FOREWARD

We advise every rider to carefully study this instruction book before taking the machine on the road for the first time. Primarily written for the new rider who comes to the pastime without any technical knowledge or road experience, the most elementary points are dealt with. The experienced rider is not forgotten however, and no doubt he will be able to gather some information from the perusal of the following pages, this booklet having been most carefully compiled by men of long riding experience, and with a complete knowledge of the Triumph Motor. Intelligently followed it wit] steer the novitiate through the early stages when little difficulties assume a size and shape out of all proportion to their true value.

Remember that every Triumph undergoes severe tests before despatch to you. For instance, should it be found in the final test that the machine is not quite up to concert pitch, or some slight running fault is manifest this is sufficient cause for the machine to be immediately rejected, and it is not passed out until it reaches that high state of efficiency laid down by the Administration.

This rigorous testing ensures every machine leaving the works ready to ride and fault free.

We shall be pleased to forward this booklet to anyone interested post free.

HINTS ON THE MANIPULATION AND RUNNING OF THE 4 H.P. TRIUMPH

The functions of the four cycle engine are so well-known that they hardly bear repetition, but in the interests of uninitiated we will just outline the cycle of operations, taking it for granted that the reader is conversant with the various reciprocating parts of the internal combustion engine, such as the piston, connecting rod, flywheel, etc.

On the downward stroke of the piston a vacuum is formed in the cylinder, and on the opening of the inlet valve a mixture of gas and air flows freely, into the combustion head and cylinder from the carburettor. On the piston reaching the limit of its downward stroke the flywheels have made a half revolution, and the first cycle is completed. The inlet valve closes immediately after this and the mixture is compressed by the upward stroke of the piston. On the piston reaching the top of the stroke the mixture is ignited. This completes the second cycle. The full effect is thus given to the explosion, forcing the piston down on the firing or power stroke, which, on reaching the limit of its travel completes the third cycle. When the piston nearly reaches the bottom of the stoke the exhaust valve opens and closes again dead on top, thus allowing the exhaust gas to escape. This completes the cycle of operations, after which the same order is repeated.

Of course it is understood that the valves are opened and closed at regular intervals through the medium of timing gears, which also regulate the period of igniting the charge.

On taking delivery of a new machine it will be ready for road after filling up with petrol and oil. Remove the filler cap on the tank farthest away from the head of the machine by pressing down and giving a rotary movement to the same. Fill up with petrol, then remove the filler cap close to the head of the machine and fill up with a good brand of water cooled oil (see page 8). It is well to use a funnel with a fine gauze, as this will trap any water or dirt in petrol or oil.

TO START ENGINE

As the engine is new inject four pumpfuls of oil - further instructions on this point are given in a later paragraph.

Place change speed lever in neutral position, namely, the second notch from saddle, lift decompresser with foot or hand. Flood carburettor, give kick starter one push down with the exhaust lifter raised, throttle lever a quarter open, air lever three-quarters open, ignition lever fully advanced, and without again touching the exhaust lifter the engine should start with the first or second push down of the kickstarter. After which the decompresser should be immediately closed and throttle lever gradually closed until engine ticks over quietly. Now hold up the clutch lever, and place change speed lever into low position, namely, as far back as possible toward the saddle, open throttle slightly, and with air and ignition levers still in the same position as stated above gradually let in the clutch, and machine will glide away.

When starting on an uphill gradient, it will, of course, be necessary to open the throttle wider, and greater care should be taken to let in the clutch carefully to prevent engine stopping owing to too great a load
being suddenly placed upon it. After running a few yards change into second gear (in this position the change speed lever is practically upright) and then into top gear, i.e., as far forward as the lever will go.
The exhaust lever should be momentarily raised while operating the change speed lever. An alternative method when changing up is to disengage clutch while operating the speed lever.

The gear lever positions given in the above paragraphs deal with the Triumph 3-Speed Countershaft Gear. With the Sturmey Archer 3-speed the positions are reversed, i.e., low gear, lever right forward, then middle gear, top gear right back, neutral position (for starting up) is between low and middle gears.

Should any difficulty be experienced in starting during the winter months inject a small quantity of petrol through compression tap.

The engine can be started quite readily with the back wheel on the ground, but for the first few times the less experienced rider will find it more convenient to use the stand.

Do not allow the engine to run for more than a quarter of a minute when on stand, and never allow it to race.

Always start on low gear, and drive on the throttle. It is advisable to use clutch for starting purposes only. Do not slip it on hills in lieu of changing down. A variable gear is for the purpose of relieving the engine of too great a load, and as soon as this shows the least sign of labour change to a lower gear at once.

