Toshihiko Suzuki maintains the Lump Proof website
in Japan. Toshihiko concentrates on Classic Racing Lightweight
and Ultra-lightweight machines and his page is a delight.
He wishes to share pictures of larger capacity classic
racing motorcycles with us through the Australian based
Classic Motorcycling Lump Proof Connection!

There are 4 pages of CR750 pics and data. the 1st two feature
a Japanese based CR750 which has appeared at Suzuka. Page 3 has some
pics of CR750s in Australia as well as pics of the historic win for
Honda at Daytona in 1970. Page 4 has a series of pics of a US based CR750.

CR 750 Honda

Honda built the CR750 to race at Daytona in 1970 (ed. Patrick Delli has written to advise:

the CR750 first came out in France of all places for the sept 1969 Bol d'Or 24 hour race which they won. Honda brought over 3 full works bikes with a majority of items made out of magnesium, easily spotted on photos by their blackish appearance, including: forks sliders, calipers, Keihin carbs, rear brakes, crankcases.
As a thank you for the help to win that race, they left one with the importer to race in the 70 season in endurance races and it's still in France to this day in a private collection, minus its original crankcases that didn't survive the racing...)

 The real racing however
was done by legions of Honda riders all over the world who
raced kitted CB750 Fours against the best of the rest.

Honda sold a limited number of CR kits for the Honda CB750 for US$10,000
which made them somewhat exclusive considering CB750s could be bought
for not much more than a grand at the time.
The kit consisted of a race camshaft, stronger valve springs, oversize
inlet valves and smaller exhaust valves, 2 ring 10.5:1 slipper pistons
(standard is 3 ring 9:1), a close ratio gearbox and battery-less ignition fixed
at 35 degrees advance.

Also included were four open megaphones, rear sets, racing seat,
petrol tank, aluminium oil tank, fairing,
twin disks up front and a giant 240mm 2 leading shoe drum brake up back.
Special camchains and primary chains were also supplied but this did
not prevent numerous cam chain failures during races.

The standard frame was used contributing to a quite hefty racing weight
of 385lbs. Using 31mm racing Keihin carbs the CR750 produced a
healthy 90ps at 9,700 rpm making it the most pwerful race bike in its class.

Click below for more on the CR750

1997 Murray Barnard