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Starting Up!
Monday 4 August 2008

There is a ritual to starting up an old motorcycle. The sooner it is learnt, the less you feel like you are at the mercy of unseen forces, waiting hopefully for the fortuitous alignment of the stars and for that magic moment to occur when the engine comes to life.

This weekend's relatively successful efforts in the shed brought back memories. My 1931 Lion has been a poor starter from the time I bought it - and I thought naively it was the poor chump demonstrating it for me! A year or so ago I went looking at a Model 8 from the late '20s being offered for sale. The owner told me he had set it up just as the racers used to with no advance/retard lever or air lever - everything set 'just right'. Petrol on, gear lever into first gear and, after walking it for a half-dozen paces, the valve-lifter simply had to be dropped. It started up a treat! The owner demonstrated it successfully. I tried it and it worked. The owner did it again, before taking off around the block. When he returned,  complete with wide grin, he decided he wasn't going to sell after all! Oh well. nice chap, great bike and an afternoon chatting about 'Beams.

So, back to my experiences with an obstinate Lion. Dusting down my notes gathered from a few sources, here's how  I tried to unravel just how to get the blasted thing going ... plus some thoughts from subsequent experience. Good luck!

(1) Pitman's 'The Book of the Sunbeam' (1945 first edition reprint, pp. 12-14)

Pitman seemed the obvious starting point. In summary, the advice is:-

  1. Turn on petrol tap and depress carburettor tickler.

  2. Open throttle lever by 1/6th to 1/8th.

  3. Using the exhaust lifter, smartly depress the kick-starter (on 1939 500 and 600 c.c. Lion side-valve models, do not forget to first raise the compressor).

That's about it, although it does continue helpfully with the following elaboration:

"There is a certain knack in this which one acquires in time. The points to remember are, not to open the throttle lever too far and to release the exhaust valve lifter when the kick-starter has completed about two-thirds of its travel. On no account have the ignition lever more than one-half open. If this precaution is neglected, the kick-starter mechanism may be damaged by the engine back-firing. Should the kick-starter not engage, or appear to stick, engage first gear and move the machine slightly, when it will free itself. Jumping on the kick-starter crank will only damage the ratchet pinion. When the engine has fired, open the throttle lever slightly, and after the engine has run for a few minutes, the air lever may be opened fully and should remain so unless starting from cold."

(2) John Marston Ltd: 'Sunbeam Motor Cycle Manual', 1932

Some copies of the factory's manuals refer  to starting up, and some don't. Here's the advice from the 1932 manual in full:

"Easy starting is mainly a matter of familiarity with one's motor cycle, but it is necessary that everything should be in good order. Two very important points are: (1) the ignition lever must be retarded, otherwise backfires will occur which might cause damage to the starter mechanism; and (2) the throttle lever must not be opened too wide, since the smaller the opening the greater the suction in the carburetter. Usually the ignition lever should be retarded one-half of its full range, and on machines with specially advanced timing for sporting or racing purposes it may be necessary to retard as much as two-thirds of the range to prevent backfiring. The air lever should be set closed when starting from cold but full open for starting when the engine is warm. The throttle lever should be opened very slightly, but the exact position for best results is a matter for experiment. Then turn on the petrol and slightly flood the carburetter if starting from cold. This, however, should be omitted if starting when the engine is warm. Raise the exhaust valve lifter lever and press down the starter pedal. If the teeth of the starter do not engage at the first attempt, do not use force but move the machine slightly whilst in gear. This will allow the teeth of the starter mechanism to engage. If the engine is stiff, operate the starter a few times till the engine is felt to be moving freely. Then give a final swing to the starter, at the same time releasing the valve lifter, and keep the starter at the bottom of the stroke until the engine fires. In the event of a backfire this will prevent damage to kickstarter mechanism.

"If there is any difficulty in getting the engine to fire, look for the trouble amongst some of the following:

  • Over-lubrication which causes the piston to run stiffly.

  • Points of the sparking plug too far apart. The correct distance is about twenty-five thousandths of an inch.

  • Alternatively, if the points are bridged by carbon or oil, the plug must be cleaned.

  • Platinum points of magneto dirty or too far apart. The points should be set to a gauge supplied by the manufacturers and included in the tool kit.

  • Do not alter the setting of the carburetter unless you are positive the fault lies here. The carburetter is carefully adjusted before the machine leaves the works.

  • A choked jet or water in the carburetter. Clean as detailed directions in carburetter handbook.

"Another form of failure is not dropping the exhaust valve lifter early enough in the stroke of the starter. Avoid spasmodic kicks when using the starter, since these fail to attain the desired result. A smooth swing with the valve lifter dropped halfway through is the most effective method.

"For plugs we recommend Lodge H.1 for Models 9, 10 and Lion and Lodge H.51 for Model 90. Racing and severe trials riding require special consideration beyond the scope of this manual."

(3) 'Motor Cycles and How to Manage Them' (1936, p.122)

Contemporary advice from the 26th edition (completely rewritten we are told!) of this classic guide for motorcyclists provides helpful advice for starting up late-vintage machines. Written with the Amal Standard (pre-Monobloc) carburetter in mind, it advises:

"Now, assuming that the gear lever is in neutral - that is, the position between bottom and second gears that allows the machine to be pushed along without the engine revolving - turn on the petrol and, if the engine is cold, press down the little tickler knob to be found on the top of the float chamber of the carburetter.

"Press down the tickler until petrol just starts to exude from the instrument; do not flood the carburetter so that petrol drips profusely. Then place the ignition control roughly in its mid-position. Shut, or nearly shut, the air control and open the throttle about about a quarter of its total movement.

"Next grasp the exhaust-valve lifter (or compression release), assuming one is fitted. Place a foot on the kick-starter and give the pedal two or three long, swinging pushes. As the pedal almost reaches the bottom of its travel on, say, the third kick, let go the exhaust-valve lifter. The engine should start. If it does not fire, the reason probably is that the valve lifter was dropped either too early or too late, or that the so-called 'kick' was not of the swinging variety.

"Once the engine is running, open the air lever as far as is possible consistent with the engine running properly. "

(4) And finally, advice from an 'old hand'

Ray Jones from the Marston Heritage Trust wrote a piece for the Marston Sunbeam Register Newsletter, May 2002 entitled 'Tips for the Novice: Starting a ‘Classic’. Follow the link to read the article.

I found Ray's advice very helpful. It is written from the perspective of a motorcyclist grappling with the real life experience of their machine, rather than impersonal instruction. And, it seems it was written following an episode when even he too had problems starting up his machine (also written up as a short piece in the Newsletter, which is included for light relief).

From my own perspective, the 'knack' between achieving a heart-lifting 'bang' and a demoralising silence, rested on use of the valve lifter - a point made in the Marston's manual. Experience, gained from long sessions of failure, taught me that my most common failing, when everything else was set up right, was to drop the valve lifter much too late.


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