When it comes to go-kart engines, there are many to choose from. But with so many options to choose from, you will often hear drivers mention these three manufacturers. Those being, Rotax, IAME, and ROK. All are good, reliable engines, however, each of them has their own strengths and weaknesses as well advantages and disadvantages. In this article, we will be looking into the Rotax engine. Made in Austria and introduced to the sport of karting in 1998, here are the pros and cons of the Rotax engine.
Pros: Cost Effective
The first thing that comes to mind when drivers hear the word Rotax is cheap. Basically, Rotax engines being cost effective is it’s defining quality as it is cheaper than its competitors like the IAME and ROK engines. Compared to its competitors, if you were to buy a Rotax engine that is fresh from the factory, you would be looking at around 3000-3500 USD which is relatively cheaper compared to that of IAME and ROK engines which are around the 3500-4000 USD range. So, when it comes to karting on a budget, buying a Rotax engine is your best bet.
Cons: Require a lot of maintenance
While Rotax engines are one of the cheapest engines on the market to purchase, the manhours that are required to maintain its condition and performance is far more than other TAG engines. The issue mainly lies with how many components are on the engine. If the battery voltage is low, the engine will misfire. The power valve needs regular cleaning and maintenance to get in the right power band, the switches (to turn on & off) have been known to gives hassles also. While cleaning and repairing parts is common, the rate at which it is done for Rotax engines is much higher, meaning that they require a lot more attention and care. Therefore, if you are a beginner in karting, especially in kart setups, you may be better off with another engine.
Pros: High Top Speed
Another standout quality of the Rotax engine is its overall top speed. On circuits with less tight bends, and more straights, the Rotax engine can perform quickest as the mid to top end range are its strongpoint. This means that in high-speed tracks such as Todd Road or PFI, the Rotax engine is your best bet as tracks that have long straightaways and high-speed corners is where the Rotax excels.
Cons: Struggles on low-speed tracks
On the contrary, tighter racetracks the Rotax engine does not suit, given the torque range the engine performs best in. The Rotax engine doesn’t have the same acceleration as other TAG engines, it takes a while before the driver can step on the throttle after taking a corner. On top of that, the driver must be smooth in applying the throttle, otherwise the engine will bog down. In layman’s terms, when an engine is bogging down, it means that the engine does not have enough revs (RPM’s) and lacks initial acceleration. This is not good, as karting needs the driver to continuously keep the revs high or the engine will lag for a delayed period.
Pros: Robust and Reliable
Another thing that Rotax is known for is its engine rebuild interval! An engine rebuild interval is a recommended number of hours an engine can keep running in peak condition before requiring maintenance and repair. According to Rotax themselves, the ideal engine rebuild interval to ensure reliability is 40 hours, which, compared to IAME and ROK which have an engine rebuild interval of 15-20 hours, does not even come close to the Rotax’s reliability. This can be beneficial for race weekends with multiple heats or ones that are long in length, such as endurance races.
But keep in mind that performance will be optimal in a certain window, then a smaller drop off will occur. It’s always best to be advised by your engine tuner as these are the people you will be guided by at race events.
Cons: Low Torque
Torque is important as it represents how much load an engine can handle to produce a certain amount of power. This is beneficial as it helps the go-kart turn and accelerate quickly out of a corner. The Rotax engine has 9000 rpm according to Rotax’s official website. If we compare this to the IAME which has 10,750 and the ROK with 11,500 rpm, the Rotax is inferior in this category as it does not even crack the ten thousand range. Because of this, it means that the engine cannot handle a massive load. Its low torque is also an explanation as to why the Rotax engine is not known for its acceleration.
So those were some of the pros and cons of the Rotax engine. Remember that these points given are subjective and not set in stone. These pros and cons were formed according to the experiences of other drivers using the Rotax engine. At the end of the day, everyone’s experience is different. What others have observed you may not even experience. An engine’s compatibility in relation to the kart and driver is always down to feel. Therefore, understanding your go-kart and being able to relay the information on how the go-kart feels is important.
Still to this day, Rotax has formed one of the most highly sought-after race events where drivers can’t just simply enter. They need to qualify for the Rotax Grand Finals through limited tickets in their chosen country to race in identical karts and engines. This has been around for over 20 years now, travelling to all parts of the globe.