MAINTENANCE INSTRUCTIONS
Click on the different areas of maintenance to access the specific information:
The cylinder and big end bearing are automatically fed by the petrol fuel. The crankshaft main bearing and gearbox assembly are fed by the crankcase oil. The crankcase capacity is 2 1/3 pints SAE 30 oil and should be checked every 600 miles to ensure that the oil level is correct. The crankcase is filled through the filler cap on top of the crankcase. Fill to the level hole, replace the plug, and add a further 1/2 pint. Every 6,000 miles completely drain the crankcase, flush and refill.
To check the contact breaker points for the correct gap, first remove the flywheel cover, the left hand side of the crankcase. This exposes the flywheel. There are two marks on the flywheel, A and O and one mark on the side of the crankcase O. With the A on the flywheel in line with the O on the crankcase, the contact breaker points for one cylinder should just about being to open, and with the two O marks in line the points should be fully open. The gap can now be checked; this should be .0012". When one set of points has been checked, turn the flywheel 180 degrees and then check the other set.
Remove the flywheel, using the correct tools to remove the castle nut and extract the flywheel. This exposes the armature plate which is secured by three fixing screws. By loosening the fixing screws the ignition is advanced by turning the plate to the right, and to retard turn it to the left. The magneto contact points should be checked for correct gap every 2,500 miles and cleaned with a soft rag and petrol. If necessary very carefully file the points flat.
The spark plugs should be checked frequently for the correct gap which must be .020-.022" If it is badly worn, they should be replaced. The English equivalent is a Lodge 2 HLN. Ensure that they are clean, free from dirt and grease at all times. If oiled up or have a considerable carbon depost have them sandblasted by a local garage or dealer. Do not over tighten the plugs when refitting.
Every 1,500 miles, the fuel filters should be cleaned. The petrol pipe from the petrol tank to the carburetor should be disconnected, the petrol tap removed and the filter cleaned. Remove the top of the float chamber on the carburator and clean the union filter. Clean out the float chamber. Clean all the jets. The setting for the needle is the second notch from the top, if worn to a point or rounded, replace.
Jet size 60, minimum 45. Throttle slide 55. Needle jet 262. Needle 0.7. position 2nd notch from top.
To ensure the smooth running of the engine and maximum performance, the carburetor must be correctly adjusted. Adjustment is carried out when the engine is hot, preferably after a short journey. Two faults of the carburetor affecting performance are either too rich a mixture or too weak a mixture. The symptoms of too rich a mixture are: oiling up of the plugs, black and sooty plugs and excessive smoke emitted from the exhaust at low speed. Too weak a mixture is indicated by: Poor acceleration, plug color is a light brown with obvious signs of overheating and spitting back through the carburetor. To adjust the mixture there are two adjusting screws on the side of the carburetor, the right hand side of the carburetor on the Formichino, on the left hand side of the carburetor on the Tipo Sport. The screw set horizontally to the carburetor controls the amount of air into the fuel whilst the screw set inclinded downwards controls the fuel micture. With the engine running, screw both the adjusters right in; the engine will now tick over very fast; turn the air screw outwards until the fastest kickover os reached, then unscrew the misture control until the rate of kickover is that desired, not too fast and not so slow that the engine stalls. Screwing the mixture screw fully in gives a richer mixture and increase the tickover, unscrewing it gives a weaker mixture.
The carburetor air filter should be cleaned in petrol every 600 miles.
Every 3,500 miles it is necessary to clean the gas tank by washing in neat petrol.
