The engine:

As most of you who have found your way here probably have some idea about the Mini Motor I don’t propose to give a detailed history. The ‘Mini Motor’ section of the web’s ‘The Moped Archive’ will give you more information than you probably ever really wanted to know. ‘The Stink Wheel Saga – Episode 1’ by David Beare, Andrew Pattle and Philippa Wheeler (2004) describes the cyclemotor boom in book form and has a whole chapter on the Trojan Mini Motor.

Very briefly the Mini Motore was designed in Italy by Vincent Piatti as an auxiliary engine to drive lathes and similar devices. Its possibilities as a crude way to motorise a bicycle were quickly apparent and may have influenced the design. It is quite ‘large’ for a cyclemotor with a bore and stroke of 38 x 44mm giving 49.9ccs.

Its beauty is its simplicity. The crankshaft has a magneto on one end and the drive roller on the other. The two stroke engine is ‘piston ported’ so cut outs in the cylinder walls align with cut outs in the piston to allow pressurised mixture in the crankcase to be forced up into the cylinder. There are therefore just three moving parts: the crankshaft, connecting rod and piston. (This is not quite true as a set of points, activated by a camshaft cast into the magneto side journal of the crankshaft, time the spark.) The carburettor, which is needleless, is unusual in that turning the air filter adjusts the mixture to the engine and is used to fine tune the engine once warm, weaker on the flat and richer for the hills. With practice this can be done ‘in-flight’ by stretching a ‘blind’ left hand behind you while controlling the bike with the right.

Image from: http://www.Buy_Vintage.co.uk

The tank acts as the engine mounting frame and is hinged from the seat post. A cable to the handlebars operated by a large lever with a catch raises and lowers the engine. The engine was built from 1949 to 1957 and its ancillaries were developed and improved over the first four years. One of the most significant of these changes was a ‘toggle action’ mechanism which held the engine more positively on and off the tyre.

Mark 5 engine with ‘toggle action’ lowering mechanism. (Photo from the Trojan Motors Museum)

Probably because the position of the engine leaves the bicycle’s own transmission intact (and therefore able to assist the engine through an existing gear system) the Mini Motor was quite a successful as a long distance machine. Three Italian riders rode three machines to the UK in 1948 to find a British manufacturer willing to produce the engine under licence. Once Trojan started production George Murray Denton, an enthusiast for the engine having seen the Italian version in action on holiday in the country in 1948, became sales manager and with a team of other riders promoted the motor in a series of long rides, some against the clock.

A Mini Motor rider clocks in on a timed long distance event in the 50s (photograph believed to be from Denton family archive now owned by Tony Dent)

Motor 1

The engine I originally fitted in 2011 is a Mark 3 (prefix C) sold new in April 1952 in Leeds. ‘If it ain’t broke don’t fix it’ – so apart from adjusting the timing, cleaning the carburettor and changing the spark plug I have left it alone.

I bought it off the son of the original owner. As a boy the vendor lived in Bradford where his father was a school caretaker. At lunchtime the boy used to meet his father who worked in another school not far from the one he attended. When the boy was a young teenager his father was transferred to another school on the other side of the city and lunch together became impossible. Refusing to be beaten, the boy dragged his father’s old tandem from the shed which at that time had the Mini Motor attached. Ingeniously he covered the engine (which he was too young to ride) with some home-made cardboard panniers. Lunch with Dad was on the menu again. All appeared to be going well when an apologetic police officer overtook the innocent looking outfit and flagged the young cyclist down. “I am sorry sonny”, he said, “I had to stop you to let you know that there’s smoke coming from underneath your luggage. I think you tyre must be rubbing somewhere.” Further investigation led to the miscreant’s father being fined 17s 6d for allowing a motor vehicle to be used by an unlicensed driver.

Motor 2 (the spare)

I have built up a second engine to try and head off the bad luck that is almost certain to follow my having left Motor 1 to its own devices. It was an eBay special ‘with compression and a spark’. The seller neglected to mention that it also had a cracked cylinder head, damaged piston and broken Woodruff key which ensured that the spark wouldn’t actually have made the engine run. Luckily a misspent middle age has left me with a large plastic box of Mini Motor components and the engine runs now although not as well as the original.

