PISTON
	Material	"Lo-ex" aluminium
	Compression ratio	10 : 1
	Clearance (bottom of skirt)	0•0038—0•0039"	(0•096—0•099 mm.)
	Clearance (top of skirt)	0•0077—0•0078"	(0•195—0•198 mm.)
	(both measured on major axis)
PISTON RINGS
	Material	Cast-Iron
	Width	0•097—0•102"	(2•463—2•590 mm.)
	Depth	0•0615—0•0625"	(1•562—1•587 mm.)
	Clearance in groove	0•0025"	(0•0635 mm.)
	Fitted gap (maximum)	•013"	(•3302 mm.)
	Fitted gap (minimum)	•009"	(•2286 mm.)
CYLINDER BARREL
	Material	Close-grained cylinder iron
	Bore size (standard)	61•5 mm.
	Stroke	58 mm.
	Oversizes	•020" & •040"	(•508 mm. & 1•016 mm.)
	Inlet port size	1"	(25•4 mm.)
	Exhaust port size	1Ό"	(32 mm.)
IGNITION TIMING (Fixed)
	Crankshaft (before top dead centre)	16•5Ί
	Piston (before top dead centre)	0•060"	(1•524 mm.)
CARBURETTER (Concentric)
	Type	Amal R626/12
	Main jet	160
	Pilot jet	25
	Needle jet size	•105"	(2•667 mm.)
	Needle position	3
	Throttle valve	3
	Nominal choke size	26 mm.
	Throttle slide return spring (free length)	3-1/16"	(78 mm.)

BEARING DIMENSIONS
	Crankshaft bearing (left- and right-hand)	•75 Χ 1•875 Χ •5625"
		(19•05 Χ 47•625 Χ 14•2875 mm.)
	Crankshaft bearing outer (right-hand)	17 Χ 40 Χ 12 mm.
	Layshaft bush, left- and right-hand (bore)	•6105—•6115"	(15•507—15•532 mm.)
	Gearbox sleeve pinion bearing	•875 Χ 1•875 Χ •375"
		(22•225 Χ 47•625 Χ 9•525 mm.)
	Mainshaft final drive gear bush (bore)	•4965—•4975"	(12•611—12•636 mm.)
	Mainshaft diameter (gear-side)	•6247—•6250"	(15•867—15•944 mm.)
	Mainshaft diameter (drive-side)	•498—•499"	(12•649—12•675 mm.)
	Layshaft diameter (left- and right-hand)	•6095—•6100"	(15•481—15•608 mm.)
	Gearbox mainshaft bearing	•625 Χ 1•5625 Χ •4735"
		(15•875 Χ 39•6875 Χ 11•1125 mm.)
	Big-end roller (18)	4 Χ 8 mm.
	Small-end bearing	•5625 Χ •75 Χ •625"
		(14•2875 Χ 19•05 Χ 15•875 mm.)
	Gudgeon pin diameter	•5617—•5620"	(14•267—14•275 mm.)
TRANSMISSION
CLUTCH
	Type	Multi-plate
	Number of plates	7
	Driving (bonded segments)	4
	Driven (plain)	3
	Overall thickness of driving plates and segments	"	(3 mm.)
	Clutch springs	6
	Free length of springs	1-9/64"	(29 mm.)
	Clutch push rod, short (length)	1•998—2•002"	(50•75—50•85 mm.)
	Clutch push rod, short (diameter)	•186—•188"	(4•7244—4•7752 mm.)
	Clutch push rod, long (length)	5•778—5•782"	(146•76—146•86 mm.)
	Clutch push rod, long (diameter)	•180—•182"	(4•57—4•62 mm.)
SPROCKETS
	Engine	17 teeth
	Clutch	38 teeth
	Gearbox	16 teeth
	Rear wheel	47 teeth
CHAIN SIZE
		0•500 Χ 0•205 Χ 120 links