It is a golden rule to remember that when the engine begins to labour it is time to change down, and when the engine races on a low gear it is time to engage a higher ratio.

When wishing to come to a standstill, throttle down, disengage clutch and apply foot brake gently. The engine need not be stopped for a traffic stop.

The Triumph machine is extremely easy to understand, but should any difficulty be encountered in the early stages, do not experiment with the machine, but ask an expert's advice. Also do not blame the machine, as it has satisfactorily passed a severe test on the road jn the hands of an expert before leaving the Works.

LUBRICATING PUMP

This is concealed in the forepart of the tank. All parts are readily accessible.

To operate turn knob, at the same time raising it so as to bring the feather cut on the plunger rod into engagement with the cap, raise plunger gently as far as possible and a charge of oil will be drawn into pump. The pump now being full, depress the plunger and the charge will be forced past the ball valve and lead to the crank chamber by oil pipe. Immediately the oil has passed, the ball valve closes preventing any further oil passing. It sometimes happens that small particles of grit in the' oil do not allow the ball to seat accurately. This is very rare, but when it does occur it is necessary to dismantle the bottom of the pump by disconnecting oil pipe, unscrewing the mill nut, and removing the ball valve from the barrel, wash this with petrol, and see that the ball seats accurately, and replace.

A sure indication of a full charge of oil being drawn in is quickly apparent to the operator, as when depressing the plunger a perceptibly resistance is felt,, whereas with air a slight resilience only is felt. If in doubt, remove the nut which connects the oil pipe to the tank, pull up plunger and discharge contents.

LUBRICATION OF ENGINE

The lubrication of the engine is perhaps the most vital factor in the successful running of a motor cycle. Riders should understand that lubrication is for the purpose of separating two frictional surfaces, and this is carried out by using a good grade of oil.

Should the oil be of poor quality, too thin, or insufficient, it is squeezed from between the surfaces and metal comes into contact with metal causing undue friction and wear, and in the case of a bearing, possible seizure. On the other hand too much oil creates excessive carbon deposit on the top and side of piston and on cylinder head. For the first few hundred miles, that is, until the engine has properly-run in, a speed of 20 m.p.h. should not be exceeded, and at the same time oil should be freely given.

As all oil is drawn off before the machine leaves the works, inject four charges before starting up, afterwards one charge of oil every ten miles solo, and one charge every five to seven miles with side-car, averaging 20 m.p.h., more or less in proportion to speed, load and district traversed. If at any time In doubt as to whether the engine requires more oil, give the engine the benefit of the doubt, the worst that can happen will be a smoky exhaust, whereas the consequence of insufficient oil is far more serious. Equally serious is the effect of using a cheap and unsuitable oil, which is responsible for loss of power, overheating and stiffness in starting.

A fairly safe test as to whether the engine has sufficient oil, is to throttle down, allowing engine to run at a slow speed for about thirty seconds, after which quickly open the throttle and the exhaust should shew a trail of blue smoke.

Stale oil should be drawn from the crank case periodically, after which give engine three full charges, occasionally flush engine with paraffin. This can be done by removing oil pipe and injecting the paraffin through the metal pipe fixed in the crank case on which the oil pipe slides. Revolve engine by hand so that the paraffin is well splashed about; after which thoroughly drain crank case of the residue by removing the plug at the bottom of the crank case, and then inject four full charges of oil. When replacing the plug do not use undue force, otherwise the thread in the crank case will strip.

We strongly recommend Triumph oil as this is specially prepared and is particularly suitable for our engines. We also recommend Price's and Vacuum B.B. We warn riders to reject any oil offered from an open tin or drum, always insist on sealed tins.

For winter, use water cooled. In summer and hot climates air cooled oil can be used with advantage.

OVER LUBRICATING ENGINE

After covering a considerable mileage it is sometimes found that the engine requires oil more frequently. Do not neglect seeking the cause and remedying it. It may be due to one or more of the following causes: -

Deposit oil top of cylinder and piston, faulty plug, platinum points of magneto dirty or worn, accumulation of dirty oil on the back of contact breaker or armature, tappet clearance not correct - stems of the valves should just clear the heads of tappets - valves not lifting sufficiently - correct lift for each valve is ¼ in. - mixture too rich, silencer pipe choked with carbon deposit.

Do not overlook the importance of lubricating other parts of the machine. All bicycle bearings should be oiled regularly, such as, hubs, steering head, control and brake joints, and this is a good opportunity of running the spanner over all nuts to see that they are well home.

