When Are Hard Kart Tires Faster Than Soft? The Three Conditions

It may be the common rule to think that softer tires are always faster, and it's something most drivers refer to. And to be honest, if I didn't think about it, I would also say yes, they're always faster. But the reality is that on a few occasions they are not. On a few occasions, the harder tires can be faster.

Now, I guess that's quite crazy to say, but it's real. And think about it. One of the clearest examples of hard tires being quicker than soft tires was at the F1 2025 Imola Grand Prix. P1 and P2, Piastri and Verstappen, qualified on the softs. But Russell in P3, just one tenth away from Piastri, qualified on the mediums, which is quite unusual to see in a final run in Q3, where you try to get the maximum grip available.

The reason was that they were suffering on the softer tires. Even though it was just a single lap, they would overheat badly by sector three. The other teams managed to make the softs work. Russell and Mercedes couldn't, so they actually got faster by running the mediums. That was a clear example of what it means to choose mediums over softs.

Why softer tires are faster 90% of the time

As I said, 99% of the time softer tires are going to be quicker than harder tires, especially in very low grip conditions or in cold temperatures. When you're driving in the wet, for example, you're pretty much driving all the time in really cold temperatures for the tires, and so softer tires will always be better than harder tires.

What does a softer tire actually do? It switches on earlier, at lower temperatures. Cooler tire temperatures are good for soft tires and very bad for hard tires. You'll have way more grip on softer tires in cold conditions, because hard tires simply need way higher temperatures to be switched on. So in the wet, and in cold dry conditions, thinking about winter time, the softer tires have a huge advantage over the harder compounds.

A softer tire is switching on earlier, in lower temperatures. That's pretty much it.

That's why, unfortunately, there's this phenomenon of drivers treating the tires. I've heard it a lot in the UK, but it's a pretty worldwide spread phenomenon. They put some chemicals in the tires that make the compound softer, and it literally, instantly gives you one or two seconds of advantage, especially in those low grip conditions when it's cold or wet. People are risking getting disqualified in the attempt to soften up the tires.

Fortunately that's not the case in CIK-FIA races, or in WSK races, where there's parc fermé most rounds. You literally can't do anything to the tires, because they're held hostage at parc fermé, where you mount them. Not every organization can do that, in terms of logistics and storage. But I think that's something that needs to change in our sport. You're not allowed to change the tire compound, otherwise that's cheating, and even if you don't get caught, it's immoral. It's unsportsmanship at its purest.

And the pressure to treat tires is only growing, because compounds are getting harder and harder. Partly for cost savings, because harder compounds make tires cheaper in the end: the performance stays more consistent over a few laps and sessions, so you don't change them as often. And partly for ecological reasons, tires are getting more eco-friendly, and with that the compound becomes a bit harder here and there. With this double push it's now a pretty hard compound compared to what it used to be 15 years ago.

I remember we used to go to the south of Italy in the summer, tracks like Naples at Sarno, or La Conca, where there would be literally five centimeters of crest of tire grip layered on the track. Tires were super soft and you had unbelievable performance, especially on new tires. Now it's impossible to see that, unless they're putting resin on the track, or there's a new surface that creates that sort of grip crest. But it's very unusual nowadays.

So since you can't change the compound, it's at least good for drivers, mechanics and coaches to be aware of the differences, and of when one tire compound makes a big difference versus another. I went through the basics, why compounds differ, why unused old tires get slower, and how driver height changes which tire suits you, in the soft vs hard explainer on Senndit. Here I want to focus on the three occasions where the softer tire is not the faster one.

Reason one: the track is above 60°C

If the track temperatures are extremely high, the hard tires are going to be pretty good and the soft tires are going to struggle, because they overheat. Soft tires do not like the hot tire temperatures that come from hot track temperatures.

If I had to give you some random numbers: a soft compound like a LeCont might have a maximum temperature range of about 90°C, whereas for MG tires the optimal operating range is about 100°C. So there's at least 10 to 15 degrees between the two. At 100 degrees the MG tires are going to thrive, whereas at 90 degrees the LeCont tires are going to struggle. That's literally the intersection point where the soft tire starts struggling and the hard tire starts performing better.

