SR5
2007
Radical
Owners
Manual.docx
–
issue
1
‐
22/11/07
‐
7
‐
Issued:
21/09/06
GEARBOX
GEARBOX
MAINTENANCE
The
SR5
is
supplied
with
a
Hewland
JFR
six
‐
speed
sequential
transaxle.
Hewland
transaxles
should
have
the
crown
wheel
/
pinion
and
gear
dogs
inspected
for
signs
of
wear
after
every
event.
(Refer
to
the
manufacturers
manual
for
inspection
and
repair
procedures.)
Crownwheeel
&
pinion:
12:34
Crownwheel
&
pinion
ratio:
2.833:1
GEARING
Ratios
in
the
SR5
are
not
controlled,
so
can
an
may
be
changed
to
suit
different
circuits.
The
‘short’
set
listed
below
is
an
option
for
tighter
tracks
(i.e.
Brands
Hatch).
A
gear
ratio
chart
for
calculating
suitable
ratios
is
available
at:
Please
refer
to
Hewland
gearbox
manual
or
website:
for
changing
gear
ratios.
STANDARD
SR5
GEAR
RATIOS
FOR
CARS
BUILT
BEFORE
16/11/2007
Gear
Part
no.:
Ratio
1
st
CS
‐
1608
‐
12:35
2.917
2
nd
FTR
‐
15:33
‐
HUB
2.200
3
rd
FTR
‐
17:31
‐
STD
1.824
4
th
FTR
‐
15:25
‐
STD
1.667
5
th
FTR
‐
17:25
‐
STD
1.471
6
th
FTR
‐
18:24
‐
STD
1.333
FOR
CARS
BUILT
AFTER
16/11/2007
SR5
Ratios
–
16”
rear
wheels
Gear
Short
(option
for
tight
tracks)
Long
(fitted
as
standard)
1
st
12:38
68mph
12:38
68mph
2
nd
14:33
91mph
14:33
91mph
3
rd
15:29
111mph
16:30
108mph
4
th
15:26
122mph
17:27
135mph
5
th
17:27
136mph
17:25
147mph
6
th
16:24
143mph
18:25
154mph
1
Rev
limit
set
to
8,500rpm
SR5
Ratios
–
13”
rear
wheels
Gear
Short
(option
for
tight
tracks)
Long
(fitted
as
standard)
1
st
12:35
65mph
12:35
65mph
2
nd
15:34
84mph
15:33
87mph
3
rd
15:27
106mph
17:30
108mph
4
th
16:25
121mph
16:24
128mph
5
th
19:27
134mph
18:24
144mph
6
th
18:24
142mph
21:26
153mph
2
Rev
limit
set
to
8,200