Retaining Ring Tool
To remove the EVO belt wheel and spider from the Strida KS3 gear box a 46 mm retaining ring needs to be removed. Because the 46 mm retaining ring is recessed in the Strida EVO belt wheel spider a custom tool is required. I have had this tool custom machined and it works well when combined with a impact wrench. The drive is with a 7/8 socket. I use an electric impact driver like this one.
Without this tool a hammer and punch will remove the recessed 46 mm retaining ring but it may damage the ring and be difficult to reinstall.