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Go-Kart Engine Oil Types – The Complete Guide

Engine oil is an important element of karting that is often overlooked. While many drivers don’t know how to correctly measure their engine oil, others are just not aware of the different types of engine oils available for go-karts.

2-stroke racing oils are the important type of engine oils that you should be looking at for your go-kart. You should mix your oils based on the ratios recommended on the bottle, and these can vary depending on the specific oil you are using.

We are going to take a detailed look at the different racing oils you can use in your kart below. In addition, we’ll be going through a step-by-step process in how to mix your engine oil perfectly, in order to get the best performance and longevity out of your kart.

Why Do You Need To Use Engine Oil?

Most go-karts have 2 stroke engines. These engines require you to mix the fuel with a 2-stroke oil in order for the engine to run properly. This is because 2-stroke engines do not have a built-in oil reservoir, unlike road cars or even 4-stroke engines.

Preserving The Engine

Mixing the oil in with the fuel ensures that the engine still gets the needed lubrication while it’s running. This prevents the engine from becoming damaged or wearing out too fast. Thus, engine oil is an essential component when it comes to your kart engine.

Engine Oil Quality

It’s always important to check the quality of the engine oil that you are using. Cheap rip off oils can actually do more harm than good when it comes to 2-stroke engines. You need to make sure that you are buying oil from a well-known brand.

Don’t Use Cheap Oils

Cheap oils can damage your kart engine, which is even more expensive to replace or fix than buying proper oil in the first place. Always make sure you read the instructions, and check if it is suitable for use with 2-stroke engines (more specifically with go-karts).

The 3 Main Engine Oil Types For Karting

1. Rotax – Fully Synthetic

Rotax karts tend to run a lot better on fully synthetic oil. Synthetic oil helps with the jetting in a Rotax engine, especially in the higher RPM range. Rotax recommend running 20 milliliters of fuel with this mix, which is extremely lean for a 2-stroke engine. However, you can run it a little bit richer at 30milliliters or slightly more if you are worried about damaging the engine.

2. IAME, X30 (Engines Over 14,000 RPM) – Castor Oils

Castor oils are recommended for the higher RPM engines because the piston ring is exposed to huge amounts of energy. This is because these engines (the style of pistons specifically) are designed and built differently to the Rotax and KZ engines.

The problem is that in these engines the carbon deposits (from dirtier oils) build up over time on the piston and the piston ring. The piston ring will then become stuck and there will be no compression. If you have this issue, switch to cleaner oils such as the Castor 927.

3. Vortex Mini Rok – Motul Or Castor 927

Maxima 927 Castor oil is highly recommended for the Vortex Mini Rok engine. It’s a very clean oil and burns well over high RPMs. The recommended ratio is 35 milliliters on this one.

The other good option for the Vortex Mini Rok (and also the Rotax engines) is the Motul Grand Prix 2T Fully Synthetic oil. The great thing about this oil is that it has a red dye which allows you to clearly see if your fuel has been mixed or not.

Oil Ratios

Of course, the quick and easy way is to premix your fuel straight into a fuel container (whether you use a jerry can or a tank). This is much faster, but it’s also a lot less accurate. If you are aiming to get the maximum performance out of your kart this is the wrong way to do it.

Small Changes Matter

Think about how sensitive these machines are to even the slightest change such as a bolt being loose, or a spacer being removed from the wheel hub. The engine is just as sensitive in its operation. The slightest change in the fuel and oil ratio will have an effect on your kart’s engine performance.

The other problem with premix fuel is that it’s not always used up completely. Mixed fuel that sits for a while is usually not as good as fresh fuel.

Mixing Your Fuel

The best way to mix your fuel and oil is to use a fuel container (marked with liters) and a measuring beaker (marked with milliliters). Most oils will recommend a specific percentage that you need to mix to. However, you can play around with this and find a fuel mix that works for you.

Add your clean fuel to the liter fuel container. Fill the container with as much fuel as you would need, for example 3 liters. You then add your oil to the measuring beaker according to the number of milliliters you are mixing your ratio to.

So, if your ratio is 25% (25 milliliters of oil to 1 liter of fuel), then you would calculate the amount of oil you need according to the amount of fuel you have. So, if we are doing 3 liters of fuel, you would calculate the amount of oil you need by: 25 x 3 = 75 (25 milliliters of oil x 3 liters of fuel = 75 milliliters of oil to add to the fuel mix).

Use Fresh Fuel

Always use fresh fuel on race day to get the best performance out of your kart and mix your fuel on race day. Oils do not necessarily go off, but there are chemicals in the oils which can lose their strength and potency over time, and this can cost you small but measurable amounts of performance during the race.

Final Thoughts

Engine oils are very important in 2-stroke engines. Mixing the fuel is an easy process, however most people are too lazy to do it properly. If you want to get the best performance and the longest durability out of your engine, it’s important to mix your fuel with the right oils, and the correct ratios.