Answer:
Forward Iβm heavy, but backwards Iβm not.
Though blind as well, can lead the blind well.
Within, I clean all that is bad and is old. I make juice thatβs the color of gold. Should I die, a filter machine would you need assembled to replace me and beans I resemble.
You need a key to receive an answer from me. The answer you'll find is straight from your mind. What is it?
The man who invented it doesn't want it. The man who bought it doesn't need it. The man who needs it doesn't know it. What is it?
I have two eyes in the front and a lot of eyes on my tail