Many thanks for this game my 360k floppy disk is dead...
This was my 1st crack on PC and after 25 years I made it again...
To bypass the drive A: check find these bytes in KARATEKA.EXE:
74 06 E8 82 01
and replace with:
90 90 E8 82 01
To do it, use any Hex editor. I have used Ztree -
www.ztree.com