One crucial factor in the LEJOG ride with be the roller’s relationship with the back tyre. Trojan produced three types of roller: the ribbed (as in the picture from Vintage Bikes), the carborundum and the herring-bone. The first grips moderately but wears very quickly, the second grips well but destroys the tyre and the third neither grips particularly well nor wears the tyre rapidly. Motor 1 has roller type one and Motor 2 has type three. This should ensure 850 miles of roller slippage but not too many new rear tyres (which are a pain to fit).

Motor 2 on its first proving run – that power! That sound! That vibration!

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A particular history of the Rudge Pathfinder

Although the Rudge has been in my extended family since new, until recently I knew very little of its first decade apart from the fact that it had originally been bought by my Uncle Bob. Recently, however, my cousin Sue Langford turned up these photos of Bob and Kathleen on a cycling holiday in the very early fifties.

This is what the Pathfinder was intended for and the pair cycled from the Hampshire – Dorset border along the South Coast and into Devon. They then headed up to reach the North Devon coast. There is no photograph of them with the bicycles as far as Sue knows. It was not about the bike… Except that talking to my Aunt Kath recently she said that they enjoyed the trip but returned never intended to repeat it. Cycling in the Devon hills had been really tough.

Bob and Kath met at a youth club and it seems likely that group cycling, which was very popular at the time, may have been one of the activities. After they married in 1953 the cycle was relegated to more mundane duties and that by the end of the fifties was surplus to requirements. As far as I know neither of my cousins, who are both younger than me, remember Uncle Bob owning the Rudge.

I believe I remember my father having a black bike before the Rudge and him riding to nursery with me before I started school in 1958 but I can’t be sure. The Pathfinder was following the general trajectory of cycling in the late 1950s and was bought by my father to cycle to work. I know my father valued the quality of the Rudge but what preserved it intact into the millennium was an unwillingness on his part to replace or indeed spend any money on it. During the forty years of his ownership it gently decayed: the four gears became three, the Brooks saddle hardened and cracked and the frame lost its bright blue, fading to silver and then the black of its undercoat. The lights ceased to illuminate, the tyres cracked and the wheel rims rusted. Through to the early seventies it commuted to work on fine summer days but a move to North Devon (again!) meant it saw little use. When my parents retired to South Devon it returned to use for shopping trips until developments in cycling finally overtook it and it was replaced by a 21 gear hybrid.

Initially I asked Father for his old bike simply to stop it being scrapped although he was not exactly known for recklessly discarding possessions. It was only after he had suffered with Alzheimer’s for a number of years and no longer knew me that I thought about reviving the old Rudge as a way of maintaining contact with my memories of him.

To be honest motorising a bicycle ruins it and the better quality the bicycle, the worse the sacrilege. I knew I wouldn’t use the bike as it was, however, and discarding everything except the frame and rebuilding it as a modern bicycle seemed to miss the point. I had already owned a couple of Trojan Mini Motors on other cycles, one of which Father had ridden in a few old bike events, so buying a third such engine, while it hardly suggested wisdom, was appropriate.

In its new guise the old Rudge took part in four adventure in 2012/13. It completed the Sars Poteries Rally in northern France twice, stormed the 100 mile cyclemotor run and managed the NACC Coast to Coast Hartlepool to Whitehaven event run over two days via Alston and Hartside. The first of the Sars Poteries runs was touch and go, largely because it had taken me seven years to renovate my first Mini Motor engined bicycle (A car had run over the frame and flattened it) so this time I just bolted the engine on and went for it. It is surprising how frightening a bicycle stuck at a permanent 20 miles per hour can be. By the Coast to Coast it was the inadequacies of the system rather than any particular weaknesses in this particular example that had become glaringly obvious. I had done the ride before on my original Mini Motor but it had been in warm, dry weather. Mercifully I have largely forgotten the torment of getting the Rudge up some of those hills in the mist and wet. There will be plenty of opportunities to recollect after 13th April.

An Aside

If, on reading the previous post, you found it surprising that it was necessary for me to apologise for the fact that my old bicycle claimed to be a ‘Rudge’, you might need an explanation.

Not only is the world of old bicycle and motorcycle enthusiasts divided into competing sects and churches based around different marques or countries of manufacture but also, as with any other human activity, it has been necessary to construct a class structure to rank these enthusiasms into a recognisable hierarchy. At the apex of the triangle are marques that, for example, had an illustrious racing history, were exclusive and expensive in their day or were particularly technologically sophisticated. At the base are small capacity two stroke machines of purely utilitarian design. Even if all this is news to you, the position in the hierarchy of a ‘bogus’ Rudge with a 49cc two stroke engine driving the rear wheel by means of a roller is probably apparent to you.

