Front shocks making a clicking sound?

Hey guys, I took my 87 TRX 350 out for some trail riding today and noticed that after riding for a little while that one of/maybe both of my front shocks were making a clicking sound at times when I would hit a bump or dip on the road….any ideas on what could cause that?

I just recently restored this bike and cleaned up and oiled both of the shocks prior to riding today and they worked just fine with no issues at all. It seems that after the bike had been running for a while and gotten warm is when it started. They are both non-adjustable stock spring air shocks just fyi.