'82 and '83 rotor differences

[Dave T.]

I assume that the '82's single disc is larger than the dual '83 discs. Am I wrong?

Cecil (canadianlouie) told me about an Ebay auction and I emailed the seller and asked him about fitment. I bid on the rotors, but I don't think they will fit on my '82 model, so I figured I'd just make this guy pay a lot for these rotors I may or may not need ?::)....

Here is the link....
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=10066&item=1874815525

Here is the link for the "left" side rotor...
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=10066&item=1874815505

What do you guys think?

I quit bidding because I don't think they will fit my '82. Looks like they will fit an '83 though. I wonder what the O.D. is?

[Brian Moffet]

Well, I happen to have both a Radian and an 83 Vision in my garage.  The rotor looks to be 10.5 inches outside diameter, and 2 5/8 outside to inside diameter.  This is the same as on my vision.  I didn't measure the thickness of the rotor.

FYI
brian

[Brian Moffet]

Just checked my service manual, 82 had a 11.7 inch brake, 83 had 10.5 inch brake on the front.

Brian

[Dave T.]

So I am right, these rotors will NOT work on my '82. My '82 single rotor is 297mm in diameter, and 5mm wide. Where as the '83 rotor is 10.5" inches in diameter.

Well, anyway, If you guys need a new rotor for you '83 Vision, bid away....

P.S. They retail for $183 each...

Thanks M  ;D

[Lucky]

If you have acess to a machine shop, or are good at fabrication, you could make adapters to move the calipers out.  the mounting for the rotors is the same, plus they are vented.  I think Jason has done this...

"I figured I'd just make this guy pay a lot for these rotors I may or may not need  .... "

Not Nice DT, The natural tendancy here is to help each other out...

[ricep55]

When my 1983 Vision mags were ruined in an accident, Yamaha sent out a pair of 1982 mags and the dealer simply mounted the 1983 dual rotor brakes on the 1982 mages with no problem.

While the mags weren't the right color for the bike (a nag I posted on earlier) the brakes worked fine.

[Cdnlouie]

Has anyone ever mounted two 82 rotors on the front of a Vision?

Since the 82's are bigger (larger disc more surface area) and more robust a twosome of those combined with the right master cylinder although getting the right fork tube and caliper would be the problem.

I suppose one could also leave the larger 82 disc on one side and add an 83 fork leg and caliper on the other.  Now that would be a sight!

But if you were looking to increase braking surface area it would definitely give more than the 82 and the 83 smaller dual brakes, assuming you can get the right amount of master cylinder pressure to use it.

Of course balance in not an issue since running one disc on one side has been pretty common practice for years, so no big deal about one that is a bit smaller.

You can tell from this post that winter is boring here,   ::)

[Rick G]

HI Louie, A fellow in Tracy CA. had a V with a vmax front end on it . It used two '82 rotors that were machined down a bit to fit inside the calapers.