Lotus Elise Service Notes page 81

Lotus Service Notes Section DE
CG.1 - GENERAL DESCRIPTION
The fully independent front suspension comprises, on each side of the car, upper and lower, fabricated
tubular steel wishbones, with a concentric coil spring/telescopic damper unit picking up on the outboard end of
the lower wishbone. An extruded aluminium alloy hub carrier, houses a dual taper roller bearing which sup-
ports a steel hub equipped with 4 wheel studs. A forward mounted tubular steel anti-roll bar, is supported in
chassis mounted pivot bushes and is operated via short ball jointed drop links from the lower wishbones.
The inboard ends of both wishbones use replaceable bonded rubber pivot bushes to provide maintenance
free articulation, with a specification providing accurate and responsive dynamic characteristics. Both upper
and lower steering swivel ball joints are pressed into housings incorporated into the outer ends of the upper and
lower wishbones. The upper ball pin is secured to the forged steel, rearward facing steering arm, itself fixed to
the hub carrier by two M10 bolts. The ball pin of the steering lower swivel joint is secured in a forged steel plinth
bolted to the bottom of the hub carrier by four M10 setscrews. The spring/damper unit acts between the outer
end of the lower wishbone and the chassis front crossmember, and is fitted with the damper rod lowermost in
order to minimise unsprung weight.
In order to protect the alloy hub carrier from the effects of electrolytic corrosion, it is important to ensure
that the joint faces with any steel components are coated with the specified jointing compound before assem-
bly.
CG.2 - GEOMETRY & ADJUSTMENTS
Provision is made for the adjustment of wheel alignment, camber and castor. Under normal service
conditions, no periodic scheduled check of the geometry is necessary, although a front wheel alignment check
is recommended when the front tyres are replaced. A full geometry check is required only after front suspen-
sion repair, or if excessive tyre wear is evident, or if steering difficulties are encountered. Before any measure-
ments or adjustments are made it is essential first to set the vehicle to its 'mid-laden' ride height, approximating
to driver and passenger and a half tank of fuel:
Ride height (for geometry check) - front
- rear
Alignment
Camber
Castor
Steering axis inclination
140 mm below front end of chassis siderail
140 mm below rear end of chassis siderail
0.2 mm toe-out overall; - 0, + 0.2 mm
(0.03° toe-out overall; - 0, + 0.03°)
-0.1°; +0.1°, -0.2°. Max side/side 0.2°
+ 3.8°; ± 0.2°. Max side/side 0.2°
12° nominal
Alignment
Wheel alignment refers to the parallelism of the wheels when viewed from above and is crucial to vehicle
stability, handling and tyre wear.
Difference between
rim measurements
= overall toe out
FRONT
Individual
toe out
angle
Ic26l
1998 / 02
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