Replacement of front and rear wheels

The sequence of replacement is a very straightforward reverse sequence of removal in each case. On front wheels: drum brakes — adjust the brake cable.

disc brake(s) — torque the caliper(s) to the leg(s). (When tightening the front axle, hold the speedo drive so that it is not able to twist off the speedo

Www Front Fork Components

The front disc brake and wheel system for cast wheel machines using Ceriar fo ■ s Marzocchi fork components can differ slightly). Disc brake wire wheel systems are similar

The Grimeca rear brake components cable). Just tighten the spindle enough to take up the slack between the fork legs and spacers. Then clamp the fork legs. Tighten the spindle nut.

On rear wheels: drum brake — adjust the brake cable and the rear chain.

disc brake — adjust the chain.

Wheel care

Wire spoke wheels need periodic checking for trueness and strength. Do this as described in the Maintenance section. Should the alloy rim become damaged, discard it and have another rim spoked around the hub. Never dismantle the spokes before your wheel builder gets to see the bent wheel — he needs a lacing pattern. Never attempt to repair a bent rim. Order the right spokes — nine types are currently available! Cast spoke wheels are prone to denting and bending but when they break, they break. Check the state of the rims and spokes periodically and make sure that bare alloy does not get attacked by road salt. Seek further advice if your rim becomes chipped or cracked. Under some circumstances, a professional repair can be made. Note that from the spring of 1978 thick web cast wheels superceded the lighter wheels.

Wheel alignment, balancing and trueing

Wheel alignment is essential for smooth running and handling. Perhaps the best way is to mount the machine on its centre stand and use either a piece of string or a straight edge. The latter is hard to come by. over the length required.

On machines with the same section tyres, front and rear, the problems are easy to solve. Wrap the string, or align the straight edge, around both tyres so that it passes under the machine and 'hits' four edges, two on each tyre. The wheels are in alignment when the string is straight, with none of the four points deflecting it, along its course. The same goes for a straight edge. For machines with a wider rear section tyre, a compensation factor has to be worked out or two pieces of string must be used, one each side of the machine (two straight edges?). Use your eye, when using this method, to compensate. Form a symmetrical pattern, side for side.

Any Laverda will benefit from balanced wheels, front and rear. For wire spoke wheels, use coiled lead around the spokes. For cast spoke, use stick-on weights. It's best to balance wheels off the machine, on a rig, but with tyre and tube fitted. With the wheels on the machine, reduce friction as much as possible, by taking-out brake adjustment (drum) or by removing caliper(s) (disc). On rear wheels, it helps to disconnect the chain.

Spin the wheel several times allowing it to stop at its own pace. Note the point at which it has stopped with chalk marks on the tyre — usually it's with the tyre valve at the bottom. Add weights at the top (its opposite position) until the wheel will then stop in ANY position, when allowed to freewheel. IV2 ounce balance weights are available.

Most machines come balanced from the factory but in the event of some change the above method could be useful. Inner tube balance fluids will work to dampen out slight out-of-balance phenomena, but anything radical needs weights. Wheel trueness is an essential factor for any high speed machine. Regularly raise the machine, spin the wheels and check the rims for any irregularities. Remember a misfitted tyre can cause instability too — do not mistake rim misalignment for tyre misfitting.

Small warpage in wire spoke wheel can be taken out by trueing the spokes with a spoke key, provided you have the experience. Remember it will be necessary to remove the wheel from the machine and remove the tyre and tube. It's too risky playing with a spoke key any other way. Once you have gone this far, it may be a good idea to take the wheel to a wheel specialist who can then check the wheel on a jig.

Cast spoke wheels must be replaced if there is any significant damage or warpage.

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