03-16-2014, 01:24 AM
The fork seal is one serious seal. Its not an oring it's like 3/8 inch thick, because it is under tremendous pressure. The fork tube is sealed top and bottom. It has a spring a damper rod full of holes and oil in it. When a 540 pound motorcycle with a 180 pound rider ( example only) hits a bump or the front brakes are applied, the front end collapses, closing the distance in the coil binding in the spring, and air pressure forces the oil thru the holes in the damper rod at tremendous force. If there is a leak, the oil will be forced through that spot with extremely high pressure, which is why your buddies say you will visually know if your fork seal is leaking. It's like air leaking out of a tiny hole in a balloon. There is nothing gentle about it.