How to Refill the 2-Stroke Oil Tank on KTM, Husqvarna, and GasGas (TPI & TBI Models)

Modern fuel-injected two-stroke dirt bikes from KTM, Husqvarna, and GasGas are incredibly advanced machines. Thanks to oil injection systems found on TPI and newer TBI ENDURO models, riders no longer need to premix fuel at the gas station.

Instead, the bike stores two-stroke oil in a separate reservoir and automatically meters the correct amount into the engine while you ride.

But if you’ve ever tried to refill the oil tank, you’ve probably noticed something frustrating:

The filler opening is tiny and awkward to pour into.

In this guide, we’ll explain:

• How to refill the 2-stroke oil tank properly
• How much oil the tank holds
• Common mistakes riders make
• The easiest way to fill the reservoir without spills

---

How the Oil Injection System Works

Modern KTM group two-stroke enduro models use a separate oil tank and electronic oil pump to supply lubrication to the engine.

Instead of mixing oil and gas manually, the system injects oil automatically based on engine load and RPM. This improves fuel efficiency, reduces smoke, and simplifies fuelling.

When the oil level gets low, a warning light appears on the dash, indicating it’s time to refill the oil reservoir.

Manufacturers recommend refilling the oil tank as soon as possible after the warning appears to ensure the engine remains properly lubricated.

---

How Much Oil the KTM 2-Stroke Tank Holds

Most modern KTM, Husqvarna, and GasGas oil-injected two-strokes hold about 0.6–0.8 litres of 2-stroke oil in the reservoir.

Typical capacity examples:

• KTM 250/300 TPI: ~0.7L
• KTM 250/300 TBI: ~0.8L
• KTM 150 XC-W: ~0.7L
• Husqvarna TE / GasGas EC: similar capacities

That amount usually lasts several tanks of fuel depending on how aggressively the bike is ridden.

Step-by-Step: How to Refill the 2-Stroke Oil Tank

If you’re searching for “how to refill KTM TPI oil”, the process is simple but requires a little care.

1. Locate the Oil Tank Cap

On most models, the oil reservoir cap is located near the fuel tank or under the seat area.

2. Open the Oil Tank

Turn the cap counterclockwise and remove it.

3. Slowly Add 2-Stroke Oil

Pour oil into the tank until it reaches the bottom edge of the filler neck.

4. Close the Cap Securely

Once the oil level reaches the correct height, reinstall the cap and tighten it.

5. Check for Spills

Wipe away any oil that may have dripped onto the frame or engine.

---

The Biggest Problem Riders Run Into

Although the process is simple, the design of the oil filler makes it easy to spill oil.

The opening is:

• Deep inside the frame
• Narrow
• Difficult to see inside 
• On newer models, the fill neck is black and very hard to judge oil level

Because of this, riders frequently:

• Spill oil down the frame
• Overfill the reservoir
• Get oil on wiring or the throttle body

One rider even described getting oil “everywhere on the oil pump and engine” after filling the reservoir due to overfilling and poor visibility.

It’s a very common annoyance for owners of TPI and TBI bikes.

---

The Simple Tool That Fixes This Problem

A purpose-built oil funnel makes refilling dramatically easier.

Instead of trying to pour directly into the tiny opening, the funnel attaches securely to the filler neck and gives you a large, easy-to-use opening for the oil bottle.

Benefits include:

• Cleaner oil refills
• No spill on engine
• Easier control when pouring
• Less chance of overfilling

For riders who maintain their bikes regularly, it quickly becomes one of those tools that lives in the garage.

A Funnel Designed for KTM, Husqvarna, and GasGas

If you ride a modern oil-injected two-stroke, a dedicated funnel built for the oil filler opening makes maintenance much easier.

You can see one here:

2-Stroke Oil Funnel for KTM / Husqvarna / GasGas
https://t7components.com/products/2-stroke-oil-funnel-for-ktm-gas-gas-husqvarna

A Simple Tool That Solves the Problem

The easiest solution is using a purpose-built funnel designed specifically for these bikes.

The 2‑stroke Oil Funnel for KTM / Husqvarna / Gas Gas is designed to attach directly to the oil fill opening, allowing you to pour oil smoothly without spills or guesswork.

Instead of trying to balance a bottle over a tiny hole, the funnel gives you a stable, controlled way to refill the tank.

What Makes It Stand Out?

What makes this funnel stand out is the unique push rod design thats been developed by us. The process is simple, you attached the funnel to the filler neck and remove the storage cap and push-rod.

You begin to our oil into the funnel until you see the oil level not dropping, it may look "overfilled" but here is where the magic comes in. Install the push-rod and place storage back back on, now you can remove your funnel and that excess oil will remain sealed in the funnel. No mess, no spills. 

Next, you simple empty the remaining oil back into your two-stroke oil jug to use next time. No waste.

Designed Specifically for Modern Two-Strokes

Unlike generic funnels, this tool is made specifically for oil-injected KTM-group bikes.

Key features include:

• Secure sealing gasket that prevents leaks while filling
• Push-rod plug system allows you to "overfill" in the funnel
• Top and bottom caps to keep the funnel clean between uses
• PETG construction, which is resistant to oils and chemicals
• Wall holder for easy storage

The funnel installs with a simple push-and-twist motion, making it quick to use whether you're in the garage or prepping before a ride.