Chain

Chain replacement is a straightforward task on all machines.

Find the spring link and have it resting on the rear sprocket. Chock the rear wheel. Loosen the rear wheel spindle nuts. Loosen the chain adjusters. Loosen the torque arm at the brake plate (drum brake) or the caliper carrier lock nut disc brake). On chaincase machines remove the rear cover). Split the chain and place a piece of wire through the bottom of the two loose ends for safety's sake. Now link up the new chain to the top run, unchock the wheel and slowly pull-off pull-on the old/new chain around the sprockets until the old chain is off and the new chain is on. Disconnect the old chain and then link up the two ends of the new chain, again over the sprocket. You should have plenty of room to move as the chain will be slack.

Now adjust the chain. Tighten the torque arm caliper carrier lock nut and replace the chain case end cover (if fitted).

NEVER lose the chain over the gearbox sprocket. It's very difficult to place the chain over it without taking off the gearshift side cover — and that's a long job.

Chain wear is something which is quite easy to detect and then measure. The instant method is to try to pick the links off the rear drive sprocket. If you can, then the chain is worn or badly stretched. If you suspect chain wear because the mileage covered confirms your suspicion, then remove the chain from the machine (as already instructed. The best way of removing a chain is to 'pull it off" with a new one; purchase of a new chain, therefore, becomes inevitable).

Clean the chain in paraffin or cleaning solvent, wipe it doubly clean with petrol, then secure one end of the chain to a flat, suitable surface, and fully compress it so that it appears to be at its shortest length. Measure that length. Then fully stretch the chain and measure that. If the difference in measurements exceeds 6mm per 300mm of chain length, then the chain is worn out. Replace the chain but do not throw it away — it can now be used to 'pull-off all future chains.

Should a rear chain break in service, the chances are it is going to make a lot of mess. If, however, it just runs off and nothing is damaged, you can in theory replace the broken link and refit the chain. I don't advise doing that — fit a new chain, and be grateful no damage was done.

Sprockets

The gearbox sprocket is discussed in the Gearbox section.

The rear wheel sprocket is affixed to the sprocket plate (cush drive) by four high tensile setscrews and nuts. The setscrew heads are locked by two spectacle lock washers. Sprocket changes are straightforward once the rear wheel is out of the machine, although with late drum brake machines it will then be necessary to split the rear chain and remove the sprocket and cush drive (sprocket plate) from the swing arm. Hold the cush drive in a padded vice. Unlock and remove the four setscrews and nuts and replace the sprocket. Torque the setscrews and re-lock the washers using a flat blade screwdriver and hammer.

(For machines with a factory chain case, it will be necessary to split the chaincase body from its back plate).

Laverdas are not unduly hard on rear sprockets but they will need to be replaced after some use. Check for hooked, chipped or worn teeth. Never fit a new rear sprocket without a new chain as well. Fast wear of one or other component will result.

Cush drive

The Laverda rear wheel is fitted with a study cush drive in its hub it consists of eight rubber segments which are a press fit into the sprocket plate's reverse side.

These segments do wear after a lot of use, but are easily replaced, When the segments have become shredded or chunked they are due for repair, and only ever as a set. Push them through with a screwdriver and then press fresh segments back in. A little rubber lubricant may help their installation, but do not overdo it. Of course, once the wheel is removed from the machine, even with either drum or disc brake models, the cush drive is visible.

Factory chaincase and chainguard

The factory chaincase can only be fitted to cast spoke wheeled machines, with rear disc brake. Fitment is straightforward although it is necessary to remove the rear wheel sprocket so to do. A new offside wheel spacer is needed, one somewhat thinner than standard, because of the space taken up by the casting of the case itself.

A little adjuster is fitted to the case to locate it properly and this fits onto the old chainguard fixing on the swing arm. Do not bolt it solid.

Non cast spoke wheel machines are fitted with a more conventional chainguard. Most early Twins, up to the SF3, were fitted with a lower run to the chainguard as well. This fits around the swing arm and locates on the two fixing bolts.

Wheel bearings

The wheel bearings used in Laverda wheels are high quality, sealed-for-life, non-adjustable, ball bearing races. The front wheel uses two races, one, obviously, either side of the wheel hub. These bearings are an interference fit and should be removed and replaced with care. On drum brake machines, take off the brake plate and remove the speedometer drive gear. Tap each bearing out of the hub from the opposite side with a soft drift. Tap new ones back in, fairly and squarely. Note that there is a distance tube in between the two bearings and that a spacer on the inner side of each bearing is fitted.

The rear wheel runs on four bearing races — two in the wheel hub and two in the cush drive. Removal and replacement for both the wheel hub and the cush drive is an identical method to that of the front wheel. Again there are spacers and a distance tube in each component.

It is not necessary to remove the discs on disc brake hubs.

Bearing wear is readily assessable. Place the machine on the centre stand and rock the front and rear wheel, with each one separately off the ground, by gripping the top and bottom of the wheel rim, trying to detect any play. If any play is there, replace all the bearings in the wheel. Rear wheel bearings of cast spoke wheels are subject to greater loads than drum brake wheels and they wear faster.

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