Shock absorber with adjustable spring load

A device for modifying a shock absorber so that the preload of the shock absorber may be adjusted while the vehicle to which it is attached is in motion, said device comprising:

• a chamber member having a cylindrical inner member having an inside diameter slightly larger than the outside diameter of the shock body and having a cylindrical outer member sealingly attached at the upper end to said inner member and forming a chamber between its inner surface and the outer surface of the inner member and positioned coaxially therewith;
• piston means slidingly positioned in said chamber and dividing said chamber into a fluid tight chamber portion and another open chamber portion, said piston means having a spring seat along its lower surface;
• spring means positioned along its upper end in said another chamber portion and extending downwardly therefrom;
• hydraulic fluid held within said fluid tight chamber portion;
• conduit means attached to said chamber member for conducting hydraulic fluid to and from said chamber member;
• and
• a pump affixed to said conduit means, said pump having a handle which actuates a piston located at one end of a fluid cylinder, said fluid cylinder being affixed both to said conduit means and to a fluid reservoir, the pump having valve means which controls the flow of fluid to and from the chamber member of the shock absorber into said fluid reservoir, thereby altering the preload of the shock absorber.