Crankcase

Splitting the crankcase halves is not terribly difficult on both models although it is quite long winded for there are lots of fixing setscrews.

Before you can split them, and they both split horizontally, you must remove the following parts. Remember also that splitting the crankcase will reveal only the crankshaft, bearings complete with connecting rods, gear trains and selecting (but not shifting) mechanism.

Twin — Cylinder head, barrel, pistons, primary drive, clutch, dipstick, starter motor drive chain, dynamo and dynamo cover, gear shift lever — outer cover and mner. (See individual subsections).

Triple — Cylinder head, barrel, pistons, primary drive, clutch, starter motor, dipstick, magneto/alternator with its outer cover and inner, gear shift mechanism, outer cover and inner. (See individual sub-sections).

Triple crankcase breather — the Triple's crankcase breather operates in exactly the same way as that for the later Twin already described with the cylinder head on that model. However, it is located on the crankcase top rather than on the cambox cover. It's next to the dipstick and is fixed by two setscrews. There's a gasket too. Follow the details given for the Twin.

Remove all the 'outside' components included in the two lists just given. You should now have a bare crankcase with no covers or external fitments left. It is permitted to leave the oil pump in situ. The two camchain ends will still be there.

Carefully turn the crankcase over and rest it suitably supported so that you can tackle the multitude of setscrews fixing the two halves together. The number of screws varies, to a maximum of 21 on late Triples. Start undoing the screws around the outside and then start in on the inside ones. Some are recessed, others are hidden. Do not miss the one under the starter motor. Search them all out and remove them. Note what goes where and retain the washers, particularly the dome nuts, steel and copper washers. Once you are absolutely sure all screws are removed, check again. Turn the crankcase over again so that it is now in its proper situation.

With a hide-headed hammer wallop the area around the split in the crankcase to try to create a 'coming apart'. Be sensible about it. Then with a flat-bladed lever, such as a tyre lever, lever the bottom half against the gearbox sprocket. If you are careful, you are not going to break anything because the casting is extra strong here. DON'T stick any levers into the split once it is there. Tap some and then lift the top half up. Remember that there will be a locating ferrule between the two

The Triple's crankcase breather valve components. Those for the Twins are similar, but fitted to the cylinder head's cam cover

Here's the crankcase halves stud which you will miss on the Triple - it's the one under the starter motor

The arrow shows one of the domed nuts under the alternator cover

Check the crankcase halves for 0 rings such as this once used on a late Triple

This Triple camchain pedestal guide is easily removed from the bottom crankcase half halves at the front. Leave the crankshaft, rods, gear trains and all bearings in the bottom half. The positioning of these components is determined by their bearings being pegged in the lower crankcase by half rings. Place the top crankcase half in a safe place. New crankcases do not come in halves — a whole is very expensive.

SEARCH the lower crankcase half and note where every bearing and its bearing half ring is located. Lift out the crankshaft vertically and carefully place it in safety. Pull out the camchain. Retain the half rings noting exactly where they fit — they are not identical.

Lift out both gear trains, leaving the selectors on the shaft below. The selector shaft is removed by pulling out a locating peg which is normally hidden by the primary shaft (gearbox , sprocket end) bearing. Insert a 6mm setscrew into the end of the selector shaft and pull out the shaft, holding the selectors in place as you do it.

The selector drum can then be removed, if you want to go that far. It is not easy and does require a Laverda special tool, (61818979). Undo the drum shaft end nut (left hand thread) which is innermost in the gearbox and then fit the shaft extractor. Extract the shaft peg with a pair of pliers and then extract the shaft. Lift out the selector drum. The crankcase halves should now be clear except that the Twin will have two tin plate baffles in the upper half. These are held in with four setscrews, and centre punched. On the Triple, the pedestal for locating the camchain on the crankshaft sprocket may still be there. Oil filters on both models may also be there. The oil pump may still be there too — remove that.

With both crankcase halves clear you should now set about cleaning them. Use the previously mentioned cleansers and ensure that the mating faces are thoroughly clean, unpitted and unchipped.

Crankcase reassembly is basically a straightforward reverse process and this will be described next. However, you should perhaps read through some of the other sub-sections first to familiarise yourself with individual component refitment. For example, the crankshaft and connecting rods are discussed as is the complete working of the gearbox.

Once you have everything prepared, all the components absolutely spotless, then assemble the lower crankcase half first. Replace the gear selecting mechanism first, then the gear trains making sure all the shims and bearing rings are in the proper place.

Then replace the crankshaft once you have placed the camchain ready to mate up with it. Again make sure everything is right — looks right too. Check the oil seals at each end.

Use a good, sticky but non-setting gasket cement such as Hylomar or Rhodorsil Silicone CAF 1 on the lower crankcase half mating edge. The factory have always used a very effective white cement which has become something of a trade mark for them. (It's known as gorilla snot). Lots of small tubes litter their assembly benches! Place the top half onto the bottom half. Gently tap it down with a hide-headed hammer until it is properly seated. Now check your bench to make sure nothing is left out! Fit a few setscrews, then turn the engine over — bottom up. Now place the fixing screws in their proper place. Don't tighten any of them yet.

NEVER pull the two halves together using the fixing setscrews. Torque every screw — 14.5/18.0 ft.lb. for 8mm screws, 11.5/13.0 for the 6mm screws. Refit the blind nut and brass washer on the rear left.

NOTE: If you have just removed the lower crankcase half because you were only inspecting the gearbox, obviously you offer the lower half onto the upper half. This means extra care to ensure accurate locating of the bearing rings and oil seals etc.

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