This adds unnecessary time and expense. You can now use this revolutionary and creative new tool that we have developed, which eliminates this step completely. This patent pending "on bike" valve spring compressor kit for Milwaukee-Eight® engines, works with the cylinder head installed on the engine. Simply remove the rocker box covers and rocker arms, and install this unique compressor on the rocker arm shaft. Once the cylinder is filledwith compressed air, the technician can easily rotate the tool and compress the top collar of the valve spring exposing the keepers to remove the top collar, valve spring, and seal. This patent pending tool dramatically saves time for any technician working on Milwaukee-Eight® performance upgrades or service work.