| THE JAP MACHINE |
| Although my account begins in the 1960's, I am going to start with a machine that was not only a dominant force in speedway throughout that decade, but indeed three decades previous also. |
| The idea of the JAP speedway engine was concieved in 1929 by a gentleman by the name of Stan Greening, an employee of a Tottenham manufacturing company, namely John. A. Prestwich & Co. Manufacturers. A keen speedway enthusiast himself and part time machine examiner at the Stamford Bridge track, it was not long before this association led to a meeting between Bill Bragg, the captain of the Stamford Bridge team at that time, and Vivian Prestwich, son of company owner John. |
| John Prestwich eventually but reluctantly gave the go ahead to start developmental work on a speedway motor based on ideas from Bill Bragg and shortly after, the first motor was installed in a frame for Bragg to test. However, this early prototype was not powerful enough nor light enough to keep pace with the technically advanced four valve Rudge motor, which had just dislodged the Douglas twin as the winningest motor of the time. |
| The key came when a successful rider named Wal Phillips, already a regular visitor to the JAP factory took an interest in the JAP developments and agreed to have the factory strip his Rudge motor for some tuning ideas. Many hours of "out of work" time later and a configuratuion was eventually arrived at which looked promising. |
| Indeed, the motor instantly broke the Stamford Bridge lap record in a frame made by a "special" frame builder George Wallis. |
| From those early days the JAP engine went from strength to strength. By the mid to late 1930's most of the bugs had been ironed out and the motor was to prove totally dominant in various guises right through to the mid 1960's. The last model of the JAP speedway motor was released in 1967 and was called the 4B. |
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| Unfortunately, it is here that I must leave the incredible and infamous JAP behind as the next stage in speedway bike history belongs solely to the Czech "ESO" machines, later to become Jawa. |
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| THE CZECH'S ARRIVE! |
| It was 1947 in post war Czechoslavakia to when the first real attempt at producing a speedway motor proper can be traced. A gentleman by the name of Josef Linhart started producing his own speedway motors. |
| Perhaps not surprisingly, he had used the only successful speedway motor of the time, the JAP, as a pattern and his own motors bore an uncanny resemblance. The Czech motors were called the JO-LI (the first two letters of Linhart's first and last name). These motors were produced for the next three years up to 1950 and are distinguishable by their bronze cylinder heads.. |
| It was in 1950 that Jaroslav Simandl, a motorcycle racer of that time who had already dabbled in motor production bought all of Linharts equipment, castings and remaining spare parts and continued production of the JO-LI under the new name of ESO (Czech for "Ace"). |
| In the early 1950's, Simandl's business was Nationalised, but continued to produce a 500cc speedway motor under the ESO banner right up until the acqusition of his company in 1967 by Jawa, an established Czech motorcycle manufacturer. |
| The first of ESO machines to be seen in Great Britain were ridden by none other than speedway legend Ove Fundin. Fundin's first competitive ride on an ESO was actually in Australia in 1961, so it is fitting perhaps that this gels nicely with my story of the speedway machine from the 1960's onwards. |
| In the early 1960's, the ESO motor became very gradually a more common sight on the professional shale circuits and by 1965, the company had a UK concessionnaire, Alec Jackson Ltd of London. Only one year after this in 1966, another speedway legend Barry Briggs became the sole UK distributor of the complete ESO machine. |
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| ESO Motor | Jawa 890 Motor |
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| By the late 1960's the ESO name had been dropped by the Jawa giant and the speedway machines now bore the most recognisable name in speedway even to the present day. The Jawa 890 was mechanically almost identical to the earlier ESO models. |
| The two valve Jawa 890 remained virtually unbeatable for a complete decade to follow. A number of "specials" were built by individuals wishing to improve on the two valves performance, noteably the Neil Street 4 valve conversions, and the Briggo 4 valve conversion. |
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| Neil Street 4 Valve Conversion |
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| No real commercial or revolutionary developments took place on the speedway scene for many years and the 890 Jawa remained dominant until a tiny British firm made a valiant challenge for that supremecy in the mid 1970's. The story of the British Weslake is one close to my heart as it was this machine that I most remember as a young boy stood on the terraces. |
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| THE BRIT'S RETURN! |
| The Jawa domination continued well into the seventies with no mass produced competitor offering any challenge. As previously stated, a number of specials with four valve configuration had shown real promise and the "buzzy" top end power of these units seemed increasingly like the way forward for modern speedway machinery. |
| It was in the early seventies when an engineer by the name of Ron Valentine who was working for Weslake started work on a new four valve powerplant. |
| Founded by Harry Weslake, the organization was well respected in race car circles. The Weslake company was especially proficient in the understanding of cylinder head configurations and gas flowing. In fact, Weslake had already done some considerable gas flow testing on earlier JAP speedway heads modified by an English engineer by the name of Don Godden. (That famous name will spur another chapter to come in this history). |
| That aside, Valentine felt he had something to offer the top end of the simple 500cc single cylinder speedway motor. |