Unfortunately it's not just about the compound. If it were the same brand, LeCont super soft against LeCont soft, or soft against medium, it would be quite straightforward. But there are a lot of factors that differentiate tire brands, so we can't compare apples to apples. Let's pretend we had the same brand and were just comparing soft against medium.

The medium is faster when the soft struggles, and that's when the track temps are extremely high, above 60 degrees. By the way, in the summer of 2026 we had way too many days with track temperatures above 60 degrees. It was insane. When the air temperature was 40 and it was sunny, the track would easily go above 60 to 65°C.

If you put your tires on the ground without putting any friction or effort through them, they'd already be at 65 degrees Celsius. That's the optimal operating range on a winter day in January.

So straight out of the gate you'd feel the grip. But then that grip fades away as you drive, especially if you drive aggressively, by your driving, by the setup, or both. You'd do one or two crazy fast laps with the soft tires and then you'd see the times dropping off.

With the mediums, with harder compounds, you'd still struggle the first two or three laps, but compared to winter time you'd be a lot better off in those early laps. And then the good thing is the consistency. Those tires hold on during the session, even improving, I would say. At 105 or 110 degrees of tire temperature they're still going to thrive, whereas the super soft tires are literally falling down a cliff because of the overheating.

That drop-off is the signature to look for in your own lap times. It's the same stint shape I describe in the tire pressure method: fast first laps, then a slide backwards while everyone else is improving.

Reason two: an abrasive track, plus the heat

The second reason is the degradation factor, which depends a lot on how abrasive the track surface is. But again, it's highly correlated to track temperature. If the track is very abrasive but the temperatures are cold, say February or March in the northern hemisphere, in Europe, where it's still low temperatures, then you won't have that much degradation. You will have it if you match a high degradation surface with high tire and track temperatures.

That's literally the deadly combo for any tire, but specifically for soft tires.

Abrasiveness comes down to the particles that make the track surface, the little stones within it. A brand new track is not that abrasive. A track that's very old starts to be more abrasive. That's a very simple rule of thumb, and it comes down to so many things that I don't have the full knowledge about, so I won't even try to explain it.

But you'll see it. On some tracks your tires last forever, for days. On other tracks, even though the track temperature is the same, the tires last just a few sessions and then they're completely cooked. On those high abrasion tracks, matched with high track temperatures, the soft tires are going to struggle massively. Maybe over one lap they still perform very well. But then again, what's your real goal?

Reason three: one lap, or 25 laps?

When we ask whether soft tires are faster than hard tires, do we mean over a one-lap pace, or over a 25-lap race? Because that's the point. 99% of the time, softer tires are going to be faster than mediums or hards over a one-lap qualifying pace. That's obvious. Even if the tires are overheating at some point, you'll still get a peak performance that's higher than a harder compound.

But if we're talking about a 25-lap race, you don't care that much about peak performance. You care about consistency. You don't want to be really fast on lap one and two and then struggle for the other 23 laps.

Do we mean over one lap, or over a 25-lap race? Because that's the point.

So it comes down to understanding the actual goal of the session, qualifying or race. And when you have a lot of degradation, you have to play around with the setup and the tire pressures, and the driving has to be smoother than it would be on a harder compound.

That's the third aspect: the mileage you need to do on those tires. If you're planning to do five laps max in qualifying and then throw them away, softer tires are going to be faster 90% of the time. But over a high number of laps in a whole race, I'm pretty sure that in many cases, with high track temperatures on an abrasive track, the medium or hard compounds will perform better over the whole stint than the soft tires. How well you hold your pace across a stint is exactly what lap-to-lap consistency measures.

At the end of the day, though, this is a curiosity guide. There's nothing you can really do about it, because when you go racing in karting you can't select the compound you want. They give you tires, and that's what you race on. So it's pure curiosity for kart addicts like myself, and probably like yourself. You can't overthink it. But it's good to have an idea of what each compound does in different conditions.

The part nobody talks about: whose rubber are you driving on?

Finally, I want to remind you of one thing. It's not just about the tires you have on. It's also about the track conditions you're driving in, in terms of grip level. Let me explain.

