No need to weigh the rotors, if they have an N stamped in the combustion chamber along with the F od R, they are the later rotors. Earlier ones only have F/R.

 

Damn... That sucks.

alexdimen, weigh them anyway if you've got a scale handy. It would be nice to doubly-confirm. I was really hoping they were the lighter 83-85 rotors

 

Guys, I tore down a 12A recently that someone had goofed. The rotors were '78-'82 but the coutnerweights were '83-'85. The stationary bearings were quite worn.

vipernicus42, you meant to say '83-'85.

 

This thread has stricken me with a major case of n00bitis.

Jon

 

Will do.

 

I just got done tearing my 12a down too and I have the same problem except I have 83-85 rotors and 81-82 front counter weight and flywheel. My front and rear
stationary gear bearings are worn too. What are these people thinking? Many people just slap **** together and dont' give a damn. From where I come from we call them HACKS! hehe.

 

Well, my scale sucks. I weighed a S5 FC rotor I had and it was 9.25 lbs. Those are supposed to be9.5, so the scale is off. These 1st gen rotors were both a little over 9.6 on the scale. Since the scale reads low, that puts them at a little over 10 lbs... in other words, they are 81-82.

So, still for sale and thanks for the info guys.