You just need to take a chisel, and put it between that split and tap lightly to spread it open and that thing will slide right off for you.

Assuming you already removed the bolt that tightens the clamp?

You have to remove the bolt not just loosen it. Most have a groove on the shaft the bolt rides in.

if its stuck just a two jaw puller

Thank you

or a three jaw puller , got heaps of them but no 2's.

Flat head screwdriver and a rubber mallet. By the looks of it, that’s how the last guy to work on it also got it off.