THE BIKINI PROJECT

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Honda CB500 Four 1972 - Blacksquare Motorcycles

ENGINE, FUEL SYSTEM, IGNITION & EXHAUST

ENGINE: 1976 HONDA CB550.  Bead-blasted, completely rebuilt from the bottom up, bored +0.5 mm to 59 mm (the original cylinder bore is 58.5 mm) and fitted with WISECO pistons (kit model number 40059M05900).  Compression increased to 10:1 from the original 9:1 and displacement increased from the original 544 cc to 553 cc. Cylinder boring and valve job by TSI Competition Engines.

CARBURETORS: original KEIHIN, model 087A, completely rebuilt.

VELOCITY STACKS: one-off custom design, by STEEL DRAGON PERFORMANCE.

TANK: asymmetric, one-off, in-house design, all aluminum, custom-built and polished by BCR DESIGN, capacity = 2.0 US gallons

PETCOCK: by PINGEL, 6000 series

EXHAUST: modified original headers, ceramic-coated with CERAKOTE High Temperature Glacier Series coat.  (When polished, the appearance is that of polished aluminum.)

IGNITION COILS: Dynatek Dyna Coils 5-ohm Dual Output DC8-1; Black DW-200 Wires

POINTS: new, original HONDA

FRAME & SUSPENSION

FRAME: 1972 HONDA CB500, modified tail section, all original welds ground smooth.  Powder-coated in sky blue and then clear-coated by TRICKED OUT CYCLES.

FRONT SUSPENSION: original HONDA, rebuild with new tubes and springs.

REAR SUSPENSION: custom-built by WORKS PERFORMANCE gas shocks, 13.5″-long, Dual-Rate Springs.  (The question about correcting the length of the kickstand when custom suspension is installed comes up a lot, so, in anticipation that it would come up here again, the answer is yes.  The kickstand was lengthened by 1″. It was then polished and chromed.)

WHEELS, TIRES & BRAKES

RIMS AND SPOKES:  by Buchanan’ Spoke & Rim Inc.  “Sun” rims in polished aluminum, stainless steel spokes.

TIRES: MICHELIN Pilot Activ.  Front 3.25 – 19.  Rear 4.00 – 18.

FRONT BRAKE: dual-disc, drilled rotors, original HONDA calipers, stainless steel lines, banjo fittings and 3-way splitter by GOODRIDGE

REAR BRAKE: original HONDA

CONTROLS & INSTRUMENTS

CLIP-ONS: Vortex, 35 mm, 7-degrees, all aluminum

THROTTLE TUBE: G2 Ergonomics Quick Turn Throttle Tube 50-150D, all aluminum

GRIPS: by ARIETE, model 02631-ALL, Alu-Rub Grips (polished in-house)

HAND CONTROLS: by Eurocomponents, model: De Luxe Retro, all aluminum

REARSETS: by JOKER MACHINE, model 09-800S, all aluminum, fully adjustable in all imaginable positions.

3-POSITION REARSET BRACKET: in-house design, allows 3 different positions for the rearsets depending on rider’s size and riding style preference.  CNC-machined from 6061 aluminum. The brackets are approximately 12″ x 5″ x 2″ overall (roughly 300 x 120 x 50 mm). There are two curvatures which offset the mounting points by about 1/2″ (12 mm) and the three circular foot peg positions are themselves some 3/4″ (20 mm thick) allowing the brake pedal and clutch lever to clear the exhaust pipes.  It took a big chunk of aluminum to CNC-machine these.

CLUTCH AND THROTTLE CABLES: custom-made by BARNETT

TACHOMETER: SMITHS Digital Chronometric CHR-R10; 0-10,000 RPM

ELECTRICAL:

HEADLIGHT: restored antique spot light (the bucket was chromed, the reflector was nickel-plated) fitted with a STANLEY lens.

HEADLIGHT RELAY: common latch relay incorporated in the headlight’s bucket.

TAIL/STOP LIGHT: 30-LED TruFLEX by Custom Dynamics.

BATTERY: 8-cell 240CA Lithium battery by Antigravity

REGULATOR/RECTIFIER: by RICK’S MOTORSPORT ELECTRICS, model # 10-100

HARNESS: custom 3-part harness terminating in aluminum aviation plugs; all bullet-socket connectors by VINTAGE CONNECTIONS

PUSH-ON MOMENTARY MINI SWITCHES for the headlight and starter button.

SEAT, SIDE COVERS & FENDERS:

SIDE COVERS: perforated aluminum, designed and built in-house.

SEAT: designed and built in-house, aluminum pan, 1-inch foam, marine-grade semi-perforated black vinyl.

FENDERS: all aluminum, custom-built and polished by BCR DESIGN

EMBLEM: in-house design, 3M epoxy domed decal on black background with chromed letters, custom-made by CHROMED HOG

OTHER:

All laser cutting by Keith Gayman.

All spacers and other specialty parts were machined by “uberacer” Gene at S&S General Services LLC

All welding by master welder Tim at Classic Cycles

SPECIFICATIONS:

OVERALL LENGTH = 80.5 inches (2,045 mm)

OVERALL WIDTH = 28.5 inches (724 mm)

OVERALL HEIGHT = 39 inches (991 mm)

SEAT HEIGHT = 29.75 inches (756 mm)

FOOT PEG HEIGHT: Position 1 = 12.25 inches (311 mm), Position 2 = 13.00 inches (330 mm), Position 3 = 13.75 inches (349 mm)

DRY WEIGHT = 357 lbs. (162 kg)

NOTE: The listed dry weight of an original 1976 HONDA CB550 is 423 lbs. (192 kg).