How to Change the Coolant in a 2007 Honda CR85

Shop parts for a 2007 Honda CR85 Dirt Bike.

Changing the coolant in your 2007 Honda CR85 is one of the most important maintenance tasks to keep your dirt bike performing at its best. The CR85's compact, high-revving engine relies on fresh coolant to regulate temperature under the demands of aggressive riding. This guideproprietary to MotoSportwalks you through each step, highlights points unique to the CR85, and ensures you get the job done right.

What You Will Need

  • Fresh coolant designed for aluminum engines
  • Basic hand tools (screwdriver, wrenches)
  • Drain pan
  • Rags
  • Gloves and eye protection

Preparation

  • Make sure the engine is completely cool before starting to prevent burns from hot coolant.
  • Stabilize your CR85 on a stand in a well-ventilated area.
  • Remove the seat and fuel tank to access the radiator cap and coolant hoses (refer to your model's manual for removal stepson the CR85, this involves unbolting the shrouds, fuel tank bolts, and disconnecting the fuel line)–5.

Draining Old Coolant

  • With the fuel tank off, locate the radiator cap and the coolant drain bolt or lower hose on the right side of the engine.
  • Position the drain pan underneath.
  • Remove the radiator cap slowly to release any pressure.
  • Remove the drain bolt or detach the lower radiator hose; allow the coolant to fully drain into the pan.
  • Inspect the drained coolant for signs of oil or debris, which could indicate other issues.

Flushing (Recommended)

  • If the old coolant looked contaminated, flush the system with clean water. Add water, reinstall the cap, run the engine for a few minutes, and drain again.

Filling with Fresh Coolant

  • Ensure the drain bolt or hose is securely reattached.
  • Slowly pour new coolant into the radiator neck until it's full.
  • Tilt the bike left and right a few times to help remove air pockets.
  • Top up as needed and reinstall the radiator cap securely.

Bleeding the Cooling System

  • Start the engine and let it idle. As the engine warms, trapped air will rise to the top of the radiator.
  • Turn off the bike and allow it to cool briefly, then check and top off coolant as necessary.
  • Repeat until the level stabilizes, ensuring no air is present in the system.

Reassembly

  • Reinstall the fuel tank, connect the fuel line, and bolt down the seat and shrouds in their original positions as outlined in the owner manual–5.

Critical Notes for the 2007 CR85 Owner

  • The CR85's small engine capacity makes it sensitive to overheating. Never operate with low coolant; check after every few rides, especially if you notice any power loss or overheating signs.
  • Honda recommends using coolants compatible with aluminum parts, as standard automotive antifreeze can cause long-term corrosion or gumming in small MX bikes.
  • Inspect hoses and radiator fins for damage or leaks during servicethese can affect cooling performance.
  • After refill, always double-check the coolant reservoir level and inspect for leaks with the engine running and warmed up.

Routine coolant changes not only protect your engine but also extend the life of vital gaskets, water pump seals, and the radiator itself. Perform this maintenance at least every season or more often in severe conditions.

Related Shopping Categories

Shop Radiators for a 2007 Honda CR85 Dirt Bike.

Shop Coolant for a 2007 Honda CR85 Dirt Bike.

Shop Temperature Sensors for a 2007 Honda CR85 Dirt Bike.

Shop Tools for a 2007 Honda CR85 Dirt Bike.

Shop Radiator Hoses for a 2007 Honda CR85 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.