Fork dismantling and assembly

Let's assume that you have removed the slider from the fork leg. Do not turn the stanchion upside down because damper rod components could fall out after the spring. The only further disassembly work on the slider is to remove the fork seal(s). The Marzocchi forks have a damper rod seat located at the bottom of the slider. Most forks have two seals per leg although the early forks and those of the GTL have only one per leg. Each seal is an interference fit even though there is a large circlip fitted above the seals. You cannot remove the seals without destroying them (there's no good reason for doing so unless they are in need of replacement). Release the circlip with a pair of

The last type of Cerlani form as fitted to the 1200. Those used on other models are essentially the same

circlip pliers and then carefully pick out the seal(s) with a pair of pliers and a screwdriver. Take care not to score the inside of the slider. Fork seal replacement is quite easy. Oil the outer edges of the seal(s) and carefully tap them into the leg. A solid wooden drift does the job nicely. On Marzocchi forks the damper rod seat will slide through the seals without damaging them. Always make sure the slider is spotless before replacing seals. Quite a lot of metal swarf can settle in the leg.

To dismantle the stanchion/damper rod further needs care. Further dismantling should only take place if you are sure something is amiss. There is no necessity to do so as a routine maintenance task. For both types of manufacture of forks, take a pair of circlip pliers and remove the circlip at the bottom end of the stanchion. Then carefully pull the damper rod out from the bottom of the stanchion without damaging the rod itself.

In front of you should be the complete damper rod and its bushes and valve gear. Check the

Laverda 650 Vicenza

various components and clean them individually for swarf. Scoring of the components is not desirable. Any badly worn part means that a complete damper rod must be replaced, although it is possible to clean up certain parts with 360/400 wet and dry paper although no dimension should be altered. Certainly do not file or do anything other than wash out the damper rod valve holes. Check the diagrams for your forks before disassembling further, a task which is possible by removing one further circlip. Clean all components once more, including the stanchions and sliders and reassemble everything in a reverse sequence to their disassembly. Go slowly and gently and don't force anything. In the end all the components should be a good sliding fit without being loose. Double check as you go along. The only binding of the fork's action should come from the dust slider. In fact, it is that component which creates the most sticktion. (Remove them and replace them with gaiters). The fork springs sit in the stanchions and they settle after a hard life. Compare their lengths, if they are substantially different (i.e. around 5mm different) replace them as a pair. Most springs will last a long, long time. (Twin and Triple springs are not similar, although they are interchangeable).

NOTE: 35mm Cerianis featured a ball valve pressure release in the top fork nut. Handlebar removal including levers and grips

Handlebar removal itself is an easy task if you simply want to reach the fork top caps. If, however, you want to change the bars or want to remove the steering head bearings of fork yokes, things become complicated. For those with fully adjustable bars and clip-ons, skip the next six points. Various types of levers and instruments have been used and these all make a difference to the methods. Fully detailed procedures cannot be given for each and every model, but basic principles should suffice.

First — on drum front brake models, disconnect both brake and clutch cables at the levers. On disc front brake models, remove the clutch cable at the lever and remove the brake master cylinder from the handlebar as described previously. Disconnect the choke cable at the lever, on Twins only.

Secondly — remove the twist grip. Most of these will split, others will loosen and then slide off. Those machines with integral right-hand-side switches will have no problems, others will now have to unclamp that switch. Watch the throttle cable and electrical wiring.

Thirdly — remove the left-hand-side switch in a similar manner to the other side switch.

Fourthly — disconnect the speedo and rev counter cables at the instruments. These should only be a tight finger thread.

Fifthly — undo the four studs on the underside of the top fork yoke to loosen the two handlebar clamps. For those with separate, loose clamps, remove the clamps. For those with integral handlebar clamp/instrument mounts, push the mount upwards to release the clamps, then carefully hang the instruments on a piece of supporting rag.

Sixthly — lift off the handlebars, once the electrical cables have been loosened. To remove the clutch lever it will be necessary to slide off the left-hand grip. Usually this has to be destroyed as it is removed. The clutch lever will then slide off the bars.

NOTE: Some 750s with Bosch switches have the starter cable inside the handlebar and out through a hole at the middle and then down through another hole in the top yoke. Be careful not to damage the cable there.

(Triples with fully adjustable bars have an easy time. Full handlebar removal can be undertaken as just described, although the bars can be split into five by dismantling them at their adjustment points).

Clip-ons are simpler still, although their removal does entail fork stanchion removal, or at least stanchion lowering.

Effective repairs to any of the handlebar components which may have become damaged in an accident or through fatigue are just not possible unless you are an expert metallurgist or adhesive engineer. Replacement is the only real answer although for early machines original parts may just not be available. Lucas switch and lever gear is practically obsolete now, for example. The now current Japanese switch gear is available while clutch and master cylinder levers are always less of a problem. Never straighten handlebars — throw the bent ones away and buy new.

The Twins, except the SFC, work best with the factory late European SF bend (a superb bar). Apart from the fully adjustable bar fitted to the 1000 Triple, and the 500S Twin bar, no other 'short' bars will work well. The fully adjustable bar is not a good fitting on the Twin because of the shape of the Twin's tank and because the footrests are not in sympathy. The SFC obviously has clip-ons. Most 1000 Triples come with the fully adjustable bar. The early 1200 comes with a GTL type of bar, a bar which does not work as well as that fitted to the Mirage and then later 1200s, a bar similar to the SF and 500S Twin. Replacement of all the components is a straightforward reverse sequence of their removal. When fitting switches make sure that they do not foul the fuel tank on full-lock. For levers, make sure that they work fully through their necessary movement. Make sure all cables have a clear run and do not snag. The factory tend to fit the cables through their best run.

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