Everybody’s heard of the popular 125cc go-karting race brackets, but the closely-related 100cc variation is lesser heard of throughout the karting world. However, its more manageable power and lighter kart chassis make it an ideal category for beginner adult drivers!
So, what is the top speed of a 100cc go-kart? 100cc go-karts can reach between 60 and 70mph. This heavily depends on track conditions, driver weight, engine type (2-cycle or 4-cycle) and a whole host of other variables.
Speed is exciting and important, but there’s more to karting overall that I think you’ll want to know! Things like what makes 2-cycle and 4-cycle engines different from one another, and how your enjoyment as a kart owner should always come first. Let’s jump into it, shall we?
Example Speeds Of 100cc Go-Karts
Although they’re only ball-park figures, it’s very handy to be able to look at a concrete number when thinking about speed potential. As such, I’ve scoured the current racing kart market and picked out a number of chassis with engines to match that’ll give you some insight into how fast these karts can go:
- Top Kart SR30.2, IAME KA100 Engine – 65mph
- BirelART RY30-S11, RoK Vortex VLR Engine – 68mph
- Margay Ignite K3, Honda GX100 Engine – 62mph
- Tony Kart Racer 401R, Yamaha KT100 Engine – 66mph
- CRG KT2, Honda GX100 Engine – 61mph
It’s quite easy to see the variation between these karts, but otherwise, they all fall within the parameters for top speed as I outlined before. There is quite a key difference between the biggest speed disparities, such as comparing the CRG chassis with the BirelART, and that comes down to engine cycles.
A 2-cycle engine only has two places that the piston inside will move to, and far less components. A single piston controls the whole combustion process, so they’re far lighter than a 4-cycle and can output power way faster. This is because it finishes the combustion quicker.
By comparison, a 4-cycle engine has multiple pistons (mostly two, but can be as many as four), and for combustion to occur it needs to have moved to four different positions. Due to this, speed is outputted in a more controlled way and on a more reliable basis than the somewhat plucky 2-cycle engines.
So, in spite of having more pistons and therefore what you’d assume to be higher capacity for speed, the 4-cycle simply displaces its power in smaller bursts. Lower top speeds, but more consistent run-times and a longer engine life.
Generally speaking, go-kart enthusiasts tend to prefer the punchier, more exciting 2-cycle engines for their rigs. However, having a 4-cycle engine has its own host of benefits ranging from longer lifespan and generally being more reliable.
Now, looking at the list above, it’s important for me to point out that the Honda GX100 is a 4-cycle engine and every other one is a 2-cycle. Even then, the IAME has lower horsepower than the RoK Vortex, so there are still notable speed differences in place between the 2-cycle engines of the bunch.
Top Speed Isn’t Everything!
Sure, going fast is definitely the name of the game when it comes to go-karting and motorsports in general. But when you own a go-kart, there are far more important things to worry about than what your top speed is!
I already pointed out that the IAME engine here has a lower horsepower output than the other 2-cycles, and yet these engines are still widely regarded as fan favorites the world over. This is largely due to how easy they are to maintain and how widespread race series are using these engines specifically.
When choosing a displacement for your engine, it’s important to do research and find out how many race series are running with that amount. For example, 125cc engines are popular throughout the United States and you’ll always be able to find races. 100cc engines are more niche, so make sure to check that out before committing to one.
This will then extend into which brand of engine you choose specifically. IAME, RoK Vortex, Yamaha and Honda will all belong to separate race brackets to keep the playing field as even as possible, so this means more research has to be done on this aspect, too.
Essentially, you’ll want to pick a widely used engine manufacturer as your engine of choice. Oftentimes, that isn’t the fastest one of the bunch!
Also remember that an engine is as much of a blank canvas as your chassis is when you first buy it. Over time, you can tune it and squeeze more top-line speed out of it than what’s listed here as I only looked as factory standard figures.