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D14/4	GENERAL DATA	GD5

GEAR RATIOS
	Gearbox—(top)	1•0                 :1
	—(third)	1•301             :1
	—(second)	1•831             :1
	—(first)	2•843             :1
	Overall  —(top)	6•57               :1
	—(third)	8•55               :1
	—(second)	12•03             :1
	—(first)	18•68             :1
FRAME AND FITTINGS
FRONT FORKS
	Type	Coil spring, hydraulically-damped
	Springs:
	(free length)	17Ό"	(43.8 cm.)
	(spring rate)	35 lb./in.
	(number of coils)	82
	Shaft diameter (top)	1•045—1•046"	(26•543—26•568 mm.)
	Shaft diameter (base)	1•000—1•001"	(25•4—25•425 mm.)
	Sliding tube bore	1•125—1•129"	(28•575—28•677 mm.)
	Upper bush (outer diameter)	1•121—1•122"	(28•473—28•499 mm.)
	Upper bush (bore)	1•058—1•059"	(26•873—26•899 mm.)
	Working clearance	0•013"	(0•330 mm.)
	Lower bush (outer diameter)	1•118—1•119"	(28•397—28•425 mm.)
	Lower bush (bore)	1•000—1•001"	(25•4—25•425 mm.)
	Working clearance	0•006—0•011"	(0•152—0•279 mm.)
	Length (upper and lower)	1"	(25•4 mm.)
REAR DAMPERS
	Type	Coil spring, hydraulically-damped
	Springs:
	(fitted length)	5•7"	(144•78 mm.)
	(spring rate)	100 lb./in.
	(colour identification)	Yellow/tan
SWINGING ARM
	Bush material	Phosphor-bronze
	Bush (outside diameter)	•993—•994"	(25•22—25•24 mm.)
	Bush (bore)	•860—•865"	(21•84—21•97 mm.)
	Housing diameter	•990—•991"	(25•14—25•17 mm.)
	Interference fit on spindle	•0085—•014"	(•215—•355 mm.)
	Spindle diameter	•8735—•8740"	(22•187—22•200 mm.)

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D14/4	GENERAL DATA	GD6

WHEELS, BRAKES AND TYRES
WHEELS
	Rim size and type (front and rear)	WM1-18
	Spoke sizes:
	(front, left-hand)	12 s.w.g. Χ 8-1/16"	(2•641 Χ 204•78 mm.)
	(front, right-hand, inner)	12 s.w.g. Χ 6½"	(2•641 Χ 165•1 mm.)
	(front, right-hand, outer)	12 s.w.g. Χ 6-9/16"	(2•641 Χ 166•69 mm.)
	(rear, right-hand)	10 s.w.g. Χ 7-5/16"	(3•251 Χ 201•612 mm.)
	(rear, left-hand, inner)	10 s.w.g. Χ 6½"	(3•251 Χ 165•1 mm.)
	(rear, left-hand, outer)	10 s.w.g. Χ 6½"	(3•251 Χ 165•1 mm.)
WHEEL BEARINGS
	Front:
	(left-hand)	15 Χ 35 Χ 11 mm.
	(right-hand)	17 Χ 40 Χ 12 mm.
	Spindle diameter (at ground portions):
	(right-hand)	•6687—•6692"	(16•985—16•998 mm.)
	(left-hand)	•5899—•5904"	(14•9835—14•9962 mm.)
	Rear:
	(left- and right-hand)	17 Χ 40 Χ 12 mm.
	Spindle diameter (at ground portions):	•6687—•6692"	(16•985—16•998 mm.)
BRAKES
	Front and rear (diameter)	5½"	(139•7 mm.)
	Front and rear (width)	1"	(25•4 mm.)
	Lining thickness	5/32"	(•4 mm.)
	Total lining area (front and rear)	20 sq. in.	(129 sq. cm.)
TYRES
	Size (front and rear)	3•00 Χ 18"
	Pressure (front)	17 p.s.i.	(1•2 atm)
	Pressure (rear)	22 p.s.i.	(1•5 atm)
	(see also page F12)
ELECTRICAL EQUIPMENT (6 volt)
	Battery	Lucas 6 volt PUZ5E/11
	Alternator type	Wipac 1G1768
	Contact breaker unit	Wipac S0584
	Ignition coil	Wipac S0769
	Rectifier	Wipac S2642
	Bulbs:
	(headlight, main)	30/24 watt pre-focus
	(headlight, pilot)	3 watt M.E.S.
	(stop/tail light)	6/18 watt S.B.C. staggered pin
	(speedometer light)	0•6 watt B.A. 7S lug cap
	Horn	Clearhooter HF900

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D14/4	GENERAL DATA	GD7

CAPACITIES
	Petroil proportion	See page A3
	Fuel tank	1•875 gallons or 2•25 U.S. gallons	(8•5 litre)
	Gearbox	Ύ-pint	(0•5 litre)
	Front fork (each leg)	-pint	(0•07 litre)
BASIC DIMENSIONS
	Wheelbase	50•0"	(127 cm.)
	Overall length	77•5"	(196•85 cm.)
	Handlebar width	27•75"	(70•49 cm.)
	Seat height (unladen)	31"	(78•74 cm.)
	Overall height (approximate)	40•0"	(101•6 cm.)
	Ground clearance	6•75"	(17•15 cm.)
WEIGHTS
	Machine (unladen)	215 lbs.	(97•5 kg.)
	Engine/gearbox unit (less carburetter)	51 lbs.	(23 kg.)