DISMANTLING & CLEANING CYLINDER

Remove sparking plug and compression tap, petrol and oil pipes, carburettor, exhaust pipe and silencer which are combined, together with the four cylinder holding down bolts. Lift cylinder clear of the holding down bolts and tilt towards the front down tube of frame, taking care to see that the connecting rod touches the side of the crank case farthest away from the front tube. With a little manipulation the cylinder can then be withdrawn. When dismantling every care should be taken not to damage the surfaces, otherwise after reassembling the owner will be troubled with oil leaking past the cylinder 2nd crank case joint. A paper washer soaked in oil fitted between the joint will cure this.
If the machine has been running any considerable time a carbon deposit will be found on the top of cylinder and piston. Remove this from the cylinder head with the aid of a long screwdriver, protected so as not to injure cylinder wall, and scraps all deposit from cylinder head and valve ports. Burnt oil will also be found in the grooves and behind the piston rings, and to remove this it will be necessary to remove the rings. This can be done without fear of damaging the rings by using three thin strips of metal. Slip -these between the rings and the piston wall so that they are equally spaced and protruding slightly above the top of the piston. The rings being made of cast iron cannot safely be opened out wider than allows them just to slip over the piston head.

In replacing see that they are a good fit in the grooves, free from vertical movement, and if polished all round it will be apparent that they are making a proper contact with the cylinder wall and are gas tight.

The slots should not be in a line, as this will cause the gas to blow past. With the cylinder off it is a good plan to examine the valves. No definite period can be given as to when these require grinding in, as so many factors have to be considered. First remove the valve caps, and then by compressing the valve spring, by means of extractor provided, the cotter through stem can be removed and the valve extracted.

If the face of the valve does not show a bright ring all the way round it is time to grind in, and for this purpose use a prepared grinding compound, or fine emery powder mixed with oil or paraffin. Smear a small quantity of this on the lip of the valve and drop it on to the seat, then with a long screwdriver rotate the valve on its seating, every so often lifting and replacing it in a different place. Before doing this, plug the valve chest with cotton waste or a duster, so that none of the abrasive mixture gets on the cylinder wall. Proceed with the grinding until a bright ring is obtained on the face, then carefully wash away all the grinding mixture with paraffin, and replace valve.

It is more satisfactory to reface valves, which we undertake to do at a nominal cost. This not only saves time in grinding but saves the seatings. It is advisable to grind in a refaced valve.

All will now be ready to replace the cylinder, etc. Do this in the reverse order of taking off, smear the cylinder walls and piston with a little oil beforehand.

In screwing down the holding down nuts give each a successive turn, otherwise by screwing one home by itself, the cylinder is liable to be damaged or warped, and will not bed accurately on crank case.

Now test valves for clearance. The stems should just clear tappet heads when both valves are closed. If there is an appreciable distance between them or the stems are in actual contact, slacken the centre lock nut on the adjustable tappet and screw top nut either to the left or right, to lengthen or shorten. The clearance on the exhaust valve should be slightly greater than in the case of the inlet valve. When correct adjustment is found lock the centre nut to the top one securely. Two spanners are included in the tool kit for this purpose.

VALVE REMOVAL

With the engine in the frame it is rather difficult to remove the valve without the aid of a special tool. With the Triumph valve extractor it is the work of a few moments, and this tool is included in every kit. Proceed as follows; - Turn the engine by means of kick starter until the valve to be extracted is fully lifted and spring compressed, then place the extractor in position, top jaw gripping valve guide with the lower portion hooking under spring cup, again revolve engine, when valve, tappet and stem will fall. The cotter can then be removed and the valve extracted, after first removing the valve cap. With the spring and cup remaining in position it is an easy matter to slip in a new valve, but when time permits it is always advisable to grind this in.

OUTSIDE OF CYLINDER

Remove any encrustation of mud with a stiff brush, as this affects cooling. As the cylinder is made of cast iron wet and heat will turn it rusty on the outside. This will have no harmful effect, but to the fastidious it will savour of neglect. The appearance can quickly be restored by mixing blacklead or lamp black with paraffin and applying the resultant thin paste to the cooling fins with an ordinary brush.

Watch for any stains on the cylinder, particularly round the compression tap and valve caps. Should these be present, it means an air leak, and it will be necessary to screw down more tightly or interpose a copper and asbestos washer.

PISTON RINGS

After running a considerable mileage, the top rings as well as the grooves in piston, will probably show signs of wear, vertical play being the result. In consequence the compression is poor and a peculiar noise arises when the engine is running. The remedy is to fit new rings. For this purpose we supply rings, 5, 10 and 15
thousandths wider than standard.

