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What Is The Top Speed Of A 125cc Go-Kart? 5 Karts Reviewed

One of the most popular engine classes, 125cc is a fun and exciting way to race! Over the course of this article, I’ll be looking at the average top speeds of five different go-karts perfect for racing in this category and discussing all kinds of other nuances that you might not have considered.

So, what is the top speed of a 125cc go-kart? 125cc karts typically reach between 70mph and 80mph. Weather conditions, track layout and tire usage will all contribute to the speed of a go-kart on a track. Different levels of engine horsepower are another factor in the top speeds of these karts.

As well as discussing five different go-karts and their maximum speeds, I’ll be covering other topics such as kart safety, features to look for in a go-kart and, lastly, which go-kart I’d personally pick. To hear the views of an avid kart racer with well over a decade of experience, keep reading!

Example Speeds of 125cc Go-Karts

Speed potential is nothing without concrete examples, right? Well, I’ve scoured the market and found five competitive go-karts that you’ll find racing at events and we’ll compare their top speeds for some perspective:

  • Tony-Kart Krypton 801R, Rotax Max EVO Engine – 75mph top speed
  • CRG Blackwheel, Vortex RoK GP Engine – 79mph top speed
  • Righetti Gold Kart, IAME X3072mph top speed
  • TopKart Twister, CRS Motori A1 Engine – 74mph top speed
  • Margay Brava 125, X125T Engine – 76mph top speed

As you can see, the differences between these five karts’ top speeds are relatively small; most being within 1 or 2 mph of each other. The real stand-out is the CRG Blackwheel with its Vortex RoK GP, and this is because the engine specifically has 36HP whereas the others have considerably less. In truth, the engine you choose matters more than the chassis save for some minor differences.

Some karts are made with 30mm moly tubing which makes them a bit more light-weight than the 32mm versions, but otherwise, the bare chassis are simply that; canvases for your engines and tuning adjustments to make them go fast!

How Many Horsepower Does A 125cc Go-Kart Have?

Some examples of the horsepower of a 125cc go-kart are:

  1. Vortex RoK GP = 36HP
  2. Rotax Max EVO = 30HP
  3. X125T = 30HP
  4. CRS Motori A1 Engine = 30HP
  5. IAME X30 = 28HP

Having lower horsepower does of course correlate to a lower top speed, but horsepower isn’t everything that it seems! For one, you can always tune and upgrade your base engine to produce more horsepower and allow it to go faster. It’s a complicated process, but if you fall in love with a particular engine, it’s always a labor of love to do this and very satisfying when you push the boundaries.

In terms of each engine being different, let’s take the X30 as an example. It may be the lowest horsepower engine of the bunch, but a lot of kart racers still love it and use it competitively in order to beat out people with the X125T! They can achieve this by tuning it, of course, to tease out 2 extra horsepower, and they choose to do so because of the engine itself.

The IAME X30 is famous for being one of the cheapest kart engines to maintain, and one of the most reliable ones on the market. It’s also exceedingly easy to work on with its mechanical workings being more familiar to most drivers. Compare this to the Rotax Max EVO, which is primarily powered by electrics and other more complicated systems, which isn’t exactly a typical mechanic’s best friend.

So although every engine has its own horsepower and therefore top speed, you as the kart owner/driver will be choosing based on your experience and also, which kart racing class you wish to enter.

A couple of engines have cross-over to run in the same races, but mostly, everything is separated by engine to even the playing field. If you’re looking for the fastest of the fast, the RoK GP is certainly the class to choose, but if you’re after something a bit simpler yet still fun, you’ll never go wrong with the reliable ol’ X30!

Is Go-Karting Safe?

Any sport or hobby comes with its own host of risks, and it’s very important to remember that while go-karting is a lot of fun, there’s an engine involved and because of that, there are a lot of hazards to be aware of. That isn’t to say that karting isn’t safe, because with the right equipment and proper education, it’ll be just as safe as any other past-time!

