1980 Cruiser 5

[GTs58]

It's funny but I think that the letters on bolt head are very deceiving, at first, I thought SA then VS / VB but maybe it's BA for British Association screw

The VB marking is undoubtedly the bolt makers symbol, and the three marks represent the bolt strength/hardness. The bolts were probably outsourced from that manufacturer. A bolt head that does not have those three markings or more is a standard grade bolt.

 

[koolbikes]

The VB marking is undoubtedly the bolt makers symbol, and the three marks represent the bolt strength/hardness. The bolts were probably outsourced from that manufacturer. A bolt head that does not have those three markings or more is a standard grade bolt.

Looking at Bolt Head markings chart it appears that the small triangle stands for CRS (Cold Rolled Steel) having a close tolerance and the three marking are a Grade 5.
My question is ... what is the tread size of this bolt & nut ... Grade 5 ... 4 3/4" ... 3/8" x 24tpi ?

 

[GTs58]

Looking at Bolt Head markings chart it appears that the small triangle stands for CRS (Cold Rolled Steel) having a close tolerance and the three marking are a Grade 5.
My question is ... what is the tread size of this bolt & nut ... Grade 5 ... 4 3/4" ... 3/8" x 24tpi ?

Schwinn could have specified whatever threading they wanted. Didn't Willworkforparts show a 24 tpi?