Does anyone know what the identifying marks are on the 9lbs rotors?

 

there are no stock 9lb 13b rotors. there are 9.5 and 10.5 and 11.5. I think some of the 12a's were 9lb rotors.

UNless you're pretty experienced you can;t just look at a rotor and tell what it is. IF you wanna post some good pics I can help you. A very accurate digital scale is also useful, but dont forget about bearing weight which is not included in rotor weight. Mazdatrix.com has a nice chart with rotor information you might wanna check out.

 

s4's have a cast looking combustion chamber and s5's have a machined surface if that helps out.

 

for a second i thought this was going to be a smartass variant of the "10-pound *****" joke ...

guitarjunkie28 ~ do you have any pics of an S5 rotor (cleaned up, of course). i'm curious to see how machined the stock surface of the recess is ...

 

i don't have any pics, and i don't have any laying around...
it looks like a bunch of lines were carved into it--like a ball mill running over it a bunch of times.

it might be better for you to take a pic of what you've got--then even if i can't tell what it is, maybe someone else can.

 

no ... you misunderstood, i'm sorry ... my fault. i just wanted to see what the S5's look like. i have S4 rotors only, but i was curious about the S5's because of what you said in your previous post. i wanted to see how it looked compared to the preparations i'm making on the 12A that i'm building now. that's all ...

 

okie...my bad