The original Rudge Whitworth company on the other hand is, if not aristocracy, then at least gentry. Dan Rudge was one of the pioneers of the British bicycle industry and, although his early death (in 1880) precluded him taking full part in the development of the safety bicycle, the company he founded played an important role. Rudge Whitworth formed in 1894 went on to produce what they modestly described as ‘Britain’s Best Bicycle’.

Moving into motorcycle production before the First World War they introduced the Rudge Multi which offered differing ratios on the belt drive by means of an expanding pulley and won the 1914 Isle of Man TT. After the war they became well known for their spoked wheels for cars. In the late 1920s and early 1930s they built sporty motorcycles in the 350cc and 500cc class with four valve heads in parallel and later radial configurations. With these machines they again won their classes at the TT.

Rudge Whitworth had cachet and class. Their Wikipedia entry, although it acknowledges a decline, doesn’t even stoop to mention the acquisition of the name by Raleigh. Like a poor relation at an illustrious family funeral my poor old Raleigh Rudge has been looked straight through.

A generic biography of my LEJOG bicycle

Attending a gathering of old motorcycle or cycle enthusiasts is rather like going to an ecumenical meeting. As you enter all seems peace and harmony but as you circulate you sense the depths of the schisms and divisions that lie under your unwary feet. So, although it says ‘Rudge’ on the headstock of this bicycle, no devotee of the true Rudge Whitworth faith would acknowledge it as anything other than an illegitimate progeny.

The Rudge Whitworth company was sold in 1935 to EMI and then again in 1942 to Raleigh. The production of all vehicles for private use was practically discontinued in Britain during World War II and fuel for private motoring was unavailable so cycling flourished. In the years of shortage after the war the cycling boom continued and cycling clubs were popular with young adults. This was Raleigh’s ‘hybrid’ bike of that period. It was possible to commute to work on it during the week but it was sophisticated enough to take out on club rides at the weekend.

The Raleigh Lenton Sports (model no 28) was announced in 1948 to sell in the middle price range of quality mass-produced bicycles at £14 16s. The Rudge Pathfinder (no 128) along with the Humber Clipper (no 328) were simply re-badged versions of the Lenton featuring different colour schemes, respectively: green, blue and lilac. The frame was made of Reynolds 531 tubing, essential for any bicycle with pretensions to performance at the time. There were steel drop handlebars, a dynamo in the front hub for the lights and a four speed Sturmey Archer gear in the rear hub. All of which rather negated the effect of the weight saving tubing used in the frame. This 1949 model has aluminium mudguards but later production models were equipped with celluloid guards. Frame colours changed over the years with the Pathfinder in gold and then eventually maroon but this was one of Raleigh’s most successful models with a production span from 1948 – 1963. Women’s framed models of the cycle were also produced providing an excuse for an excruciatingly patronising piece of copy from Raleigh.

My uncle and father’s bike remained in a totally original and untouched state until it was motorised in 2011 and there are a few places, originally covered by clips or brackets, where you can still see the vivid bright metallic blue of its paint.

(The information here is indebted to Peter C. Kohler’s article ‘The Raleigh Lentons’ on the late Sheldon Brown’s Retro Raleighs website.)

LEJOG by Cyclemotor supporting Alzheimer’s Research UK

I say, isn’t that rather cheating? (1)

My donation page (https://mydonate.bt.com/fundraisers/raleighrudginit) is telling me that there’s 82 days until the 13th April start of the excursion so time perhaps for a little information on my means of transport.

Looking like an exhibit in a bizarre museum, the old Rudge awaits the spring.

The title is something a well-dressed woman, ducking into a pub on the main street of Heskett Newmarket in Cumbria one Sunday lunchtime, shouted after me as I assisted a labouring engine up the not inconsiderable incline. The answer is both yes and no.

Yes it is cheating, because on a level plain a Mini Motor rider can sustain a speed of 20+mph without pedalling once the bike has been propelled to a sufficient speed to start the engine. The engine is of a very simple design and can be fairly reliable. As a two stroke there’s no valve train to worry about and no clutch or gearbox.

