How to Change the Coolant in a 2002 Suzuki RM85
Shop parts for a 2002 Suzuki RM85 Dirt Bike.The 2002 Suzuki RM85 is a lightweight, high-revving 2-stroke dirt bike built for hard off-road use–keeping its cooling system maintained is critical to long engine life and strong performance. Coolant changes are a key part of your maintenance schedule, especially if you ride in muddy, sandy, or high-temperature environments. This bike uses a liquid-cooled system with aluminum radiators and a straightforward single-cylinder layout.
What You–ll Need
- Fresh motorcycle coolant (premixed or mix with distilled water as directed)
- 8mm socket or wrench
- Drain pan
- Funnel
- Distilled water (for flushing the system)
- Gloves & eye protection
Before You Start
- Work only with a completely cool engine to avoid burns and higher risks from pressurized coolant.
- Securely support your dirt bike on a stand so it–s stable while you work.
- If you removed any dirt or mud after your last ride, ensure the area around the radiators & drain bolt is clean to prevent debris from entering the cooling system.
Step-by-Step Guide to Changing Coolant
- Remove the Skid Plate (if equipped): Use your tools to remove the skid plate for clear access to the water pump, located on the right side of the engine.
- Open the Radiator Cap: Twist off the radiator cap on the left radiator to relieve pressure and aid draining. Be sure the engine is cool before doing this.
- Locate and Remove the Water Pump Drain Bolt: Find the 8mm drain bolt at the bottom of the water pump cover. Position your drain pan beneath and carefully remove the bolt to let coolant flow out completely. Tilt the bike gently side-to-side to clear trapped fluid from sections of the engine and radiators.
- Flush (Highly Recommended): For best results, re-install the drain bolt and pour distilled water into the radiator. Remove the bolt and drain the water. Repeat until the water runs clear. Only use distilled water–tap water can add minerals that may damage the aluminum system over time.
- Reinstall the Drain Bolt: Tighten the drain bolt securely but do not overtighten, as the threads are aluminum and can strip easily.
- Refill with Coolant: Place a funnel in the radiator fill neck and pour in fresh coolant until it reaches the bottom of the filler neck. Leave the radiator cap off for now.
- Remove Air Pockets: To ensure all air is purged, gently rock the bike, squeeze the radiator hoses, and top off coolant again if the level drops.
- Start the Engine Briefly: With the radiator cap still off, start the bike and let it idle for one minute. Watch the coolant level–it may drop as air escapes. Shut off the engine if level drops, and top with more coolant as needed.
- Finish & Check Levels: Once you–re sure air has bled from the system and coolant remains steady at the filler neck, reinstall the radiator cap securely.
- Verify System: After riding and letting the bike cool to room temperature, check the coolant level again and add if necessary. Monitor for leaks around the water pump and radiators after the first ride.
Tips Specific to the 2002 RM85
- The RM85 features small-capacity radiators; do not overfill as expansion during use could force coolant out the overflow tube.
- Inspect your coolant hoses for cracks or swelling during this process–the 2002-2008 model hose kits are still available but can be slow to source due to demand.
- Avoid mixing coolant types (such as silicate-based and silicate-free); stick with one type for the life of the engine. When changing coolant types, flush thoroughly with distilled water.
- Always tighten bolts (especially the drain bolt) to factory specifications to prevent leaks or thread stripping.
Disposal – Be Responsible
Old coolant is toxic and should never be poured on the ground or into drains. Always use a sealable container and take used fluid to a recycling center or auto shop that accepts coolant for proper disposal.
Keep Your RM85 Running Cool
Routine coolant changes are one of the best ways to extend the life of your 2002 Suzuki RM85 and keep it performing at its peak. If you notice persistent overheating, check for clogged radiators, hose leaks, or a failing water pump seal – all of which are easier to address with regular maintenance.
Related Shopping Categories
Shop Radiators for a 2002 Suzuki RM85 Dirt Bike.
Shop Coolant for a 2002 Suzuki RM85 Dirt Bike.
Shop Temperature Sensors for a 2002 Suzuki RM85 Dirt Bike.
Shop Tools for a 2002 Suzuki RM85 Dirt Bike.
Shop Radiator Hoses for a 2002 Suzuki RM85 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.