As somebody who loves high speeds and the thrill of it, especially since I’ve been racing karts since my 5th birthday, I understand why the top speed list would draw you to the fastest rig. But especially since I’ve been racing and seen both sides of the coin, you should absolutely weigh up all of your options first before setting your heart on something!
Why Choose a 100cc Kart?
It’s a pretty difficult question to answer, but I’m sure you’re all thinking about it. After all, 125cc is the biggest and most notorious category all around the world, so why should you pick the 100cc bracket to race in?
From personal experience, the 100cc engine displacement is perfect for adults who have yet to participate in go-kart activity yet want to jump into kart ownership; whether that be in racing, or generally enjoying practice sessions.
Most rental karts use either 60cc or 100cc engines as standard, and are typically limited to top speeds of 50mph. If you compare that to the unrestricted 100cc engines you’ll be buying for your own chassis, 60mph topping out at 70mph isn’t an astronomical step. Then look at 125cc which can hit up to 80mph… if I was new to karting, I’d definitely be intimidated by that!
It’s all about manageable steps, and this comes in different shapes and sizes for all people. Some enthusiasts really want the thrill of the 125cc scene and will jump right into it regardless of their past experience, and others would prefer to work their way up to that level.
As well as being a good category for adult beginner drivers, I also view 100cc as a great mid-progression stage for Cadet-level drivers. I covered this in a previous article, but typically 60cc is Cadet karting territory and after they turn 12, they jump straight into 125cc karts as Juniors.
If you have a Cadet-aged driver who doesn’t quite feel comfortable in the large step-up from 60cc karts, 100cc variants are a great way to prepare them and further hone their driving skills and confidence.
After all, at the top levels of Cadet racing, their karts would be near the 60mph mark as it is, so a smaller, more gradual progression with 100cc karts that start in the 60mph range can be preferable for some younger drivers.
In essence, you want to choose this category if any of the above applies to you. It’s a fun and plucky little bracket of racing that checks a lot of boxes for people, but just like 125cc for some, it isn’t for everybody nor is it accommodated in every area. Keep that in mind and I really hope that you can get involved with it!
What To Look For In A 100cc 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.
First and foremost, make sure to do plenty of research and find out which chassis are appropriate to be fitted with a 100cc engine. It isn’t so much whether the engine will fit in the provided space, but more-so whether it will be powerful enough for the chassis build.
Adult go-kart chassis are always built out of either 30mm moly tubing, or 32mm moly tubing. You always want to pick the 30mm tubing option if you want to have a 100cc engine, because it will be that little bit extra lightweight and therefore easier for your desired engine to propel it around the track.
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.
Otherwise, if you’re buying second-hand, ask to look under the kart to check out its wear plate. Go-kart chassis are made out of tubing and not much else, so it’s very important to make sure the tubes aren’t being worn down. A wear plate will see to that!
If the plate underneath looks good, you count on a structurally-sound kart. If the plate looks badly damaged, it might point to some hard wear on the tubes themselves.
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.
It has to be the Tony Kart Racer 401R, in large part due to my long-time admiration of Tony Kart racing pedigree but also the knowledge of their attention to detail in chassis-making.
The latest rendition of their Racer chassis has seen a whole host of upgrades, and it would feel like I’m owning a piece of history due to the 20 years that the Racer has been a huge facet of kart racing.
It is also a very flexible kart overall, because I could fit any of the 2-cycle engines I’ve previously mentioned to this chassis and go wild. On a personal level, I’d likely pick the IAME engine because I’m familiar with them as a whole, but the RoK Vortex is also an attractive engine due to the extra punch of power they possess.
The price of a brand-new chassis from Tony Kart is no small number, let me tell you that right now! However, it becomes worth every penny when you look back over the company history of World Karting Championship titles under their belt.
It’s the perfect kart for a dedicated racer.
There we have it! A look at five different karts with different engines, checking out the variations of speed you can achieve within the 100cc bracket. But, as I mentioned before, speed isn’t the be-all-and-end-all, because you can always tune an old favorite to compete with even the best of the best!