How Fast Do Go Karts Go? Top Speed by Class, Rental to KZ

By Alessio Lorandi, 2013 CIK-FIA World Champion, KF-Junior.

The short answer

Listen, it depends on what kart you are sitting in. A rental kart does about 50 to 75 km/h. A kart for a six year old can reach 100 km/h. A junior or a senior reaches 135, 140, even 150 km/h. So I will go class by class, with the numbers I have given myself on the podcast and in my book. And then I will tell you why the top speed alone tells you very little.

How fast do go karts go, class by class?

Here is the table. The km/h are my own numbers, the ones I have said out loud or written down. The mph is just a straight conversion of my km/h, rounded, so you don’t have to do it in your head. One row is not mine, the superkart, and I say where it comes from.

Every number depends on the track. A short track with no straight will never show you these speeds.

How fast do rental go karts go?

On a typical rental track you may go from 50 km/h top speed down to like 35 km/h minimum speed to make a hairpin. So you brake for 10, 15 metres and that’s it. The fastest rental karts, I believe, reach up to 75 km/h. I say “I believe” because that one is my estimate.

And it changes a lot between indoor and outdoor. You normally reach higher top speeds on the outdoor tracks, because indoors it’s hard to have a long straight where you pick up a lot of speed. I go through that in indoor karting vs outdoor karting.

To give you an idea of the gap. At South Garda Karting in Lonato, which is 1,200 metres, we normally do a 46, 47 seconds lap with a senior or a junior kart. In a rental kart on that same track you would be at least 20 seconds slower. I mean, they are not built for performance. They are built for fun.

The rest of that comparison, the costs and when to switch, is in rental karts vs owner karts.

How fast do kids’ go karts go?

Karts for six to eight year olds can reach up to 100, 105 km/h. That seems quite a lot for kids of that age. And to be honest, maybe yes. But at the end of the day, when you are going flat out on the straight at that speed, you don’t really feel it.

And you can limit it. You can change the coil, so the limiter of the engine comes down from say 14,000 rpm to 13,000 or even 12,000. Or you can increase the sprocket, so the final drive ratio, and that reduces the top speed. The safety side is in is karting safe for kids.

Then from eight to twelve they are in 60 Mini. In my book I use the mechanics’ hairpin at Lonato, turn 4, as the example: in a 60 Mini you reach it at 97 km/h. That is with 10 horsepower. So you see, the top speed of a small kart is closer to the big ones than a parent would guess. The difference between the classes is somewhere else, and I’ll come to it.

How fast do racing go karts go in juniors and seniors?

At Lonato, juniors and seniors reach 135, 140 km/h. In general the speed in karting gets up to 130, 140, 150 km/h. That’s a pretty considerable speed if you think that a junior kart weighs only 145 kilos including the driver. A senior OK is 150 kilos.

Between juniors and seniors the whole kart is exactly the same. There is a bit more power from the engine, and that’s about one second per lap. You almost don’t even notice it.

The biggest jump you will feel as a driver is from 60 Mini to juniors. I still remember the first day I drove a junior kart, a KF3 as it was called in 2011. So much power out of the corner. I was like, wow, this is like a Formula One.

If you are choosing a category now, the classes are in best beginner kart classes explained and the ages in the karting ladder from 6 to 16.

How fast is a KZ shifter kart?

A KZ is a 125 cc with a six speed gearbox, and it only has 52 horsepower. It doesn’t sound like much. But the first time you try it and you are not used to it, the power on the exits of the corners is just insane. So the ultimate top speed is not so high, but the power range at 10, 11,000 rpm is something else. It feels like being on a roller coaster all day. That is my Disneyland, by the way.

And it’s heavier. A KZ2 is 175 kilos and a KZ is 170, so 30 kilos more than a junior. With the gears the approaching speed is really high and the weight is really high, and that’s why a KZ has front brakes. Otherwise it just doesn’t stop.

How you drive it is a different topic, and it’s in my shifter kart driving tips.

How fast is a superkart?