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D14/4	GENERAL DATA	GD8

D14 BANTAM SPORTS MODELS
All general data is the same as that given in preceding pages for the Supreme models except for the following:—
CARBURETTER
		Concentric R626/13
FRONT FORKS
	Shaft diameter	1•248—1•249"	(31•70—31•72 mm.)
	Sliding tube bore	1•475—1•477"	(37•46—37•51 mm.)
BUSHES
	Upper bush (outside diameter)	1•4750—1•4755"	(37•465—37•477 mm.)
	Upper bush (bore)	1•250—1•251"	(31•750—31•775 mm.)
	Working clearance	0•001—0•003"	(0•025—0•076 mm.)
	Length	2" overall	(28•5 mm.)
	Lower bush (outside diameter)	1•473—1•474"	(37•44—37•41 mm.)
	Lower bush (bore)	1•2485—1•2495"	(31•714—31•737 mm.)
	Working clearance	0•001—0•004"	(0•025—0•102 mm.)
	Length	1Ό" overall	(31•75 mm.)
WHEELS
	Spoke sizes:
	(front, left-hand)	12 s.w.g. Χ 6-21/32"	(2•641 Χ 169•069 mm.)
	(rear, right-hand)	10 s.w.g. Χ 6-9/16"	(3•251 Χ 166•687 mm.)
BASIC DIMENSIONS
	Seat height (unladen)	30•5"	(77•47 cm.)
	Handlebar width	23"	(58•42 cm.)
	Overall height (approximate)	37•5"	(95•25 cm.)
WEIGHT
	Weight	221 lbs.	(100•24 kg.)
CAPACITY
	Front forks (each leg)	pint	(0•175 litre)

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D14/4	GENERAL DATA	GD9

D14 BUSHMAN MODELS
All general data is the same as that given in preceding pages for the Supreme models except for the following:—
BEARING DIMENSIONS
	Forks	As Bantam Sports models
CARBURETTERS (Concentric)
	Type	Amal R626/12
TRANSMISSION (Standard D14 Bushman models)
GEAR RATIOS
		As Bantam Supreme models
CHAIN SIZES
	Transmission	•500 Χ 0•205" Χ 120 links
TRANSMISSION (D14 Bushman Pastoral models)
GEAR RATIOS
	Gearbox	As Bantam Supreme models
	Overall—(top)	8•10 :1
	—(third)	10•54 :1
	—(second)	14•83 :1
	—(first)	23•03 :1
SPROCKETS
	Rear wheel	58 teeth
CHAIN SIZES
	Transmission	•500 Χ 0•205" Χ 126 links
WHEELS, BRAKES AND TYRES
WHEELS
	Rim size and type (front)	WM1-19
	Rim size and type (rear)	WM2-19
	Spoke size:
	(front, left-hand)	12 s.w.g. Χ 8"	(2•641 Χ 225•42 mm.)
	(front, right-hand, inner)	12 s.w.g. Χ 7-1/16"	(2•641 Χ 179•38 mm.)
	(front, right-hand, outer)	12 s.w.g. Χ 7"	(2•641 Χ 177•8 mm.)
	(rear, left-hand)	10 s.w.g. Χ 6-29/32"	(3•251 Χ 175•42 mm.)
	(rear, right-hand)	10 s.w.g. Χ 8Ύ"	(3•251 Χ 222•25 mm.)

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D14/4	GENERAL DATA	GD10

TYRES
	Size (front and rear)	3•00 Χ 19"
	Pressure (front)	17 p.s.i.	(1•2 atm)
	Pressure (rear)	22 p.s.i.	(1•5 atm)
ELECTRICAL EQUIPMENT (Direct Lighting)
	Alternator type	Wipac 1G1791
	Contact breaker unit	Wipac S0584
	Ignition coil	Lucas 3E.T.
	Bulbs (headlight, main)	24/24 watt pre-focus
	(The battery, rectifier, headlight pilot bulb       and horn are not fitted to these models)
BASIC DIMENSIONS
	Overall length	78"	(198 cm.)
	Handlebar width	28•5"	(72 cm.)
	Seat height (unladen)	30•5"	(77•5 cm.)
	Ground clearance	10"	(25 cm.)
	Overall height (approximate)	40•5"	(103 cm.)
WEIGHT
	Machine (unladen)	222 lbs.	(100•5 kg.)