Need betterbrakes on your old BMW Airhead project? These adapter kits will allow you to run a radial 4 piston caliper and a much larger brake disc.
 
1974-1980 R75 R80 R90 R100:
 Some modification of the fork leg is required with this design.  
Sold as a Hub adapter & caliper adapter for one side only.
 Brake calipers, rotors & brake hoses are not included with this set.
Brake hoses will require a 10mm banjo fitting at the caliper end, so the metal pipe can nolonger be used.
As a single brake this system works well with the original 13-15mm master cylinder. Dual set up a 17mm should be used or an upgrade to an 18 or 19 mm handlebar mounted. 
Brembo radial piston calipers provide the best clearance for spoke wheels. But will require an 18 to 19mm Master Cylinder for dual use.
This design is for use with European 4 piston calipers with 100mm bolt spacing. 
Machined from 6061 aluminum
Caliper mount and disc mount only
 
CALIPER CHOICES:
BMW S1000RR 2009 -18, BMW R1200 1250 S1000XR 2001-202(OEM Part no. 34 11 7 714 783 Left and 34 11 7 714 784 right) You can find good used ones on eBay.
 
BRAKE DISC CHOICES:
2002-2007 Ducati 749, 848, 999 rotors  320mm.
Brembo/ Ducati part# 49240751A, 49240551A 
EBC part# MD622X
NG part #1051
 
1981-1984 R80 R100:
Machined from 6061 aluminum
Caliper mount and disc mount only
Stock mastercylinder should work fine.
 
CALIPER CHOICES:
BMW S1000RR 2009 -18, BMW R1200 1250 S1000XR 2001-202(OEM Part no. 34 11 7 714 783 Left and 34 11 7 714 784 right) You can find good used ones on eBay.
 
BRAKE DISC CHOICES:
2002-2007 Ducati 749, 848, 999 rotors  320mm.
Brembo/ Ducati part# 49240751A, 49240551A 
EBC part# MD622X
NG part #1051
 
1981-1987 R80G/S:
1979-1984 R65 R80ST:
1981-1984 R80 R100:
Machined from 6061 aluminum
Caliper mount and disc mount only
Stock mastercylinder should work fine for single disc.
 
CALIPER CHOICES:
BMW S1000RR 2009 -18, BMW R1200 1250 S1000XR 2001-202(OEM Part no. 34 11 7 714 783 Left and 34 11 7 714 784 right) You can find good used ones on eBay.
 
BRAKE DISC CHOICES:
2002-2007 Ducati 749, 848, 999 rotors  320mm.
Brembo/ Ducati part# 49240751A, 49240551A 
EBC part# MD622X
NG part #1051
 
R100GS 4 PISTON RADIAL:
1981-1984 R80 R100:
Machined from 6061 aluminum
Caliper mount and disc mount only
Stock mastercylinder should work fine for single disc.
 
CALIPER CHOICES:
BMW S1000RR 2009 -18, BMW R1200 1250 S1000XR 2001-202(OEM Part no. 34 11 7 714 783 Left and 34 11 7 714 784 right) You can find good used ones on eBay.
 
BRAKE DISC CHOICES:
2002-2007 Ducati 749, 848, 999 rotors  320mm.
Brembo/ Ducati part# 49240751A, 49240551A 
EBC part# MD622X
NG part #1051