| Opting to stick with the typical pushrod operated valvetrain, the super enthusiastic Valentine had the first Weslake speedway motor ready for competitive testing by September of 1974. The machine was first seen in public at Lydden and although did not finish the meeting (an electrical problem) it was obviously hugely more powerful than the 890 Jawa and it really caught some attention. |
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| My later model Weslake motor. Estimations put this example at around 1979-80. |
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| Don Godden (previously mentioned) already owned a successful speedway and grasstrack frame building company was desperately searching for a motor to fill his chassis. Ealier projects with JAP, Matchless and BSA had all failed due to the decline of the British Motorcycle Industry, and Jawa at that time cunningly refused to supply motors seperately. It was he and Dave Nourish who secured deals with the company as sole suppliers for the powerplant and with Valentine's hard work and continued dedication, the Weslake started to win everything. |
| Power was squeezed from everywhere, right down to the ignition being a seperate rechargeable battery system supplied by Interspan. As well as providing a more powerful spark than traditional systems, there is a theory that the power required to turn a magneto (the Jawa's ingnition system) is wasted energy. Therefore, the seperate battery box supplied both low and high tension power, with a simple trigger on the motor (contact breaker points) used to time the spark. Many top riders of today still opt for the Interspan system, believing this theory holds true, although nowdays the points have been replaced with Hall effect solid state electronic triggers. |
| The Jawa 890 all but disappeared from top flight speedway almost overnight and the Weslake domination was completed when Englishman, Peter Collins won the world individual speedway championship in 1976 aboard one. |
| There were to many more Weslake wins in various competitions, most noteably American Bruce Penhall's World titles in both '81 and '82. However, by then the Weslake did not have everything its own way. It continued to be the winningest engine but we were about to be entering the busiest period in speedway bike development history. |
| In 1978 Jawa, realising it had fallen behind, hurriedly released a four valve motor of its own. Also, having lost his Weslake deal in 1978 (Weslake chose to set up their own network of dealers and jacked their prices sky high), Don Godden was busy producing a motor of his own which would debut in 1979 and reach volume production for the 1980 season. |
| It is there I must end this episode of Speedway Bike History, 1960's to Present Day, however, on a personal note at the time of writing (Dec 2004) I have just come to own my very first Weslake. To me, the Weslake is the absolute speedway bike. I guess it all depends on what era one stems from, but as a child, peering through the wiremesh fence, looking down into the pits before the meeting, I have fond memories of car hoods up, Interspan's on charge and nearly every heat leader's bike being a Weslake. |
| To finaly own one, and to try to race it competitively all these years after their heyday, is a fitting segment in the twighlight of my speedway racing career, and life. |
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| My Weslake sports a British Antig chassis |
| with Brian sprung leading link front end |
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| THE COMPETITION HOTS UP! |
| As previously mentioned, the late seventies, early eighties were to be the busiest times to date for speedway bike development and number of suppliers. We have already documented in detail the enourmous success of the Weslake and we have mentioned the new offering from Jawa. With Don Godden's GR500 motor becoming increasingly popular, there was now a choice of three different complete speedway machines available for purchase. |
| Jawa's four valve offering, the 894 (an 895 variant was produced for longtrack) was an all new double overhead camshaft motor. Bulky and heavy and retaining a total loss lubrication system, it was never Jawa's best motor, however with the low overheads and labour rates of the former Eastern block Czechoslavakia working in its favour, it offered a slightly cheaper and perhaps more readily available option than it's British competition. With the volume production capabilities of the Jawa factory, and perhaps more importantly the widespread availability of spare parts, many Jawa 894's were sold. |
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| The Jawa 894 Motor |
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| The Weslake continued with good success through to about 1981, at which point the attention had shifted to the Godden GR500 as the "Best of British". Weslake's last real success came with Bruce Penhall's 1982 retention of his World Championship in the only World Final ever to be held in the USA. Interestingly, Les Collins, younger brother of the 1976 World Champion Peter Collins came a close second in that event. From then on, it became increasingly more difficult to remain competitive on the British Marque and production dwindled. The Weslake company made some vain attempts to produce both a single and a double overhead camshaft motor, but success never retuned to the organization to the degree it enjoyed in the mid Seventies. |
| The Godden, on the other hand was now proving itself as the fastest motor of the time, and coupled with the excellent pedigree of Don Godden's chassis was a hands down winning package. |
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| A Later Godden Machine |
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| Now, before our story takes us full thrust into the mid eighties we have to take a small step back. Although not to appear in any numbers for a few years, the birth of another brand of speedway motor had taken place in the unlikeliest of places in 1979. |
| An Italian speedway rider named Giuseppe Marzotto had already won his National Championship every year from 1975 to 1979. Origianlly mounted on Jawa but later switching to the superior Weslake machine, he was the undoubted No.1 rider in a country where speedway remains to this day very little known. |
