Drum brake inspection shoe and mtovxng part replacement

For the purposes of this guide all types of drum brake are the same, as they are front to rear. Remove the relevant wheel, pull of: liae brake plate. Treat the brake plate and hubs with care

The early Laverda rear drum cable fitment and adjustment (Twin)

Laverda rear drum set-up. Note the method of cable adjustment on the drum back plate

The early Laverda rear drum cable fitment and adjustment (Twin)

Laverda rear drum set-up. Note the method of cable adjustment on the drum back plate

— they are very expensive and precision machined. Remember that two shoes must work simultaneously and with equal pressure when you pull one cable. The motion between both shoes in one drum is set at the factory but it can be altered.

Inspect the drum for scoring and ovality. Reconditioning, i.e. skimming, can take place on the cast iron inserts but only so far. If the brake is set up properly, drum life should be very long indeed. Clean it carefully.

Inspect the brake plate and clean off the brake dust. Each brake shoe should be smooth and un-chunked. Each should have a specified thickness. If they have not, remove each shoe.

The shoes are easily removed. Each end of the shoe fits on a pivot pin and is located by a pair of split pins, over a rubbing plate, which are folded over. The early Grimeca drums use the same principle as the later Laverda drums although the components are quite different. They, in fact, use special C clips instead of split pins but it makes little difference. Also each shoe is only fixed at one end while the Laverda shoes are fixed at both. Each shoe is also attached to the brake plate by two 'anti-rattle' springs (better replaced by pull-off springs between the shoes). These need to be undipped. The shoes should then be free for extraction.

The actual moving parts on which the shoes operate are easily and obviously removed.

Remember that these steel parts have somehow to be extracted from the alloy brake plate. Study the relevant drawings with care and it should then be straightforward. Any wear in the moving components will suggest replacement. Remember that the Laverda brake plates have shrunk in steel bushes and these can be difficult.

Most brake linings are rivetted to the shoes although some may be stuck. It matters little which method is used. What is important is that the correct linings are used and affixed properly. If you can, leave this job to someone who is very experienced. Remember that the Laverda drum brakes are some of the finest ever made. After some service they can only remain good if they are properly looked after. Always use the factory's recommended linings. Whenever any disassembly takes place you must re-adjust the brakes when re-assembly takes place. Do make sure that the correct balance exists between the two shoes of one drum. Obviously individual shoe wear will tell you whether you have it right. Uneven wear is the thing to look for.

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