TECH TIP: How to Inspect 2 Stroke Reed Petals for Wear
Inspecting your bike's reed petals periodically is a quick, cost effective, and easy do-it-yourself maintenance project that ensures your engine is receiving the proper air and fuel mixtures required to achieve consistent power delivery and obtain peak horsepower output time-and-time again. When checking your reed petals, look for edge chipping, surface tears, cracking, or a peeling of the surface material. Also, check to see if the reed petals are maintaining their static gap against the reed valve surface. The petals should be seated against the cage with roughly .015-inch air gap between the frontal edge of the petal and surface of the reed cage. The tolerance for air gap varies slightly by manufacturer, and also varies per each model. Always refer to your owner's manual for your bike's specific reed petal specifications.
Inspecting a reed petal on a two-stroke motorcycle engine first involves getting access to the reed cage unit. This will require you to remove the carburetor and the reed cage assembly from the engine. The process is fairly straightforward and can be performed with basic tools. If done correctly, you should be able to finish the job in about an hour. Unbolt the carburetor or throttle body, remove the reed cage from the engine and inspect the entire assembly. If the assembly's petals are pulled away from the cage, cracked or have rough edges, the petals should be replaced.
1. Remove the carburetor or throttle body from the engine.
2. Carefully remove the reed cage assembly.
3. Inspect the reed cage for foreign material between the reed petals and its seat. Also inspect the reed petals for deformation or other surface damage.
4. Remove the reed petals and rinse the reed cage components in clean solvent. If the petals show edge or surface degeneration, replace them with a new set.
5. Re-install the new reed petals and all required components to the Reed Cage assembly. Check the clearance between the reed cage with a feeler gauge and compare the clearance to you're bike's specifications. If the clearance is improper, check to see that the unit is assembled properly.
6. Using new gaskets, replace the reed cage assembly, carburetor or throttle body on the engine and complete all required re-installation procedures.
Note: Used reed petals may appear to be in good condition but fail to give the proper clearance due to material elasticity breakdown and softening. In such cases the reed petals should be replaced.
SELECTING NEW REPLACEMENT REED PETALS
Balancing Performance and Durability
Reed petal life expectancy varies dramatically with your bike's engine and intake design and also varies greatly depending on how hard or how often you ride. Someone who is always on the throttle, allowing the engine to constantly run at peak RPMs can expect less life from their reeds petals. If you race or ride for long hours, then it is a good idea to check your reed petals 3-4 times a season to ensure maximum horsepower.