Reed spacer?

They are used to move the power within the RPM range. I forget which way is which but installing a spacer between the carb and cage moves the power up or down in the RPM range and installing it between the cage and cylinder moves the power the other way.
 
iv got one and if you put it between the motor and reed cage powerband hits at lowe between carb boot and reed cage powerband hits at higher rpm
 
not really. they do help with some aftermarket carbs because they space the carb back so it doesn't hit the clutch actuator. only reason i would ever run one. just an extra gasket to leak in my book
 
If you mount the Reed spacer Straight to the intake Side With the reeds Behind the spacer it Moves power to Low-mid throttle Response , If you Mount The Spacer Behind the reeds It will Move the Power To Mid-High Throttle ! , I have My 1/2" Spacer Right on the Intake side for Low-Mid !