The cast stamped number on the Front Brake Rotors of our 94 Accord says Min 19 mm. But Helms lists 21 mm as the minimum disc thickness. The actual measurements I took were: 20.54 20.75, and 20.90, depending upon how I held the mic. The slightest movement had the numbers jumping all over the place.

So, I cannot say for sure what the real spec is, but it is well over the 19 mm casting number. Btw, I noticed that in the Haynes manual their rotor also has the 19mm casting number.

The Rotors are otherwise ok in flatness, surface smoothness, and runout is all ok. So, can I use the 19 mm for inspecton?

 

21mm is the 'resurface' limit,in the Helms service manual, while 19mm is the true min thickness limit.
You can run them thru another set of brake pads for sure.
But get ready to replace the rotors next time around.

 

Fan F_____gtastic. I was hoping that was the deal.