How to Change the Oil in a 2025 GAS GAS EX 300: A Comprehensive MotoSport.com Guide
Shop parts for a 2025 GAS GAS EX 300 Dirt Bike.
Keeping your 2025 GAS GAS EX 300 running smoothly demands regular maintenance, and one of the most important routine tasks is changing the transmission oil. While two-stroke dirt bikes like the EX 300 require less frequent oil service compared to four-strokes, fresh oil is critical for long component life and optimal shifting performance. Here's how you can change the oil efficiently and safely, tailored specifically for your 2025 GAS GAS EX 300.
Tools and Supplies You Will Need
- 6mm Allen socket or T-handle (for drain plug)
- Oil drain pan
- Funnel (long-neck/flexible works best)
- Clean rags/paper towels
- New transmission oil (Capacity: 900ml for the 2025 EX 300)
- Torque wrench (recommended)
- NICECNC Oil Drain Tool Kit (optional but highly recommended for mess-free changes on GAS GAS EX models)
- Nitrile gloves (optional, but helps keep hands clean)
2025 GAS GAS EX 300 Specific Call-Outs
- The 2025 EX 300's engine case holds 900ml of oil; avoid overfilling and use a graduated measuring cup or the correct bottle markings to ensure accuracy.
- The fill plug is on the side of the engine and can be awkward to reach, so a flexible funnel or hose is helpful.
- The drain plug is located at the bottom of the case. The factory skid plate has an access hole; no need to remove the plate.
- There is no replaceable oil filter on 2025 two-stroke EX 300 models (unlike four-strokes), but there may be a mesh screen to inspect and clean.
- Use the NICECNC Oil Drain Tool for a cleaner oil change process; it helps direct flow and avoids making a mess on your skid plate or the ground.
Step-by-Step Oil Change Instructions
-
Warm up the Engine
Start the bike and let it idle for 2-3 minutes to thin the oil and suspend debris – this ensures more complete drainage. Stop the engine and allow it to cool just enough so you don't burn yourself. -
Place the Bike Upright
Use a stand to keep the EX 300 vertical; an even stance ensures all old oil drains out. -
Remove the Oil Fill Plug
Locate the oil fill cap on the side of the engine. Remove it to allow the system to vent as the oil drains. -
Position the Drain Pan
Locate the oil drain bolt underneath the engine, centered at the lowest point. Position your oil pan directly below. If using the NICECNC oil drain tool, fit the hose to the drain bolt and direct the hose into your oil pan. -
Remove the Drain Bolt
Using a 6mm Allen socket, carefully loosen and remove the drain bolt. Let the oil flow out. Allow several minutes for all oil to drain, gently rocking the bike side to side to facilitate complete emptying. -
Inspect and Clean the Drain Bolt
Wipe the drain plug clean. If equipped, check the magnet for the presence of metal particles (a normal sign of wear, but in excess can indicate issues). Replace the sealing washer if damaged. -
Check and Clean the Mesh Strainer (if present)
Some EX 300s have a small reusable mesh strainer in the drain location. Carefully remove it, clean it with brake cleaner or fresh oil, and reinstall. -
Reinstall the Drain Bolt
Thread the drain bolt (and strainer if used) back in by hand to avoid crossing the threads. Torque it to manufacturer spec (typically around 10-15 Nm for most enduro bikes, but check your service manual). -
Add Fresh Oil
Insert a funnel into the fill port. Pour in 900 ml of the recommended transmission oil. Pour in two stages (first 500 ml, then 400 ml) for better control and to avoid overfilling. If unsure, check level via the sight glass, dipstick, or fill hole markings. -
Reinstall the Fill Cap
Wipe any spilled oil, then screw the cap back on snugly. -
Check for Leaks
Start the engine and let it idle briefly. Inspect the drain plug and fill cap areas for leaks. If leaks are present, re-tighten as necessary. -
Dispose of Old Oil Responsibly
Pour used oil into a designated container for recycling at your local MotoSport.com service center or authorized oil recycling facility.
Expert Tips: Getting the Best from Your 2025 GAS GAS EX 300 Oil Change
- Check the condition of removed oil for signs of excessive wear or contamination—a foamy or milky appearance could indicate water intrusion.
- Replace the drain bolt's washer or O-ring each oil change if you notice flattening, cracks, or ongoing leaks.
- Changing the oil at the recommended intervals—after every several rides or every 10-15 hours of use—will maximize performance and long-term reliability.
- Always use manufacturer-recommended oil viscosity and specification for your EX 300.
Model-Year Call-Outs for the 2025 GAS GAS EX 300
- The NICECNC Engine Oil Drain Tool is compatible with all 2021-2025 GAS GAS EX 125-300 engines, allowing for a cleaner and efficient oil change. You do not need to remove the skid plate, which saves time and reduces mess.
- As a two-stroke, the EX 300 shares its design with KTM and Husqvarna siblings, so many tools and tips cross over between these brands, but always verify using your GAS GAS manual.
Changing the oil in your 2025 GAS GAS EX 300 is straightforward and a good opportunity to inspect components for wear or damage. Careful attention to detail, regular maintenance, and quality fluids from MotoSport.com help ensure your bike remains race-ready and reliable every ride.
Related Shopping Categories
Shop Motor Oil for a 2025 GAS GAS EX 300 Dirt Bike.
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Shop Oil Drain Pans for a 2025 GAS GAS EX 300 Dirt Bike.
Shop Tools for a 2025 GAS GAS EX 300 Dirt Bike.
Shop Oil Fillers and Drain Plugs for a 2025 GAS GAS EX 300 Dirt Bike.
Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.