Motorcycle Fork Cartridge Oil Lock & Spring Guide Parts

Motorbike front forks aren't just the two outer tubes you see - there's a separate internal cartridge doing the real work. Our closed vs open chamber article explains more - but sliding in the middle of that cartridge, with a reb adjuster assembly on the bottom & damping piston parts up top, is a fork cartridge rod.

That rod needs to be securely locked to the rebound adjustment bolt, free from fluid leaks. These o-ringed lower tube oil lock cases keep lubricants sealed, with stopper lock nuts & snap rings fastening everything together. Plastic fork spring guides keep the coils centred & stop scraping.

The clicker inside the fork leg presses on the inner pushrod, adjusting the oil flow through the piston & shim stack on the end of the hollow shaft - learn how to use them in our damping adjusters article.