How to Change the Oil in a 2015 Yamaha TTR125L: Step-by-Step Guide
Shop parts for a 2015 Yamaha TTR125L Dirt Bike.
Changing the oil in your 2015 Yamaha TTR125L is a straightforward maintenance task that ensures your dirt bike continues to run smoothly. Whether you're a seasoned rider or new to dirt bike maintenance, this robust MotoSport.com guide will take you through all necessary steps, including tools, tips, and model-specific notes to keep your Yamaha in top condition.
Tools and Supplies Needed
- Socket wrench set (including a 17mm socket for the drain bolt)
- Oil catch pan
- Clean rags or shop towels
- New engine oil (use the type and weight recommended in your owner's manual, typically 10W-40 for this model)
- Oil funnel
- New crush washer for the drain bolt (optional but highly recommended)
- Gloves
Preparation
- Warm the engine by letting it idle for a few minutes. This helps suspend any contaminants and allows the oil to drain out more completely.
- Ensure the bike is stable and on its kickstand (the left lean helps with draining), or use a bike stand if preferred. Make sure you are working in a well-ventilated area.
Step-by-Step Instructions
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Locate the Drain Bolt
- The drain bolt is located on the left side of the engine, down low by the foot peg.
- It is easy to find and access on the TTR125L, which is a benefit of this model over others where bolts might be underneath.
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Drain the Old Oil
- Place your oil catch pan directly beneath the drain bolt.
- Carefully use your socket wrench to loosen and remove the drain bolt. Be cautious not to strip the threads–do not over-torque.
- Once the bolt is removed, allow the engine oil to drain fully. Tipping the bike slightly to the left can help encourage every last drop out.
- After draining, it helps to kick the bike over a couple more times (without starting) to circulate any remaining oil for full evacuation.
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Replace Crush Washer and Clean Components
- Inspect and replace the metal crush washer on the drain bolt if it shows signs of damage or wear. These washers are inexpensive and help prevent leaks.
- Thoroughly wipe the drain bolt and the mating surface on the engine with a clean rag.
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Reinstall Drain Bolt
- Hand-thread the drain bolt back in, followed by a snug fit with your wrench. Do not over-tighten–just a firm, snug fit to avoid stripping the threads.
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Add New Oil
- Unscrew the oil filler cap (with attached dipstick) on the top/side of the engine.
- Using a funnel, add the correct amount and type of fresh oil as specified in your owner's manual (for the TTR125L, double check the amount stamped near the filler – it's usually around 1 liter but always verify for your model).
- Wait a minute for the oil to settle, then insert (but do not screw in) the dipstick to check the oil level. Add oil as needed to reach the appropriate mark.
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Check for Leaks & Final Inspection
- Wipe down the engine area to clean any spilled oil.
- Start the engine and let it idle for a few minutes, then shut it off and inspect for leaks around the drain bolt.
- After a few minutes, recheck the oil level with the bike upright–not on the side stand–by removing, wiping, and re-inserting the dipstick, then adjusting the oil level as needed.
Specific Call-Outs for the 2015 Yamaha TTR125L
- Drain Bolt Position: The oil drain bolt is conveniently located on the left side of the bike, making oil changes easier than on models with bottom-placed bolts.
- Crush Washer: It is good practice to replace the crush washer with every oil change to avoid leaks.
- Oil Capacity: The TTR125L often has the recommended oil amount stamped directly on the engine case, so check here if unsure. This model typically takes about 1 liter, but always double-check.
- Checking Final Level: Always check the oil level with the bike upright (not on the kickstand) for an accurate reading, and do not screw in the dipstick while checking.
- Filter Change: The TTR125L does not use a traditional oil filter cartridge; it uses a screen that is often left as-is unless major engine work is being performed.
Common Mistakes to Avoid
- Over-tightening Drain Bolt: The aluminum threads can strip easily. Always use a gentle, snug force.
- Forgetting to Replace the Crush Washer: This can cause leaks.
- Overfilling or Underfilling Oil: Always use the dipstick and add oil slowly to prevent spills or incorrect levels.
- Not Running the Engine After Adding New Oil: Running and then rechecking helps ensure proper oil distribution and an accurate level reading.
Final Tips
- Always dispose of used oil responsibly at your local recycling center or auto parts store.
- Track your oil changes in a maintenance log to keep your bike running at its best.
- For the most accurate instructions for your specific year and variant, refer to the owner's manual in addition to this guide.
Changing your oil regularly is one of the most important—and simple—ways to keep your Yamaha TTR125L performing at its peak for seasons to come. For all parts, oil, and maintenance accessories, trust MotoSport.com for professional-grade gear and support.
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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.