Technical specifications
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| Model: |
R 42 |
| Years: |
1926-28 |
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Engine:
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Four stroke, two cylinder horizontally opposed Boxer, pushrod operated, SV
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Capacity:
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494 cc / 30.1 cu in.
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Bore x Stroke:
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68 x 68 mm
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Compression Ratio:
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4.9:1
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Cooling System:
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Air cooled
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Induction:
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1 x BMW Spezial 2 valve, ∅22 mm
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Ignition:
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Bosch magneto ignition
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Starting:
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Kick
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Clutch:
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Single plate saucer spring, dry
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Max Power:
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8.9kW / 12 hp @ 3400 rpm
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Transmission:
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3 Speed
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Final Drive:
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Shaft
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Gear Ratio:
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1st 2.50 / 2nd 1.50 / 3rd 1.07:1
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Frame:
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Twin loop steel tubular frame
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Front Suspension:
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Plate spring, 5 laminae
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Rear Suspension:
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Rigid, Spring loaded saddle
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Front Brakes:
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∅150mm Drum
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Rear Brakes:
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External shoe brake at the gearing on Cardan shaft
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Front Tyre:
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27 x 3.5" low pressure or 26 x 3.0" high pressure
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Rear Tyre:
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27 x 3.5" low pressure or 26 x 3.0" high pressure
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Wet-Weight:
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126 kg / 277 lbs
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Fuel Capacity:
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14 liters / 3.6 US gal
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