Boxer Racer: The Butler & Smith BMW R75/5 F750

Alan Cathcart rides the BMW R75/5 F750 racer, one of two factory-framed racers, at Barber Motorsports Park in Leeds, Ala.

January/February 2014

http://www.motorcycleclassics.com/classic-german-motorcycles/butler-and-smith-bmw-r175-zmcz14jfzbea.aspx

By Alan Cathcart

Alan Cathcart on the Butler & Smith BMW R75/5 F750.


Photo By Phil Hawkins

Butler & Smith BMW R75/7 F750
Claimed power: 68hp @ 9,000rpm (rear wheel)
Engine: 745cc air-cooled OHV horizontally opposed twin, 82mm x 70.6mm bore and stroke, 12.75:1 compression ratio
Weight: 348lb (148kg) with oil, no fuel

Road racing history has lots of fascinating footnotes, and one of these is the story of the very last motorcycles carrying the BMW badge to go racing using a factory-built race chassis. This is the story of a bike created in the U.S. with the help of BMW engineers, the first steps on a trail that would lead to BMW’s domination of the early days of Superbike racing in the mid-1970s with the R90S.

BMW’s participation in Superbike racing was part of a process of overhauling the German company’s staid image by competing face-to-face with its Japanese and Italian rivals on the track. After the Adams family purchased BMW’s U.S. importers, New Jersey-based Butler & Smith, in 1971, they were faced with sluggish sales of the R75/5 boxer twin, introduced to the U.S. in 1969 as BMW’s sportiest bike yet. To fix this, company president Dr. Peter Adams instituted a five-year race program aimed at freshening the image of the BMW brand.
Butler & Smith parts manager Udo Gietl (a part-time racer and former NASA engineer), was given the resources to develop a Formula 750 racer based on the R75/5, as the AMA National Championship was to be run for the first time under F750 rules in 1972. With the help of BMW’s American representative Volker Beer, Gietl obtained four factory-built race chassis identical to those used to construct the three works R75/5-based BMW F750 racers that Helmut Dähne, Dave Potter and Hans-Otto Butenuth rode in the April 1972 Imola 200, with Dähne finishing 13th.