Colin Chapman once said: "If you want to go faster, you will have to add lightness". Having recently taken the horsepower route with the new CSR version of Chapman's creation, the Seven, Caterham has now gone back to basics with a new Superlight.
Based on the standard Roadsport, the Superlight gains four-piston AP Racing brakes, Caterham's own close-ratio six speed gearbox, and wide-track, adjustable front suspension. It sits on bespoke 13 inch KN lightweight alloys wearing Avon CR500 rubber, developed as a lightweight road and track tyre for the car and looking suspiciously like a pair of cut slicks. The spare wheel has been ditched in favour of a can of foam, the carpets are gone as are the standard seats in favour of lightweight composite buckets with four-point harnesses and carbon fibre is used for the dashboard, rear arch protectors and front wings.
All this means the Superlight weighs 55Kg less than the Roadsport, which may not sound like much but in the case of such a tiddler actually represents a 10 per cent saving. Less weight means less inertia and less for the tyres to do in simply supporting the mass of the car so they can work harder gripping the road.
This one however has a windscreen, roof and even a heater, adding a whopping 18Kg -- Caterham list options for the Superlight by weight as well as price -- so I made up for it by packing light and skipping lunch. Wearing a tango paintjob, the loud, brash and bright orange Superlight is the automotive equivalent of a footballer's wife so what else is there to be done but thumb the optional red starter button and head cross-country for Cheshire and in particular the A537 Cat & Fiddle road.
From inside it sounds like a Spitfire with the whine of the gearbox, a resonance through the uncarpeted cockpit and stones rattling like bullets off the underside (and on more than one occasion my forehead). From outside it sounds more like a big capacity sports bike and it starts up with that same muted explosion as the engine sucks in a massive gobbet of fuel and spits it out through the beautiful 4-2-1 exhaust. This, combined with a different air-intake help liberate 140bhp and 124lb-ft from the 1.8 X-Power K-series but it never sounded like this in a Rover and the rev counter certainly never flicked round the dial as quickly. It translates into a 0-60 dash in 4.7 seconds, over half a second quicker than a Roadsport with the same X-Power motor. The 130mph speed is largely academic and possibly rather conservative of Caterham (but that's just a guess, honestly officer).
Through town the car grumbles to itself, revs rising and falling from 1,250 to 1,750rpm at traffic lights and the clutch assaulting your nose with its own protest. But it's difficult to resist the occasional blip of the throttle when passing a bunch of schoolkids, making them stop and stare open mouthed. That engine reveals a great deal of flexibility, it's possible to stick it in top around town, smoothing out the power delivery and making it easier to pootle along at urban speed limits.
But the free breathing K-series thrives on revs and when the road clears, dropping down a couple of cogs has a similar effect to poking a Dobermann with a stick. There is an almost VTEC-type surge at 4,000rpm and the exhaust really starts to bellow. The accompanying acceleration rapidly becomes addictive; resulting in an arrival at the next corner at what seems an inadvisable rate of knots.
Fortunately the brakes are superb with plenty of feel even through a pedal not much bigger than a 50 pence piece and resisting fade even after a few runs up and down some Peak District climbs. With just a roll of the wrists, turn-in is instant but on a trailing throttle, the unladen front wheels lend a slightly vague feel to the steering and there's a hint of understeer. Add some power and give the boots some work to do and suddenly all is neutral and the Superlight sticks to a line like a supermodel. Those bespoke boots are so sticky in fact that once round the corner you realise that actually your speed was limited by bravery and respect for the rules of the road rather than mechanical grip.
The power is there to play fast and loose and overwhelm the grip of the rear tyres at least in tight second and third gear corners and roundabouts but it happens so smoothly and progressively that it is easily caught. Besides, showboating, whilst it might look good at a Southend cruise, has never been the fastest way round a circuit or down the road.
Superlight or superbike?
Hacking up and down the Cat & Fiddle road on a fine autumnal day the Superlight was the closest I could get to being on one of the superbikes that come and play on what is one of Britain's best stretches of tarmac. Smooth and well surfaced with a challenging mix of bends and good sightlines, the road is the ideal off-track playground for the Caterham.
And far better to stick to this than typically badly surfaced British B-roads which show up some shortcomings. The stiffer front suspension struggles over rough tarmac, knocking you off line whilst the De Dion rear can hop disconcertingly. Both ends can hit the bump stops hard on undulating surfaces.
Usable every day?
At £19,995 for a self-build (£22,450 for a factory finished version) the Superlight is four grand more than a Roadsport but a whopping £11,000 cheaper than the new CSR200 and as such can be seen as a bit of a bargain track day tool. As a road car though it can, even in Caterham terms, seem a bit rough and raw. It is very loud and the seats become uncomfortable after a couple of hours but going for a few of the soft options when ordering it should sort out those niggles.
Not quite the 'usable, everyday sportcar' that Caterham's PR claims, but not far off.
Pictures by Gerry Biggs