DRUM BRAKES AND WIRE WHEELS Economy version of popular Yamaha XS400 four-stroke

Press, 24 November 1977, Page 22

DRUM BRAKES AND WIRE WHEELS Economy version of popular Yamaha XS400 four-stroke

By

PETER MINSON

The 350 cu cm machine has traditionally attracted a profitable amount of attention from motorcyclists. That engine capacity embodied the perfect compromise — the looks and the turn of speed of a large machine, combined with the economy of a smaller one. When the Japanese manufacturers entered the scene, they were quick to recognise and capitalise on that trend. Both twostrokes and four-strokes appeared, and reinforced the popularity of the 350 cu cm size with their light-weight frames and manouevrability. Race successes in more recent years, especially by the Yamaha RD3SO, added to the glamour of the capacity, and it was only natural that when the two-stroke, manufacturers began turning out fourstroke machines that the range, should be continued and expanded.

It was in this context that the Yamaha XS4OO — a slightly enlarged version of the traditional 350 — appeared, and impressed riders with its clean lines, speed, and reliability.

Yamaha has just released in this country the updated XS4OO, as well as an XS36O, to carry on the success of the first model. Both are shortstroke, single overhead camshaft, sporty machines, with the angular looks of the last Norton Commandos. The XS4OO comes in two models. The big seller will no doubt be the rac i e r-looking version, which includes light-alloy wheels, front disc brake, electric start and selfcancelling indicators. However, for those who want the power of the 400 twin, but who do not need these extras, and who want to pay a little less, the economy version (the. one tested) will suffice. It is slightly anachronistic for a medium-capacity Japanese machine to appear without such finishing touches, but when all things are considered, the mechanical drumbrakes (twin leading shoe on front) are perfectly adequate, and spoked wheels have been quite satisfactory for the whole of this century. It is thoughtful of a manufacturer to produce an economy version, and it is also a good way of using up old components. The XS4OO has a sixspeed gearbox which is probably smoother than any of its competitors’ efforts. The power lies high in the engine range — from 5500 revs upwards — and the

acceleration is effortless, aided by the gremlin-free gearbox. The suspension is good in all road conditions, and is quite able to take a dirt track in its stride without things becoming uncomfortable for the ride". With its constant velocity M i k u n i carburettors, the XS4OO

has the quiet nut throaty sound of the Honda 350 twin, and, like the Honda, vibrates heartily at low revs. Once in the power band, however, the engine is very smooth. An unusual feature is the fuel tap, which includes a position for priming the carburettors. In this position the fuel will run in even if the

engine is not running. If the main tank runs out while on the run, it is necessary to reprime the carburettors before turning the tap on to reserve tank. Similarly, the carburettors need priming after< a completely empty tank has been refilled (an unusual occurrence .

The choke has "two set positions which control a separate fuel mixture circuit for starting. Hand controls are easily adjusted to suit the rider’s height and grip, and the handlebars are a mass of switches and knobs. The left side bas the light dipping and turn indicator switches, the horn button and a passing button which flashes the headlamp. The right thumb controls an engine stop switch, reminiscent of trailbikes. the light switch, and, on the more expensive model, the starter button. The speedometer includes a trip-meter, and the high-beam indicator is on the tachometer. Between the meters in a neat “T” arrangement are the key (which has four positions, controlling lighting and accessories in various riding and parking situations) a neutral indicator light, an oil pressure indicator light, and the two flashing turn arrows. The fuel tank holds 11 litres and has a locking cap, and the seat, (which flips over to the left-hand-side) and helmet holder

are opened bv the same lock.

The lines of the machine are clean, with no untidy projections. The k i c k-s tarter, pillion footpegs, and centre-stand are tucked well away. The stands limit cornering on the left side, but the economy model has no centre stand.

The parts of the machine which need regular maintenance are easily accessible, and a good tool kit is included. All these trimmings add up to a well designed machine. On long hauls it is comfortable and smooth.

In town it is not quite so much at home. The engine is responsive to the tiniest amount of throttle, which, combined with the powerful enginebraking of a 9.4:1 compression ratio, makes city riding rather jerky and hard to get used to.

I struck trouble with two points which could worry a new owner in city traffic.

When the engine stalled after a panic stop at lights, the gearbox had to be returned to neutral before the motor could be kicked over again. This could have been caused by the tightness of a new gearbox, but is worth watching in a new bike. The other thing was the new tyres, which reminded me on more than one occasion of their lack of use. New street tyres can be, and have been killers. They have little road-holding ability for the first 1000 km, and are another argument for running in a new machine with care and patience. Until the gleaming new surface especially evident on Japanese tyres has been scuffed off, the tyres cannot be trusted, especially' when on smooth, road-carpet surfaces, or in the wet. However, these minor worries can be overcome by a careful owner who wants to learn to use the best points of the machine to advantage. The XS4OO has stood the test of time and will continue to please owners who want a quiet, light touring machine or a fast commuter.