Say you're driving at a race weekend where every single driver on the track is running very hard compounds, like the Maxxis used on the Tillotson T4 karts. Then the track is basically going to be rubbish in terms of grip. It's going to be very slippery, because those tires are so hard that they're laying down a layer of very low grip, versus a super soft compound like a LeCont.

So if, during that weekend where everybody is running on Maxxis, you show up with extremely soft tires like LeConts and expect to set the track record, you'll probably be disappointed. If the track is a disaster in terms of grip level, you can't erase that by putting super soft tires on. If the surface is slippery because of a grip layer from super hard tires, rental kart tires basically, then no matter what soft tires you put on, you're still going to be sliding like crazy.

Take those races in Italy that run together with the Tillotson T4s. The session that drives right behind them in the schedule, even on soft tires, is going to be super slow compared to their normal lap times without the Maxxis karts on the track. It comes down to what layer of rubber you're driving on. And that levels the playing field a lot between who has soft tires and who has harder tires. In that moment it doesn't matter too much whether you have super softs or just mediums.

I really mean it. Many times I was quite upset, because I was like, okay, I'm going to get a super fast lap time now, I'll show you. Then you go out on those soft tires and nothing really changed, even though this tire is supposed to be way faster.

A super soft tire gives you a really quick lap time if the rest of the drivers on the track are also driving on that same rubber.

That's why the very few times the track was exceptionally fast, with track records, like at the FIA World Championship at Franciacorta, it was because everybody was running on LeConts, basically the softest tires you can run. You had a track layered with the highest grip tires in the world, so you were hitting the fastest laps in the world just by driving on it. Even at 50% effort you'd still go way faster than when the track was slippery because other categories, or even your own, were driving on bad tires. It's the same mechanism as track grip evolution across a race day, just driven by the compound instead of the clock.

So whenever you go driving, always see what the other drivers are on. That's basically what I do, 24/7. When I go testing on a random day, I try, almost in a sneaky way, to look at every single driver, even if it's just 20 drivers on the track. How many are on LeConts, on soft tires? How many on Maxxis? How many on MG, how many on Vega? I want to have an idea, and ideally I drive together with the drivers that have the soft tires. It's part of being a grip hunter.

At South Garda Karting in Lonato, for example, there's open pit lane for 45 minutes every hour, so you can choose when to go out. The best thing in my case is to go out together with the drivers that have similar tires to me, so at least I get a pretty high grip level, even though the drivers with the worst compounds are going to go out after. I don't want to overcomplicate it. It's an anecdote, a funny story I like to tell. But it comes down to who you're driving with at that specific time, and what rubber is being laid down. That's the story for another day.

La Conca, back to back: Vega one week, MG the next

To wrap up: 99% of the time the softer tires are going to be quicker, especially in low grip conditions, in wet weather, and in really cold conditions, because soft tires switch on extremely fast compared to mediums or hards, which require a lot more temperature. The first laps are going to be a shocking difference between the softs and the mediums.

But if you find conditions where the track is super abrasive, and you match it with track temperatures above 65°C, which is very likely in a European summer, then you're going to see some crazy things, where the softs are actually slower than the mediums. I've seen it multiple times between Vegas and MGs.

I remember a back-to-back at La Conca in 60 Mini. One race was WSK with Vega, and the next race, literally the week after, was with MG. Surprisingly, the week after on MG tires we drove three or four tenths quicker than the weekend before. With the Vegas it was the first two laps and then the lap times dropped quite dramatically. With the MGs the lap times kept getting faster every single lap, and eventually it was quicker overall in lap time and in race pace.

That was quite counterintuitive, because obviously Vegas are softer than MG tires. In that case we ran the MG Reds as well as the Vega Reds in 60 Mini.

So it was quite unusual. But I guess the track temps were extremely high those two weekends, and the abrasiveness was also pretty high. That made the perfect storm where the soft tires performed worse than the harder compound. If you log your track temperature and your pressures next to the lap times, you'll be able to see the storm coming before it eats your race.

I hope you got some value out of it. Let me know how it feels, sign up to PURPL, or join my Senndit six-month training community. I'll see you.