How do you remove Rear brake drum from Honda fourtrax ATV?

Depending on the year it could be mounted on the right rear wheel or to the right of the rear axle support. If it is on the wheel, you have to remove the spindle by removing the cotter pin and unscrewing the castle nut, then unscrew the bolts holding the cover to the backing plate, then making sure the brakes are backed all the way off, gently work the drum off using pry bars if necessary. Be careful, the backing plate is aluminum and will break easily. If on the axle, you will have to remove the spindle as above. Then you have to remove the axle nuts that are against the drum cover. If they have never been off, soak them in PB Blaster prior to removal, I have had to use heat on quite a few as well to get them off. Once they are removed, the procedure is the same.