1979 Front Rotor

[79beem]

Hello Bob.

The ATE and Brembo calipers can be used on any R65 .

I was under the impression the mono R65's has 285mm diameter discs and 38mm diameter calipers. I think the same as R80/R100's.

 Whereas the 79 has 260mm discs and 36mm calipers. Will the calipers fit a 79 R65?

If so the search for twin front brakes may be over.

Cheers for any insight.

[Bob_Roller]

I should have said 'twin shock ' R65's, I don't know about the mono shock bikes, not many members here have these bikes, so I have no idea if the rotors and calipers are the same as the twin shock bikes .

[79beem]

If I have read Snowbums Brake article correctly,

 http://bmwmotorcycletech.info/brakes.htm

most Airhead Forks and Brembo calipers have 108mm mounting hole centers. My 79R65 has 108 centers.  

He also states that performing a dual disc conversion does improve braking but at the cost of handling.

Whereas the installation of a single 4 spot caliper from a classic K bike or oilhead offers much improved braking with no handling sacrifice or installation trouble other than milling the mounting surface of the caliper up to 4 mill.  

Happy days.

I wasn't looking forward to dishing out $400+.  

[Olliepup]

My 1986 R65 mono shock, with single front disc brake, has a 285 mm disc with a piston dia. of 48 mm.

With a twin front disc setup, the piston dia. is 38 mm.

The caliper dia. you've mentioned is for the twin disc. setup, not the single. This data is from my owner's manual.
Dave

[79beem]

Thanks Dave,
I'd be interested to find out what the mounting hole centres are on your bike. A 36mm to 48mm increase would surely improve braking power. The more options the merrier.