Standard inner valve spring lower collar, use
C-AEA654.
These are no longer required when using our
C-AEA526 and
C-AEA527 range of silicone wire springs which are a slight interferance fit and friction damped.
Our springs have been successfully used in road and race for many years.
Originally the bottom inner spring location collars were used with all dual springs to prevent breakage caused by the inner spring wandering at high RPM
but modern day spring technology has overcome that.