Originally Posted by
fietsbob
Basically to BF level generalizations; aluminum various alloys can be like steel ; ..high strength use less , low cost use more. to be equivalent .. in practical, use,..
Still not sure what you’re trying to say. The S83 is all Al, alloyed in some composition. The S84 has an Al head joined to a steel post. I see no problem with the S84 construction, nor that of the S83.