REMOVING GUDGEON PIN

Care should be taken not to place undue strain upon the piston, as this is very light, and easily distorted. To remove the gudgeon pin tap with a metal punch the end marked out at the same time, get someone to hold piston securely the opposite side, so as to prevent connecting rod and other parts being strained. In replacing, the end marked 'out' goes into the end marked 'in' on the piston. Now test the piston carefully with a pair of callipers and should it be found slightly oval, lightly tap the end marked 'out' on the pin and this should bring it true.

TRUING UP FLYWHEELS

When an engine overhaul is undertaken by the amateur, or the work is carried out locally, we wish to draw special attention to the truing up of the fly wheels, which is an important and difficult undertaking. So as to be able to verify the correctness of the adjustment, a hole is drilled in each of the flywheels through which the valve stem should pass if the wheels are in perfect alignment. Hold firmly in this position, and lock up the crank pin nut, the fly wheels should then be accurately assembled. We advocate the use of valve stem, as the diameter coincides with the holes in the fly wheels, and so obviates the employment of an additional tool.

Although we give above directions, we prefer overhauling the engine ourselves, and in this case, like to have the complete machine, so that we can test the running after the overhaul has been effected, or failing this send fly wheels and connecting rod complete.

VALVE TIMING OF ENGINE

Bore and stroke 85 X 97 m.m. Exhaust valve should open 11/16 in. from the bottom of firing stroke and close dead on top. The inlet valve, should commence to open when toe piston is at the top of the stroke, and close 5/16 in. up the compression stroke.

An alternative method of timing the engine is as follows: - When the engine has been taken down, care should be taken when re-assembling to place the punch mark on the cam wheel exactly opposite the punch mark on the tooth space of the pinion wheel. When fixing pinion to engine shaft the key way nearest the punch mark must always be fitted to the key on the engine shaft.

THE AB0VE REFERS TO 1915 TO 1919 ENGINES ONLY, AND THE FOLLOWING IS THE CORRECT VALVE TIMING OF ENGINES OF PREVIOUS YEARS

1914 4 h.p. MODEL. BORE AND STROKE 85x97 m.m.

Inlet valve commences to open on top dead centre, and closes ⅜ in. up the compression stroke. Exhaust valve commences to open 5/16 in. from the bottom of the firing stroke and closes on top dead centre.

1910, 1911, 1912 and 1913 3½ h.p. ENGINE, BORE AND STROKE 85 x 88 m.m.

Inlet valve commences to open on top dead centre, closing ⅜ in. up the compression stroke. Exhaust valve commences to open 5/16 in. from the bottom of the firing stroke closing on top dead centre.

1908 to 1909 3½ h.p. ENGINE. BORE AND STROKE 84 X 86 m.m.

Inlet valve commences to open on top dead centre, and closes on bottom dead centre. Exhaust valve opens ¼ in. from the bottom of the firing stroke and closes on top dead centre.

1907 MODEL. 3½ h.p. ENGINE. BORE AND STROKE 82 x 86 m.m.

Inlet valve commences to open 1/16 in. down the stroke, and closes on bottom dead centre. Exhaust valve commences to open ¼ in. from the bottom of the firing stroke, and closes on top.

1905 to 1906 3 h.p. ENGINES. BORE AND STROKE 78 X 76 m.m.

Inlet valve commences to open 1/16 in. down the stroke, and closes on bottom dead centre. Exhaust valve commences to open ½ in. from the bottom of the firing stroke and closes on top dead centre.

CARBURETTOR AND MISFIRING

It is necessary that the piston slide valves are a good fit in the barrels, otherwise this will cause air leak, upset the mixture and cause difficult starting. The gauze covering the air intake serves as a filter and should be kept quite clean.

Should the engine develop fitful firing, this may be caused by water in the carburettor, disconnect petrol pipe from tank and unscrew cap over float chamber, the float and needle can then be removed, and the water cleaned out. The removal of the small screw will release any water beneath the jet.

Another cause of misfiring, is for foreign matter to be carried with the petrol to the gauze beneath the jet, this causes partial stoppage and strangles the engine. The obstruction can be removed by unscrewing the jet from the bottom of the carburettor and cleaning gauze. Make sure the stoppage does not exist in the petrol pipe itself. It has been known for a tiny bead of water to lodge on the top of jet after the machine has been stalled for a while. This is a most elusive trouble and will cause failure to start. To remove this, flood carburettor by pressing down tickler on top of float chamber.

Do not reduce or enlarge size of jet: the size fitted gives the best results under general riding conditions, and if tampered with an incorrect mixture will be the result and consequent overheating.

