For anyone facing this problem in the future, as edscoble explained you need to knock out the old cups which are inside the headtube and replace with a cartridge bearing, my replacement bearings were crane creek 41/6.5mm/36degree/45degree, so didn't need to replace the whole headset...cheers
I’m facing this right now, however my issue is now sourcing the crown race as I want to switch forks. How do I know what to use? Do I have to consider stack height for the crown race? Can I use spacers?
For anyone facing this problem in the future, as edscoble explained you need to knock out the old cups which are inside the headtube and replace with a cartridge bearing, my replacement bearings were crane creek 41/6.5mm/36degree/45degree, so didn't need to replace the whole headset...cheers