Yokes removal and replacement

So many different types of fork yoke (triple clamp) have been fitted to the Twin and Triple Laverdas that it is not always possible to specify replacement parts just by quoting machine type and frame number. Instead, it is almost necessary to remove the offending components and have them matched!

No owner will want to change the specification of his fork yokes just for the sake of doing so because of their replacement price. Most owners will not be able to judge a difference in specification on the road. Remember that machines with 35mm forks require 35mm yokes and so on. Yokes are interchangeable between Twin and Triple, but because they are parallel bored, they must be changed in pairs.

For safety's sake remove the fuel tank. Remove the handlebars and hang the instruments free. (On the SFC remove the fairing). Remove the forks complete if both yokes are to be changed; if only the top one is to be changed then just remove the fork top caps and loosen the top alien screw (on each side) which tightened the yoke to the stanchion. With an alien key loosen the centre yoke alien screw. Remove the top yoke first. With an appropriate socket loosen the centre steering head nut above the top yoke. (Some early models will have a steering damper adjuster in this position.

Loosen and remove this first, then attack that nut). Remove that nut and that should then enable you to tap up and off the top yoke. Use a hide headed hammer only and go gently around the three locating points (steering head, and both fork stanchions).

With the top yoke removed you will expose the top of the headlamp brackets and/or fork shrouds (not SFC) and the hydraulic brake pipe from the master cylinder to distributor block on the bottom yoke (disc brake machines). If you want to remove the bottom yoke, proceed as follows.

Now hold the headlamp/its brackets/shrouds/flashers to stop them falling off the bottom yoke and then hang the complete business from the front of the engine. The wiring will make this tight. There is no real reason for dismantling the headlamp unit further.

On late model 1000 Triples, disconnect the electrical snap connectors to the horns, and then remove the two horns.

On disc brake machines this will still leave the brake master cylinder hanging from the distributor block. One can assume that the caliper(s) is still hanging from it too. Hold both and remove the distributor block from the bottom yoke. That way you can keep the whole front braking system intact.

On most of the machines there is a little bracket which encompasses the underside of the bottom fork yoke and locates on a bracket on the frame. Remove this now; it's an obvious removal (the clutch cable sometimes passes through an "O" ring welded to it). Undo the adjuster nut on the top of the steering head (normally under the top yoke). Now carefully tap the steering head stem, which has the bottom yoke attached to it, down through the steering head. Use a hide-headed hammer. Watch the bottom yoke as it descends. Replacement is a straight reverse process of that just described. Finally check the tightness of the steering head; it must swing easily, but without any play. The steering head column is attached to the bottom yoke. It can be removed by loosening the alien screw which holds it and by being tapped down and out. Note its exact position.

Steering lock

The steering lock is a very reliable German made Neiman lock. Spare keys are not available — it's people wishing to obtain a key that create the majority of spare lock sales.

Lock removal is quite easy. Carefully drill out the lock's rivetted cover. The rivet comes away easily. Now use a % inch/7mm drill bit and drill out the whole of the lock. Pick out the bits with a small screwdriver and make sure the orifice is clean of swarf.

To replace the lock, have the lock's channel to the top, put the lock into a locked position with the key still installed in it. Push the whole thing home with its spring, and then twist the key and withdraw. The lock is now installed in the locked position. To keep the lock installed without it being in the locked position you must now install the lock's new oval plate/cover. Each new lock comes with all the necessary components including the cover's rivet. Place the cover in its proper position, fit the rivet using a normal rivetting procedure with the washer under the rivet's head.

Now check that it works properly and spray a little WD40 into the lock.

Steering head bearings

With the two fork yokes removed the steering head bearings are exposed. Although these two bearings are not interchangeable, they are removed and replaced in a similar manner. Inside the top caged ball bearing sits a locating collar for the top of the steering column. Pick this out with a screwdriver. Already, with the removal of the bottom yoke, a special collar for the underside of the bottom roller bearing will have been removed.

To remove the bearings, tap them out from their opposite ends, through the steering head itself. Remember that a spacer is fitted on each bearing's inner side. A suitable drift works best; do not use a screwdriver for it may score various components.

Your reasons for their removal will vary although the most obvious one is that they have worn and loosened. Replacing new bearings is straightforward; use a suitable drift to tap them home, and do not forget the spacer. The top bearing is sealed for life so you are not bothered with extra grease.

Steering damper

Early Twins, the 650, 750GT and S, were fitted with a steering damper which worked in the

3. A 1979 Jota with Corte e Cosso rear shockabsorbers

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