early 85 rear disc question

[daves86vmax]

My brother just picked up an 85 that has a manufacture date of 1/85,the rear disc looks different than the reaar disc on my friends 85 that has a date of 2/85..my brothers disc has the pad surface basically floating and captured by a small plate on each side and the plates are held by rivets.the pad surface of the rotor isn't completely solid and you can actually move ita little..anyone know what I'm talking about?my 86 is not like his either so I'm assuming its something yamaha got away from very early in production.

 

[gamorg02]

can u grab some pics?

 

[sdt354]

Sounds like an after market rotor on your Bro's. Possible EBC floater? Yea, pics would be best for ID.
Steve-o

 

[one2dmax]

Yep, bet it's an EBC floating (or Galfer). If stock it will be the same as the right front rotor.

Sean