This one is not my data, so I give you the source and nothing more. Wikipedia’s Superkart page gives a top speed of 250 km/h (155 mph) and 0 to 100 km/h in less than 3 seconds. That is far above every kart in the rest of this page.

Why does a go kart feel faster than the number?

Because in a kart you have no seat belts and you are literally sitting on the ground. Especially if you are a tall driver and you have to sit very low. There are no airbags and no carbon monocoque like in F1.

And then the g forces. You get up to 2.5 g in the corner laterally, and about 1 g in longitudinal. Your heartbeat is at about 178, 180 for a 15, 20 minute session. People think it’s not a physical sport. It’s a proper workout.

I believe the hardest skill at the start is exactly this, sensing the speed. We are not designed to drive at 150 km/h on a four-wheel machine that weighs only 145 kilos in total. We are designed to walk on the ground. So the confidence in the speed is something you have to build.

How hard does a go kart brake from top speed?

Here is where the classes are really different. In a rental you slow down 15 km/h for a hairpin. In a professional kart you may go from 130 km/h all the way down to 50 km/h for a hairpin. So you have to lose 80 km/h, and you brake very hard for much longer.

In a 60 Mini, on the data, you aim at 1 g on the brakes. If there is not enough grip you get 0.8 g. In a KZ, because you have front brakes, you get easily up to 1.8 g. At the CIK-FIA world championship at Franciacorta I pulled 1.8, 1.9 g on the braking for turn 5 and for turn 13, the last hairpin. When the track is not grippy you are more at 1.6, 1.7 g.

And the slower the kart, the more a small mistake costs you. If you brake 7 metres too early at 300 km/h in Formula 2, at Variante 1 in Monza, you lose roughly half a tenth. If you brake 7 metres too early at 97 km/h in a 60 Mini, you lose up to 2 tenths. It’s always 7 metres.

Does top speed win races in karting?

No.

Drivers may say: “I have no top speed.” Then they come to see the data of their teammates, and their teammates maybe have even less top speed. Remember, mate, data doesn’t lie.

So where does top speed come from? From the corner before the straight. The whole goal of using the track is to keep up your RPMs. If you keep the RPMs up in the mid corner, you have more minimum speed and more exit speed. And ideally you can even drive with one sprocket less and have more top speed than everybody else around you. The drivers who do that are not genius. They are just using the track more than you, probably. The sprocket side is in driving one sprocket down explained.

In a 60 Mini you have 10 horsepower, so it’s all about momentum. If you gain half a tenth on the entry but you lose two on the exit because your RPMs are dead, that’s not a good trade. With more power it shifts. In a KZ the goal is to win more time on the entry and on the exit. You still want to carry quite a bit of minimum speed, come on. But the top speed number alone tells you very little.

Frequently asked questions

How fast do go karts go in mph?

From my own km/h numbers, converted straight to mph: a rental kart is around 31 mph on a typical rental track and up to about 47 mph, a kart for a six to eight year old can reach 62 to 65 mph, and juniors and seniors reach 84 to 87 mph at Lonato and up to about 93 mph.

How fast do rental go karts go?

On a typical rental track you may see 50 km/h top speed (31 mph, converted) and 35 km/h in a hairpin. I believe the fastest rental karts reach up to 75 km/h (47 mph, converted). Outdoor tracks give you more top speed than indoor ones because the straights are longer.

How fast does a kid’s go kart go?

Karts for six to eight year olds can reach 100 to 105 km/h (62 to 65 mph, converted). You can bring that down by changing the coil so the engine stops at 13,000 or 12,000 rpm and not 14,000, or by putting a bigger sprocket on the rear.

How fast do racing go karts go?

Juniors and seniors reach 135 to 140 km/h at South Garda Karting in Lonato (84 to 87 mph, converted), and the speed in karting gets up to 150 km/h (93 mph, converted). A junior kart weighs only 145 kilos including the driver.

Is top speed the most important thing in karting?

No. If you keep the RPMs up in the middle of the corner you have more minimum speed and more exit speed, and you can even drive with one sprocket less and have more top speed than everybody around you. The top speed comes from the corner before the straight.