Hello all,

I have just stripped down my crankset (after way too long) and ended up having to drill out one of the crank bolts from the spindle. Consequently I have rather 'upset' the threads in the drive side. So I have bought a new spindle however it looks ever so slightly different to the original.
First, the original part has the number A3134-109L etched on it whereas the replacement has A3006-109L etched on it.
Second the ends on the original have 8 holes drilled into the radial lobes (weight-saving I guess) which the new does not. And finally the original has L & R etched on it, and drive side, non-drive side - whereas the new does not.
Aside from this I am assuming it is a compatible piece but I'm intrigued to know a. what do the numbers refer to (length i know) but what is the difference here that I'm not seeing? Is it just weight saving, materials, or possibly a change of manufacture?

Grateful for any help.

Carl