operating temperature.
- How Long Do They Last?
Rain tyres are designed to last for one full race. When conditions allow, some may consider using an SCR2 compound twice, but this does not happen often and is best avoided where possible. In general, when a rain tyre is at the end of it’s life, you’ll notice a significant drop in performance.
You can find out more about the Pirelli race tyre range here.