Below is a sort of master-list of tips that you should remember to keep go-karting as safe as humanly possible:

  • Important Briefings: No matter whether you’ve heard the driver briefing once or one million times, always pay attention before the start of a race or practice session to listen! There’ll always be stuff you can learn in order to improve your driving and how to drive safer.
  • The Whole Package: Don’t skimp out on your safety gear. You need a race suit, SNELL authorized helmet, race boots and race gloves as an absolute minimum. I’d recommend getting a rib protector simply for comfort purposes over long races, and you should invest in a set of wet-weather overalls for when the heavens open.
  • Handle with Care: Practicing proper lifting techniques will protect your back and, most importantly, your limbs! The last thing you want is to get burnt when moving your kart after a race, so use some patience and wait before putting hands on the kart.

The true moral of this story is that go-karting can be dangerous simply because it’s a motorized sport. But that doesn’t mean it’s unsafe!

Wearing your safety gear, staying alert on track, learning everything you can about the kart and generally remembering to respect the sport overall will count for so much more than simply shying away from it all. In over ten years spent go-karting, I’ve only picked up one minor injury!

What To Look For In A 125cc Go-Kart

This is quite the tricky thing to offer advice on because picking your own rig is a highly personal process. Some people are looking for entirely lightweight chassis, others want some cutting-edge features that can give an edge in a race, and all sorts else. Even differences in the chassis tubing can be a big decision to make, and there’s only two types to choose from for 125cc go-karts!

The biggest thing to look for in a kart chassis above all else is whether it has the ability to be fitted with a 125cc engine. Although chassis are all very standardized in size when they reach adult classifications, there are some minute differences which can make all the difference at professional levels.

For example, 100cc-built kart chassis are almost all made with 30mm moly tubing as standard to not weigh down the somewhat smaller, less powerful engine they’re supposed to run with. Size-wise, too, there won’t be as much room for a more powerful engine if you choose a kart that’s supposed to function with a smaller cc engine.

More than anything, do some research on which kart manufacturers and dealers are located nearby. Look into the company’s background and what they focus on when making their karts for the general public.

It’s important to pick a chassis made by somebody who has a location nearby, because getting spare parts will be far easier than always resorting to online guessing games! That, and you can get a rapport with people in your area to help fix issues or otherwise geek out about your kart, which is all part of the fun.

What Kart Would I Purchase?

I chose the lineup of karts not only for a good comparison of top speeds, but also because they’re all models that I’d happily pick up for myself! Of the group, however, there’s one that stands out from the rest for me as an experienced, fun-seeking kart racer.

For where I’m living right now on the west coast of the US, the Margay Brava 125 is a pretty easy choice for me from a practicality standpoint. But there’s so much more beyond that! Margay has a great reputation as a manufacturer for providing race-ready packages, and the ability to personalize the karts they make for the buyer.

They’ll take your height and weight measurements and adjust the base kart chassis accordingly; something that you’d normally have to scramble with for yourself. As a newer manufacturer overall, Margay is always learning new ways of improving their chassis and right now, they’re very competitive in the karting sector across the States.

The 125 chassis is also compatible with any 125cc engine currently available on the market, and therefore makes it one of the most flexible of the bunch (as an example, Tony Karts are often raced with Rotax engines more than any other).

It’s a bit more on the expensive side in terms of brand-new purchase, but it still isn’t as pricy as a Tony-Kart chassis. Maybe I’m a sucker for up-and-comers, or options that are a bit out of left-field, but the design and overall attention to detail with the Margay Brava cinches it for me as a great pick!

Final Thoughts

There we have it! A look at five different karts with different engines, checking out the variables of speed you can achieve within the 125cc bracket. But, as I mentioned before, speed isn’t the be-all-end-all, because you can always tune an old favorite to compete with even the best of the best!

I hope that this article has cleared up some questions that you had about 125cc go-karts, and that it’ll serve as the catalyst to buy one for yourself to join my favorite category of kart racing.