With all two-stroke engines a regular cause of loss of performance is the build up of carbon deposits due to burning oil. It is necessary, therefore, to decarbonize the engine every 4/5,000 miles. There is a fairly straightforward maintenance job that every owner is capable of doing. First, lay the machine on its side so that it is resting on the crash rail and thepoint of the handlebars. Detach the junction ring of the exhaust pipes from the cylinder barrels; remove the nine bolts securing the two halves of the silencer; remove the cyliner heads; The carbon can be removed quite easily from the exhaust box with a screwdriver or similar tool; scrape the carbon from the cylinder heads with soft metal making sure that the heads are not scratched. Clean the piston crowns of carbon with soft metal; If it is necessary to remove the cylinders to clean the piston the uttmost care must be taken not to damage the pistons or break the piston rings. The piston ring grooves should be carefullt cleaned out with a piece of broken ring, removing all the carbon deposit so that when the rings are replaced they will be quite free in the grooves. Take special care in replacing the cylinders to ensure that the rings are not broken. When the cylinder heads are being replaced the nuts should be tightened progressively, each nut in turn. The junction rings should be firnly tightened to seal off any leak of the exhaust gases.
Adjustment of the clutch is carried out by means of adjuster on the clutch cable situated on the lower half of the crankcase on the right hand side of the machine. This should be adjusted so there is approximately 1/16" play at the clutch lever.
The front brake is controlled by cable and slack is taken up by means of the cable adjuster, situated on the hub, beneath the left fork. The rear brake adjuster is situated just beneath the rear of the left footboard. Check the brake adjsutments regularly to ensure their perfect working order.
The rear suspension chaincase pivots on an eccentric shaft passing through the rear body casting, and the chain is adjusted by turning this shaft by means of the plate siyuated on the left of the casting by the barke pedal. Remove the two screws securing the plate and using a suitable tool, rotate the shaft to the left or right to lacken or tension the chain for correct adjustment. The amount of tension can be checked with the crankcase flywheel cover removed. To replace the chain, remove the chaincase cover to expose the chain, disconnect and remove. When replacing the new chain, ensure that is well greased before assembly.
The setting of the handlebars is adjusted by the clamping bolt on the lower casting. The adjustment of the steering wheel is done by locking rings which are accessible after removing the handlebar castings and disconnecting the speedometer. If the steering is too loose the machine will not be properly controlled, and if it is too stiff, the machine will lose its stability and control. The movement of the front wheel on the fork links can be dampened by tightening the nut on the trailing edge of the forks.
Wheels are of the split rim type and are interchangeable. The rear wheel is removed by releasing three nuts holding the wheel to the hub. With the tire deflated, the rims are split by undoing three nuts holding the rims together. The front wheel is removed by removing the nuts holding the spindle in the leading links, disconnecting the speedometer drive and withdrawing the wheel and hub. The rims are then removed in the same manner as the rear wheel.
It is necessary at intervals to check all the electrical wiring to ensure that is in good condition, that it is not worn or frayd whereby it will lead to shorting. A wiring diagram for the electrical system can be found here.
On pre 1959 models, the headlight swivelled with the sterring, controlled by cables. The cable is adjusted by removing the headlight box, permitting access to the cable. The cable controls the side to side adjustment. On all models up to date, the vertical adjustment is carried out by slackening the two screws, one on either side of the headlight box, and adjusting the dealed beam unit to give the right amount of light throw.
To clean the machine, use a good detergent shampoo with a sponge. If necessary, use one of the patent solvents to remove the grease. Use a good chamois leather to dry. To keep the chromium plating in good condition, clean regularly with one ithe patent chrome cleaners. The alloy parts of the machine such as the crankcase can be highly polished with an aluminum polish such as Solvol Autosol.
At the mileages indicated below, the following maintenance instructions must be carried out: Every 600 miles: Top up oil gearbox. Clean carburetor air filter. Every 1200 miles: Grease all parts, front forks and gear winging arm. Adjust tension on front wheel, if necessary. Clean carburetor and petrol tap and filter. Every 1800 miles: Lubricate flywheel cam. Clean and lubricate the chain. Every 3000 miles: Drain and clean the gas tank. Every 4500 miles: Decarbonize the engine and exhaust; contact breaker points. Every 6000 miles: Clean and lubricate the steering braces and wheel bearings. IMPORTANT:
It is essential, after the first 300 miles, to examine the machine thoroughly and tighten all nut and bolts. All parts are secure on delivery, but in use the parts bed down producing slackness. As a precautionary measure, examine the machine every 6000 miles and tighten parts where necessary.
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