Instruments and instrument lighting

Early Twins were fitted with a pair of Smiths instruments — a rev counter and speedometer. Both were cable driven as were the Nippon Denso instruments which replaced them. The first Twin with ND instruments was frame number 7056, an SF, in the autumn of 1971.

Four basic speedometers were supplied by Smiths Industries between 1967 and 1972 — 3000 sets were supplied in both 1971 and 1972. The first two instruments were SSM 5001-09 and -10 (mph and Km/h instruments) of 80mm in diameter. Both had black dials with red pointers. They were replaced by SSM 5001/14 and /15 respectively. They were identical except they read to 150 mph/240 Km/h instead of 125 mph/180 Km/h. All were geared to 1000 turns per mile. All four instruments are now obsolete, and are replaced by SSM 5007/00 and /03.

The rev counter was RSM 3005-11(A), a similar unit, with 3:1 clockwise rotation and a reading to 10,000 rev/min. It is now obsolete and replaced by RSM 3033/14. Smiths are not happy about the long term supply of spare parts. If in doubt, look for a replacement from Triumph!

These Smiths instruments were fitted individually by a special rubber band mounting fixed to the top of each fork stanchion. The top cap clamps the mounting to the top yoke. The instrument is suspended in the mounting ring on a drilled disc through which its studs are fixed, via a stretched rubber band clip to the mounting. Removal and replacement is quite straightforward. Watch the trip screw and the wiring. Obviously the respective cables must be released. The bulbs are push-in to the underside of the instrument. Rubber band replacements must come from sources such as domestic appliance (Hoover Junior vacuum cleaner?) suppliers now.

The ND instrument pair are visually similar but actually very different to those coming from early Honda 750s although early ones do have the Laverda stamp on their face and can be considered to have been made specially. These instruments can be swopped from Twin to Triple for their drive ratios are the same. They can be considered to be reliable and easy to read although they do like to be cushioned from vibration. To this end it can be seen why the factory changed mounting methods in 1975.

The early mounting was undamped, its fixing being underneath the two handlebar clamps. The instruments were clamped in two hoops direct to the mounting. Each unit did have a rubber band around it but this did not provide enough cushion. Not only did instruments fail but the mounting used to fracture under the handlebar clamps. The later mounting was one which was bigger, incorporating the handlebar clamps and providing hoops which were rubber mounted at three points. The instruments still had their rubber bands too. It is possible and almost essential to fit the later mounting to early machines, even if it is not perfect. The front, central mounting can still fracture. The instruments are heavy. They are not easily clamped by the hoops on either method. Both are fiddly and great patience is necessary to achieve a proper fixing. Its quite obvious which screws fix the later hoops. The early ones were simple, crude, clipped-in fittings. It helps to use some rubber lubricant to ease the instruments into place.

Access can be gained to the instrument bulbs by undoing the two minute cross-head screws which fix to underside dome-shaped covers (in chrome). Once these have been eased out of the rubber bands the bulbs will be obvious. They pull straight out.

NOTE: Never work on the instruments without being prepared to loosen the handlebar clamps. Always make sure everything is in place before using the machine. Remember that on some machines the rev counter drive cable is the one which earths the rev counter's dial light.

Repairs are not possible; replacement is the only answer. Replacement instruments may not tie up with your wiring loom — you will have to make do. SFC instrument mountings and equipment has varied over the years. Sometimes only a rev counter was supplied; sometimes both rev counter and speedometer. Whatever, it is possible to mount both instruments to the top yoke even if clip-ons are still used. One single instrument mounting was a crude but effective right angle clamp with the rev counter studs sitting in two rubber grommets on the top of that mounting. The mounting was clamped to the front of the top yoke.

Switch gear (handlebar)

As the Laverda production has increased so has their standardisation of parts increased. Early machines were equipped with the best of Bosch equipment, except for all SFCs which were CEV.

From Twin frame number 8700. in late 1971, Lucas 'flipper' switches were then used and Nippon Denso switches replaced these for the 1974 model year, although very early drum-braked 1000s were Lucas equipped. The early Bosch equipment worked in co-operation with the Bosch headlamp ignition key. That key switched the lights on leaving the left hand handlebar switch to dip-switch and blow the horn. The right hand switch was the Bosch starter button. The dip-switch was clamped to the handlebar but the starter button was affixed to the front brake lever clamp. Their action is very simple and little more can be described here — they can be dismantled, up to a point. Replacement parts must by now be rare, but ultimately available.

The Lucas equipment was unfortunately no more popular at the time, although subsequently it has been found to be quite reliable except for 'flipper' breakage. Lucas supplied model 169SA, part number 39756 as the right hand flasher/kill button'starter button and model 169SA, part number 39757 as the left hand dip-switch/hornheadlamp flasher. Both were supplied to take their respective levers for drum brake and clutch. Lucas say that these switches are no longer available. Laverda dealers may still have shelf stock, however. Little can be done with this switch gear except to replace it with another sort. Certain Triumph and Norton fitted Lucas components may be able to help you out. Internal repairs are not easy on these switches.

The Nippon Denso switch gear which is similar to that used on some Suzukis was considered to be excellent when it first appeared. It is reliable and good looking. In fact, Laverda were the first Italian motorcyle manufacturer to use top quality switch gear from Japan. The right hand switch consists of the starter button and kill button and sits 'over' the twist grip, as though the whole thing was 'in one'. The left hand switch has the dip-switch, flasher, headlamp flasher and horn incorporated into it. Both switches clamp themselves with two cross-head screws each. (Some early ND dip-switches may have had crossed-over wiring). Maintenance is minimal. It is important to position the switches so that they do not hit the fuel tank on full lock.

NOTE: Some switches will sometimes suffer from water seeping into them. If in this situation, undo the switches and dry their insides. Then smear the switching parts with a little Vaseline.

Always tie the cables emerging from each switch in their proper place with nylon cable ties. Remember that the steering lock has to be thought about.

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