BSA D7 - TECHNICAL DATA; Engine Specifications; Transmission Specifications; Capacities and Wheels

TECHNICAL DATA
Engine Number—on top of crankcase below cylinder.
Frame Number—at top of steering head tube.
Engine:
Capacity . . . . . . . . . . . . . . . . . .
Cylinder bore . . . . . . . . . . . . . . . .
Stroke . . . . . . . . . . . . . . . . . .
Compression ratio . . . . . . . . . . . . . . . .
Piston ring gap . . . . . . . . . . minimum
maximum
S
p
arkin
g
p
lu
g
. . . . . . . . . . . . . . . .
Plug points gap . . . . . . . . . . minimum
maximum
Contact breaker
p
oints
g
a
p
. . . . . . . . . . . .
174 c.c.
61·5 mm.
58 mm.
7·4—1
·009 in.
·013 in.
L7
·020 in.
·025 in.
·015 in.
Transmission:
Gear ratios . . . . . . . . . . . . . . top
second
first
6·58
9·26
17·4
Clutch—friction
p
lates . . . . . . . . . . . . . . 3
Chain size and pitch
front ⅜ × ·250 in. . . . . . . . . . . . . . .
rear ½ × ·335 in. roller . . . . . . . . . . . .
50 pitches
120 pitches
Teeth on: en
g
ine s
p
rocket . . . . . . . . . . . . 17
gearbox sprocket . . . . . . . . . . . .
clutch sprocket. . . . . . . . . . . . . .
rear chainwheel . . . . . . . . . . . .
16
38
47
Capacities:
Fuel tank . . . . . . . . . . . . . . . . . .
Petroil mixture . . . . . . . . . . . . . . . .
Gearbox . . . . . . . . . . . . . . . . . .
Front forks . . . . . . . . . . . . . . . . . .
2 gallons
See pages 12
and 20
¾ pint
⅛ pint each
leg
Wheels:
Tyre size . . . . . . . . . . . . . .
Tyre pressure . . . . . . . . . . . .
Brake size . . . . . . . . . . . . . .
front
rear
front
rear
dia.
wide
3·00—18
3·00—18
17 p.s.i.
22 p.s.i.
5½ in.
1 in.
5
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