Trying to replace the rotors on my 86 AW11 SC.
 
I noticed that the RDA replacement for the rears (RDA751) is 258mm x 10mm, while everything else seems to have the rear rotor size listed as 263mm x 10mm.
 
What's with the 5mm difference? I assume lots of people have replaced with RDA's without issue?

Bump

Maybe the theory is that the disc wont develop a lip as it wears. The lip would complicate pad changing in a competition situation. Did you find any other online feedback?

I remember there being a slight difference in size between the mk1a (84-8/86) and mk1b (9/86-89).

That said i remember the difference being bigger than that for one, and the fact that the front rotors on the mk1b is 258mm makes me think its a missprint.

Yeah, possibly a misprint. Just seems strange that pretty much everyone selling them has it listed as 258mm.
 
I emailed RDA, so we'll see if I get any reply.

Rears are RDA751. I have a set of RDA751D's on mine (dimpled and slotted), they're the correct ones.
 
Just remember to give the hats a spray of high temp paint before you install them, as they are prone to surface rust.

there are 2 different sizes. RDA/DBA do not supply the later/bigger rear rotor