| With no Weslake dealer any closer than Germany, Marzotto had terrible trouble obtaining the spare parts he needed to continue his racing at top National level. Perhaps only someone as brave (or perhaps as crazy) as a speedway rider would make the decision he was about to. He decided to overcome the problems of importing speedway equipment by building his own motor. He employed the services of an Italian engine designer named Giuliano Galiazzo and together they built the first prototype "GM" motor in 1979 (GM being the initials of Giuseppe Marzotto himself). |
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| THE NINETEEN EIGHTIES |
| The Godden and Jawa machines remained the hottest selling machines through until 1983, Weslake had disappeared and nothing had been heard of the GM. However, highly acclaimed engine tuner Otto Lantenhammer had been given a GM motor to "tweak" and he immediately saw huge potential in the Italian powerplant. So much so, he became the first ever official dealer for GM motors. This first production GM motor was known as the "SP". By 1983 he had squeezed enogh power from the GM SP to send German rider Gringo Brandt to the very top of the European grasstrack scene, and had been feverishly working on preparing a speedway motor for German Rider Egon Muller. |
| A fantasticly quick bike, and the huge longtrack experience of Muller was enough to win the 1983 World Speedway Final. The next season's 1984 World Championship Final win by Danish rider Erik Gunderson sealed an almost fairytale, metioric rise to fame for the Italian manufacturer. Everyone wanted a GM! |
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| Speedway Bike fitted with a GM SP Motor |
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| Jawa, realising that it's sales of the slow and dated 894 were slipping, released the single overhead camshaft 897 in 1984, one of the strongest motors produced by the Czech manufacturer to date in my opinion. |
| So we were back to three successful motor suppliers, two of which could provide a complete machine straight out of the crate. The GM motor had to be found a home in an "alien" chassis. Sales of the Italian engine were soaring, the lightweight Jawa 897 was finding many new fans and the Godden continued to improve, although perhaps still not being able to deliver in the quantities of it's competitors. |
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| Jawa 897 Motor |
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| It is also well worth a mention that at this point in history we were soon to witness the breaking of a long tradition of Speedway motor manufacture. Up to this point all speedway motors including the latest Jawa 897, all Weslakes, the Godden and the GM SP had used the "total loss" system. In other words, oil was fed to the motor from an oil tank (usually the frame tubes), pumped around the motor and then pumped out to a collection chamber behind the powerplant. This was then drained at regualar intervals to prevent overflowing. |
| This was seen as the best way to ensure the high standard of oil cleanliness required inside the often fragile and fast wearing speedway motor. |
| The next motors to be released by both Jawa and GM would have "re-circulating" oil systems. |
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| THE ARRIVAL OF THE "RE-CIRCS" |
| 1986 saw the release of the second generation GM motor, the LT. This was the first speedway motor with a re-circulating oil system. Modern technology, improved understanding of metallurgy resulting in better bearings and the introduction of a "Nickasil" or chromium plated cylider wall all combined to give the GM engineers the confidence to eliminate the need for total loss. |
| It was depicted that as long as the castor oil was changed once per meeting this would be sufficient to provide reasonable motor life. |
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| GM LT Motor |
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| Before we consign the excellent Godden to the speedway bike archives it is worth mentioning that although in limited numbers towards the very end of the nineteen eighties, they remained super-competitive. The superb and legendary Dane Hans Neilsen rode a derivitive of the Godden GR500 (called the Godden Max) to victory in the 1989 World Individual Final and in 1990 topped the British League riders averages with an outstanding 10.32. No one can claim the Godden faded away as a result of it's lack of speed. |
| However, with the sheer numbers of mass produced Jawas and the increasing poularity of the Italian GM, the Godden did just that. It faded away. The factory seemed unable to sustain a level of production necessary to make them count. It is still supposedly possible to order a new Godden Max powerplant, equipped for the modern laydown machine with re-circulating oil system et al. However, I doubt we will ever again see this remakable machine win top level speedway ever again. |
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| Entering the nineteen nineties, the only real players left in the speedway game were Jawa and GM. |
| With Jawa once again playing catchup, they released their first re-circulating oil machine in 1990. The model was named the 898 and was very similar to the very quick and strong 897, with the exception of the more modern appearence of the right hand timing cover. No longer requiring the external oil pump or the need for a chain to turn a magneto for the ignition system (a solid state electronic system was introduced on the 898) the motor looked much more like the motors we see today. |
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| Jawa 898 Motor |
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| Sucesses were shared by both manufacturers throughout the early nineties and both released newer versions of their motors. Firstly GM came out with the GM SRB8. I don't have the exact date of release but I'm going to speculate it was about 1993. Similarly, Jawa released their 884, a much improved motor on the old 898. Both of these motors were designed for vertical mounting in the frame. However, the single biggest change in speedway bike development was about to take place, and this would require both manufacturers to rethink a few things. |