Engine misfiring at slow speeds is an indication that the points of the plug are too close to the central electrode. Also examine and clean the platinum points of magneto, and see that the points are not more than ½ m/m. apart when fully opened. Engine misfiring at slow speeds in earlier models is often due to weak valve springs.

CARBURETTOR FLOODING

This may be caused by needle valve being worn thereby not shutting off petrol supply. A new needle is advisable in this case. If the float is punctured, this will also cause flooding. The correct petrol level is slightly lower than the top of jet.

CARBURETTOR AND TESTING COMPRESSION.

To remove carburettor take off petrol pipe, and loosen hexagon nut adjoining cylinder, the wires can then be removed from handlebar, and the carburettor will slide from the cylinder. The float chamber can be detached from the mixing chamber after removing the latter, by taking off the petrol pipe and loosening square nut which secures mixing chamber to float chamber. When replacing float chamber be careful so see that this is pushed well against the body of carburettor otherwise the engine will eight-stroke at slow speed.

To flood carburettor depress tickler, holding finger over hole at top until the petrol overflows. Do not jerk the tickler up and down as this has a tendency to injure the float and needle.

When testing compression have the throttle open, otherwise a vacuum is formed in the combustion chamber and may produce precisely the same effect as absence of compression.

ENGINE KNOCKING

Should engine knock after slowing down for corners at once reduce the amount of air. This knocking is due to either too poor a mixture too high a gear, or else too excessive carbon deposit on top of cylinder and piston. Roughly speaking the carbon deposit should be removed after every 700 to 1,000 miles.

Another cause of knocking, noticeable only when running down hill, is due to worn bearings or vertical play of the top piston rings in grooves. The above applies more or less to engines fitted with plain bearings.

BROKEN PETROL PIPE

A broken petrol or oil pipe can be temporary repaired by binding same with insulating tape wrapped round in several layers.

FOOTRESTS

Place these at the correct angle and reach to ensure comfort, in relation to saddle position. In the event of a fall the footrests and hangers will be bent, but these being made of a mild steel can safely be straightened with the aid of a large adjustable wrench, using same as a lever.

BRAKES

Inspect these occasionally and keep adjusted close up to their respective rims, and use back brake for regular work, the front one as an auxiliary. Sudden application of the front brake when rounding corners or on grease will cause the machine to skid.

After a while should the brake pads become shiny roughen the surfaces with a file.

ADJUSTING AND REMOVING BELT

It will be necessary to shorten belt after the initial stretch has been taken out, which will occur in the first hundred miles. Every care should be taken to drill holes centrally, and use a punch of the correct angle and proper fit. Many belt troubles are caused by the non-observance of these points. A short length of belt and a spare belt fastener should be carried and used in the event of the ends pulling through. A spot of oil on the belt fastener occasionally will prolong its life.

The belt is more easily detached and replaced over edge of large pulley. Put it on smaller pulley first, and then as far as it will go on top of large one, then wheel the machine backwards and the belt will replace itself.

TYRES

Never ride with the tyres board hard as this will, accentuate vibration and make riding uncomfortable. Neither should the tyres be too soft, as when in this state they are more liable to puncture, and rims will be dented by loose stones. Strive for the middle course. The back tyre may safely exhibit a slight bulge under full load with the machine at rest. The front tyre should be somewhat softer.

With a side-car fitted make sure that it is in correct alignment, otherwise the tyres are subjected to undue wear and severe strain.

It will repay the rider to inspect his tyres occasionally, and remove any pieces of flint that may be embedded. Cuts, if deep, should be cleaned out and washed with petrol and filled with tyre stopping. Should canvas be damaged, back up with a piece of canvas found in any tyre repair outfit.

Do not allow oil to get on tyres, or water or dirt inside. Before removing a cover brush away dirt from rim and cover to prevent this getting inside. When replacing the cover it is advisable to inflate tube slightly as then there is less risk of this being nipped between bead and rim.

TO SAVE TYRE WEAR

Do not accelerate too quickly.

Drive on the throttle not on the brake.

Take corners slowly.

When coming to a halt do not apply brakes too suddenly.

Declutch when running over loose stones.

Do not allow rims to rust inside.

When changing gear endeavour to get a smooth change free from any jerk.

High speeds set up excessive wear.

HOW TO FIND GEAR RATIOS

The method of finding gear ratio between engine sprocket and driving wheel is as follows: - Place machine on the stand, remove chain cover, make a mark on road wheel with a piece of chalk, and a corresponding mark on engine sprocket. Turn the road wheel one complete revolution, and at the same time count the number of sprocket revolutions. If the sprocket revolves five times to one of the driving wheel, then the gear ratio will be five to one.