Help with brakes issue

Hi,
I washed my bike yesterday and now I can't backup. It goes fine forward but something is locking up when I try to backup. I tr4iede adjusting the brakes and If I give it enough plsy to backup thre iw too much slack in the front brakes. I don't undersstand why it rolls forward with no problem but backwards it just won't move. Please help as this is a serious dangerous issue. The bike is an 80 kz440b

You need to take the wheel off and brakes apart and inspect the shoes (I assume drum brakes on your model). Check to make sure that the shoe pad material is completely bonded to the metal surface of the shoe metal. I had a situation where the brakes started making noise. Inspected it visually and didn't see anything wrong with the shoes and plenty of meat. Next time I had them apart I inspected again but this time pulled on the edges on the front and the rear of the shoe pads. Found they would separate from the metal with little trouble. Not the whole pad but the leading front in my case. If yours checks out O.K. then a good inspection should turn something else up. Good luck.