Im going to venture a guess its because its more economical to source and sell the 5GH as the 1WD is manufactured in Indonesia along with the bike.Any Idea why they changed it? Hopefully to make it easier to get off and on! I had a **** of a time getting the original 1WD filter off.
Rubber adjustable belt: slipped and failed.
Metal self adjusting band: slipped and failed.
Socket type: slipped and failed.
Self adjusting jaw: slipped and failed.
Nylon belt adjustable: slipped and failed.
I finally busted out my 18" Rigid pipe wrench and the filter didn't stand a chance! It turned right off but I had to remove the left side plastic for clearance.
Turned the new 1WD filter back on with the rubber strap type.
I hope the new 5GH filter is easier. Maybe that was the change?
And yes, the factory installed filter is a ROYAL P.I.T.A to take off. I almost had the front wheel off the ground before mine let go.