No, it’s not cheating because adding an engine on the rear carrier of a push bike turns a lightweight, smooth running, fleet of foot almost-being into a noisy, unstable, vibrating, smoking contraption. The drive is by roller onto the rear tyre and unless it’s completely dry slips leaving the engine revving wildly while progress slows. The effect of carrying the weight of a medium sized sack of potatoes at almost saddle height is to ruin the handling of the machine making for wobbly starts and uncertain stops. The brakes were never intended for these speeds or this additional weight and the rear wheel rim is constantly showered with unburnt two stroke fuel (which contains oil) and a fine coating of minced rubber particles which the roller chews off the rear tyre. And then there’s the hills… Although the Trojan Mini Motor has a healthy (for this type of design) 49cc, below about 12mph it has no torque. This means that to climb a hill it needs to be kept at this speed whatever the gradient. Bikes of this era had only either three or four gears so in hilly country the rider is left breathlessly windmilling the legs to keep the machine, which weighs approximately 50% more than a normal bike, to a velocity which it is almost impossible to sustain for any length of time with the gearing available.

There’s very little to go wrong but it almost invariably does. For a start almost everything on the engine is at least 60 years old. The tiny carburettor blocks its jet and starves the engine or the float sticks and floods it. The magneto readjusts itself or the woodruff key breaks so the spark happens at the wrong moment. If all else fails and the engine needs a break it will seize solid only freeing off when it has cooled. A bicycle was not designed to carry this extra weight constantly, nor to be ridden at these sustained speeds nor to be subject to constant high frequency vibration. Nuts come undone unexpectedly, mudguard stays mysteriously fracture, frames break and potholes encountered at speed become the stuff of nightmares.

There will be days, believe me, when it will feel like I am cheating shamelessly but there will be other dark dreary hours when I would cheerfully hacksaw the engine into four neat pieces and chuck it over a hedge to continue on my way on the unencumbered bicycle.

LEJOG by cyclemotor 13th April – 9th May 2018

Raleigh Rudginit not trudgin’ itan excursion by cyclemotor from Land’s End to John o’ Groats

The Plan:

Making a rather inauspicious start on Friday 13th April 2018, the plan is to try and ride a 1949 Rudge Pathfinder bicycle fitted with a period 1952 Trojan Mini Motor from farthest west in England to furthest north in Scotland. Generally the route and the overnight stops are those suggested in Lonely Planet’s Cycling Britain (2009) for the Land’s End to John o’ Groats (LEJOG) route. Pausing for a couple of days to put the bicycle on show on the National Autocycle and Cyclemotor club (NACC) stand at the 38th Carole Nash Classic Motorcycle Show on 21st – 22nd April at the Stafford County Showground, the LEJOG route will be re-joined to continue north to Edinburgh on Monday 23rd April. At the end of the week, all being well, the bicycle should arrive in Edinburgh where a couple more days R&R will be enjoyed before the assault on the final and most testing phase of the journey. Both the cycle and the motor are slightly older than I am but I will attain my old age pension during this section of the route. The journey is an excursion rather than a race or an endurance trial and this blog will record the highs and the lows of the experience.

The bicycle has been in my family from new. It was bought by my uncle, husband of my father’s sister, and later sold to my father around 1960. He rode it in an increasingly deteriorated condition for 40 years. When we finally persuaded him to buy a modern hybrid bike with six times the number of gears on the old Rudge, I begged it off him. Unfortunately within a few years he became incapacitated with Alzheimer’s. In 2011 I decided to get the old bike going again and to motorise it with an engine of the same period. Father had ridden an old Sunbeam I had fitted with a Trojan Mini Motor in the past and that seemed the obvious route to take. Bicycles fitted with petrol engines have to be registered in the UK. The Rudge was granted its own registration mark in October of that year. My uncle outlived my father by a couple of years but sadly at the very beginning of 2017 he passed away also suffering from dementia.

The Charity:

It is customary for those attempting LEJOG to nominate a worthy cause to which those in amusement, amazement or just quietly giggling behind their hands at the endeavour might wish to donate a small sum. It was obvious that one of the charities devoted to alleviating or combating dementia should be nominated in this case. I have chosen Alzheimer’s Research UK. ARUK is the world’s leading dementia research charity dedicated to causes, diagnosis, treatment, prevention and cure. The vision of the charity is a world where people are free from the fear, harm and heartbreak of dementia. Amen to that. The address for donations is: https://mydonate.bt.com/fundraisers/raleighrudginit