BAck in the 70s I had a late 40s early 50s Schwinn that I bought to deliver papers on. It had a ginormous basket and I would load it with 50-70 lbs of papers I was a good 160 and would ride my brother on the rear rack some times. Those things could take the abuse and just never quit.
Unless its making noise I'm sure all the bearings are fine, A little grease and that thing will outlast us all.