Weather and Tyres: Getting it Right

For riders in the UK, the weather is a constant factor to take into consideration when a track day is on the horizon.

It is a factor for consideration simply because it is so changeable, and we will often have to deal with a whole manner of different weather situations, and in turn, variations of track surface condition.

What I want to do for you here is give you some sort of idea of what tyres are ideal for different conditions , such as when is it wet enough for wet weather tyres? Or rather, when is it too wet for dry/race tyres?

Unfortunately for you, there is no definitive line between the two to help you confidently make that decision, but I have a fair bit of experience dealing with Britain’s wonderfully changeable conditions, so here I would like to try and educate you to help you better make the correct decision regarding weather and tyres. I will also cover the ‘cold temperature misconception’.

If you’re someone who happens to live somewhere with a climate that has you waking up and going to sleep without seeing a cloud in the sky, well, you can just bugger off, nobody likes a show off! 😉

(I’m just kidding of course. I love you really)

Before we have a look at the first type of tyre, here are a couple of brief definitions, so we’re all on the same page.

Dry: Not wet. Pretty simple really. NEXT!

Damp: When I say damp, I mean that you can see there are damp patches where there are different shades of grey on the ground (usually on a drying track) but you’re not getting spray or other signs of water being picked up on the tyres of the bikes in front.

Wet: Spray, wet lines on tyres, lines being left on the track, standing water. Any indication that there is water built up on the track surface I would consider to be wet.

Ok, now that’s done let’s get onto the stuff that matters. We’ll start with everyone’s favourite type of tyre. Racing slicks!

Racing Slicks

Examples: Dunlop GP Racer D211 – Pirelli Diablo Supercorsa Slicks – Metzeler Racetec Slick

When to be used: Dry. Nothing but dry.

When I say slicks, I mean racing slicks with no tread pattern. These tyres are not road legal and are used solely on the track.

They are to be used in nothing but dry conditions, and when I say dry, I mean dry.

No damp patches. Nothing.

The only other thing to mention is if you have multiple sets of wheels and one of those sets has slicks on, don’t be too eager to get them back on after a wet period.

Some people see a dry racing line appearing and head out on slicks, but useless you are pinpoint accurate and very consistent, do you want take the chance of straying off the line even just a fraction and hitting a damp patch?

I would guess not.

Road Legal Race Tyres

Examples: Metzeler Racetec – Pirelli Diablo Supercorsa – Bridgestone R10

When to be used: Dry, but will survive in damp conditions.

Again, ideally they should be used in dry conditions, but they aren’t going to be as treacherous as racing slicks are when encountering a little bit of moisture.

In slightly damp conditions you certainly won’t have the same levels of grip and you need to back it off a fair bit, but I wouldn’t rush back in at the first sign of droplets.

I have had a fair few sessions out there on a damp (albeit drying) track, and it is a fantastic lesson on what lack of grip feels like, and it does wonders for the confidence levels when it’s fully dry again, at which point you can really feel the grip.

(Note: While I say it’s beneficial, this is not something I would personally recommend because it’s not what they’re designed for.)

The line is drawn when you can see water being picked up by the tyre where it creates a damp line on it, or if you can see the tyre leaving a line on the track, you’re getting into standing water territory and should definitely head back to the paddock.

Hypersport Road Tyres

Examples: Pirelli Diablo Rosso Corsa – Bridgestone Battlax S20 – Michelin Pilot Power Pure

When to be used: Dry, and a bit of damp.

Whereas the above tyres are designed purely for the track, these are designed as a fast sport bike tyre that can handle a couple of track days.

They’re designed to last longer, so will have a harder compound which means performance will be marginally worse in the dry, but coupled with the extra tread will give better wet weather performance.

They should be able to handle a bit of moisture, but when you start seeing a fair bit of spray from the riders in front then you’re not going to be able to get the best out of them.

These tyre do however serve as a fantastic all round tyre, and I would say for novice, and even some intermediate riders, that you’ll have more than enough grip in the dry, with a bit of insurance if it starts raining.

And they’re cheaper too!

Sports Touring Tyres

Examples: Pirelli Angel GT – Bridgestone BATTLAX T30

When to be used: Dry and damp to wet track.

We’re continuing to move in the same direction here.

Sports touring tyres are going to be another step down in dry performance, but give better wet weather performance as a result.

Being that they are designed for all weather road use, they are going to be very capable on a wet track, while still allowing a decent amount of dry grip to have a little fun.

If it has been raining a lot and there is standing water everywhere, then there really is only one option for superb wet weather performance, which is…

Racing Wets

Examples: Pirelli Diablo Rain – Metzeler Racetec Rain

When to be used: Wet conditions

These are also not road legal tyres and are designed specifically for wet conditions on the track. As I said for the sports track tyres, when you see spray coming off of the tyres of the riding in front, you want to be on wets.

Proper racing wets are truly amazing, and although it does take a while to trust them when you can see nothing but wet track ahead, when you do, you will love them.

They obviously aren’t going to have the same level of grip on the brakes and throttle as dry tyres in the dry, but they are surprisingly good, and you can in fact get your knee down in the wet with wet racing tyres.

They will run in the dry, but it won’t take long for you to destroy them.

The Balancing Act

Now, the conditions aren’t always going to be perfectly clear cut, especially if you ride somewhere with a climate like Britain, or on a massive track where the weather can be different at two ends, so it’s up to you to make the right decision about what to opt for when the conditions are in-between.

Personally in the wet I like to go for something that is overkill, because I would rather overheat and wear them out quicker (i.e wets on a damp, drying track with wet patches in places) than crash on a tyre that wasn’t up to the job.

A wet tyre for example will work in the dry, but it will overheat quickly and destroy itself in little time. It’s your job to make the decision; do you sacrifice tyre life, do you chance crash, or do you sit one of two session out while the conditions move to a more easily determinable situation (fully wet or fully dry).

The Common Situation

What you find most track day riders have is dry tyres like racing slicks or road legal race tyres, and full wet racing tyres.

When it comes to conditions that are in-between i.e. damp and a little wet in places, riders will often choose the wets because it is the safest and most logical choice.

If you’re on a road bike maybe on sports touring tyres (like those above) then you get the best of all worlds because they will be usable across all conditions, albeit not to the same standards as dedicated dry or wet tyres.

Ambient Temperatures

It is a common misconception that the colder the temperature, the softer your tyre compound should be.

On the face of it, this makes sense, because a softer compound gets up to temperature quicker so it would be more beneficial in colder temperatures.

However, when we talk about a tyre coming up to ‘operating temperature’ this means that the tyre surface AND the carcass of the tyre coming up to a temperature to allow for best performance.

What happens when you throw on a super soft compound in the cold is the surface heats up very quickly, but the carcass doesn’t, leading to some nasty wear patterns and tearing.

A harder compound will not give you the same grip as a soft race tyre, but it will last a whole lot longer and give you a much more consistent feel because it is able to reach its operating temperature.

This is mainly a message for riders using racing slicks, or soft compound race tyres like Metzeler’s Racetec Interact in K0 or K1 compound. For those using harder compound road legal track rubber (e.g. K2 or K3) or, even harder still, sporty road biased tyres, they should easily cope with lower temperatures – some tyre pressure changes would still be needed, however.

There’s a reason why there are so many variations of tyre available today. Unfortunately there is no tyre that will have you running record pace at your favourite track, while giving you superb grip in the wet or low temperatures. We all know this.

I hope that the above has given you a good idea on what spec tyre will be ideal for the different weather conditions we have to deal with, in turn reducing any chances of you getting caught out with less than ideal grip levels (if you haven’t already, that is!)

Photo by JPC24M