How fast does the motor in my Shredder Joe SDJ616 spin? Your Shredder Joe SDJ616 has a 13-amp motor that spins at a rate of 8,000 RPM. Related articles What is the mulching capacity of my Shredder Joe SDJ616? What size trimmer line does my Shredder Joe SDJ616 use? What material are the individual nozzles made of? vWhat is the ideal use for the 24V-JB-LTE? Are there any surfaces I shouldn't use the Cleaning Gel on?