1982 R65LS Front Brake Rotor Dilemma

[Rodeogeo]

I picked up an R65LS a month ago that has a warped front rotor or two. The previous owner bought it from someone that had let it sit for years and was trying to get it up and running. The previous owner replaced the front brake calipers with new ATE calipers. I'm guessing the old calipers were hanging up and heated the rotors which caused them to warp.
The dilemma is I'm trying not to spend the $370 for each rotor that I can see on several BMW sites parts fiches.
I did some research and EBC rotors seem to be a popular choice. I went to their site and they recommended Perfect Brakes Inc. to get my rotors in the states. That site listed MD606RS and MD606LS for a R65LS. Those rotors have the correct width and bolt spacing but they are 1.935" (49.1mm) deep and the BMW rotors I pulled off are 1.485" (37.7mm) wide. The rotors hit the forks...
I contacted Perfect brakes and did some research on the EBC UK catalog. EBC lists MD606 for the Brembo caliper R65LS and MD605 for the R65LS (doesn't list caliper type). Perfect Brakes sent me the MD605 rotors and they are too wide, a bit too shallow and have four bolts to the wheel instead of five. Perfect Brakes has been great to deal with but I want to get this bike running!
Does anybody know the correct EBC front rotor parts number?
Do I have a Frankenbike? I doubt that since the original rotors do fit (its stamped BMW, AlSi10Cu2, 1231343, 3.11 on the center piece).
Should I have just bought the factory rotors?
Thanks!
Jay

[Justin B.]

Can you transfer the new "disc" to your old "hat?"  As an aside, my '82 LS had Brembos...

[Bob_Roller]

The LS bikes have, or should have the composite wheels, which are wider at the hub than the snowflake wheel, so the depth of the disc carrier is not as deep as the rotors for the snowflake wheel .

I went through this about 10 years ago .

Got the wrong discs the first time .

Can't find the receipt for the discs right now .

You could opt for a rebuild of the rotors, to semi floating type .

https://spieglerusa.com/brakes/brake-rotors/bmw-conversion-old-models.html

https://spieglerusa.com/brakes/brake-rotors/bmw-conversion-old-models/year/1981.html


If you have the OEM rubber brake lines, time to replace them as well .

[Rodeogeo]

Brake lines are all new. The EBC rotor mounts to the hat much differently than the BMW rotor.
I do have the "snowflake" wheels.
Here's a picture of the original rotor and the first one EBC sent me:

[Rodeogeo]

The Spiegler conversion looks nice but it's getting close to the new rotors from BMW (which might not be the right ones either).... But it'd certainly fit!
Thanks for all the help!

[marcmax]

To the best of my knowledge all R65LS's came with dual discs using Brembo calipers. 1981 R65's had an option of dual disks with ATE calipers. According to the Max BMW parts fiche the rotors have different part numbers pn 34 11 236 566 for the ATE caliper dual disk and pn 34 11 236 005 for the Brembo dual disk. Don't know if that is the source of the width issues you are having but I do know that the rotors that fit a snowflake wheel are considerably shallower that the rotors that fit a R65LS "Y" spoke wheel and are not interchangeable.

[marcmax]

Just rereading your initial post I noticed the four bolt rotor mention. They are for post 1984 wheels and would fit a mono shock R65 which uses a different frame/fork combination that the dual shock models. Wheels are more closely sized to the K series bikes.

[wilcom]

Send us  a picture of that front end. I want to eyeball the ATE equipped, Snowflake wheeled 82 LS........ your serial number too so we can see how your bike started it's life.......

[Oconner]

Very early production LS' had  dual ATE calipers. Mine does. They later switched to the brembos

[SoloLobo]

I have two NOS set of Galfer "Green" pads for your ATE calipers if you are in need... they don't fit my LS equipped with Brembo calipers and I would let them go for a song

[Rodeogeo]

I'll send a picture of the bike, wheels and also post the serial number when I get home. I have put several miles on the bike before I pulled the rotors so I know the ATE calipers and the rotors "work". Thanks for the replies!

[Rodeogeo]

Just looked up snowflake wheels on the internet and I might not have them after all...

[Bob_Roller]

Here's a few pictures of composite and snowflake wheels and the difference between the rotors .

First LS composite wheel .

Spiegler conversion rotor .

Brembo caliper .

[Bob_Roller]

Picture of the rotor on a composite wheel .

[Bob_Roller]

Snowflake wheel .

ATE calpier .