125cc go-karts are some of the most popular and some of the most fun to race. They’re good for beginners and more advanced racers alike, but you may be wondering what kind of top speeds 125cc go-karts can reach.
125cc karts typically reach top speeds of between 70 mph and 80 mph (113 to 129 kph). Weather conditions, track layout and tire usage will all affect the top speed of a go-kart on a track. Different levels of engine horsepower are another factor in the top speeds of these karts.
Below, we’ll go into more detail all about the top speeds of 125cc go-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.
5 Example Top Speeds Of 125cc Go-Karts
|CRG Black Wheel||Vortex Rok GP Engine||79 mph / 127 kph|
|Margay Brava 125||X125T Engine||76 mph / 122 kph|
|Tony-Kart Krypton 801R||Rotax Max EVO Engine||75 mph / 121 kph|
|Top Kart Twister||CRS Motori A1 Engine||74 mph / 119 kph|
|Righetti Gold Kart||IAME X30||72 mph / 116 kph|
As you can see, the differences between these five karts’ top speeds are relatively small, with most being within 1 or 2 mph of each other. The real stand-out is the CRG Black Wheel, with its Vortex Rok GP, and this is because the engine has 36 HP, whereas the others have considerably less (see below). In truth, the engine you choose matters more than the chassis, aside from some minor differences.
Some 125cc go-karts are made with 30 mm moly tubing which makes them a bit more lightweight than the 32 mm versions, but otherwise, the bare chassis is simply a structure for your engine that you can tune to make it go faster.
How Many Horsepower Does A 125cc Go-Kart Have?
|Vortex Rok GP||36 HP|
|Rotax Max EVO||30 HP|
|CRS Motori A1 Engine||30 HP|
|IAME X30||28 HP|
Having lower horsepower does of course correlate to a lower top speed, but horsepower isn’t everything. 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.
Tuning Your Engine
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 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 electronics and other more complicated systems, which isn’t exactly a typical mechanic’s best friend.
A couple of engines have cross-over to run in the same races, but most of the time races are separated by engine type to even the playing field. If you’re looking for the fastest around, 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 X30!
KEY POINTS• 125cc go-karts can typically reach top speeds of about 70-80 mph
• The main contributor to the kart’s top speed is its engine
• The fastest 125cc kart engine is the Vortex Rok GP
Are 125cc Go-Karts Safe?
125cc go-karts are safe, provided you have the right gear and understand safe driving practices. 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, it can still be dangerous if you don’t know what you’re doing.
Listen To Safety Briefings
No matter whether you’ve heard the driver briefing once or one million times, always pay attention to them before the start of a race or practice session. There’ll always be stuff you can learn in order to improve your driving and how to drive safer at that particular track.
Get The Right Safety Gear
Don’t skimp out on your safety gear. You need a race suit, SNELL certified helmet, race boots, and race gloves at 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 karting overalls for when the heavens open.
Wearing your safety gear, staying alert on track, learning everything you can about the kart, and generally remembering to respect the sport overall will help ensure you are safe when driving your 125cc go-kart.
What To Look For In A 125cc Go-Kart
Your Personal Preferences Matter
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 a simple lightweight chassis, while others want some extra features that can give you the edge in a race. 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!
Make Sure It Can Take A 125cc Engine!
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 between them, which can make all the difference at professional levels.
For example, 100cc-built kart chassis are almost all made with 30 mm moly tubing as standard to not weigh down the somewhat smaller, less powerful engine they’re supposed to run with. There won’t be 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 a brand with a location nearby, because getting spare parts will be far easier than always resorting to online shopping. That, and you can build up 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.
The Margay Brava 125
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 offering the ability to personalize your kart.
They’ll take your height and weight measurements and adjust the base kart chassis accordingly, something that you’d normally have to deal with yourself. As a newer manufacturer, Margay is always learning new ways of improving their chassis, and right now, they’re very competitive in the karting sector across the United States.
Flexibility In Engine Choice
Their 125 chassis is also compatible with any 125cc engine currently available on the market, and therefore it’s 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!
The top speed of a 125cc go-kart is usually around 70 to 80 mph, or 113 to 129 kph. A 125cc kart’s max speed will depend largely on what engine it’s using, as there can be a big difference in top speed when using an engine with 36 horsepower versus one with 28 horsepower.
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