Fits all 2V Boxer from /5 up to R100GS/R.
The manifolds have been stretched out from 38mm to 40 mm on both ends.
for R60/7 76-78; R75/6 74-76; R75/7 76-77; R80/7 77-81; R90 S 73-76; R90/6 73-76; R100 RS 76-80;
R100 S 76-80; R100 RT 79-80; R100 T 79; R100/7 76
Fits all Airheads from 1981
For BMW OE piston.