Hi everybody. First post here. I just picked up an old cruiser bike, a Zenital, dating from the early 80's. It was 10 dollars and I thought it might be good for a rat rod buildup, especially since it has pretty good chainstay width. I have not been able to find out much about this bike, or even Zenital in general. It's a 5 speed with pretty crappy components: Sunrace freewheel and rear derailleur, polygon side pull brakes, and steel rims. First of all, does anyone know anything about these bikes? And secondly what size bottom bracket can i get as a replacement for the junk that is there now (I want to swap for a vintage biopace double or triple chainring setup, so square taper BB is my preference). Thanks!