Something special
Making Yamaha's ‘everyman' trials bike into a superstar took the talents of a dedicated team.
Yamaha produced thousands of TY models – good as they were, they could be even better.
In the same way British trials machines reflected a company's roadster range and were a tool to sell road machines, so the Japanese industry was interested in volume sales too. Stand a typical 350/500 four-stroke single comp bike next to its stablemate roadster and the similarity is obvious, the comp model may have smaller fuel and oil tanks, blade type mudguards and so on, but the heritage is clear. Their works riders would be seen to be winning on what was being sold and woe betide any rider who dare demand something a little more special.
By the time any of the Japanese factories took an interest in this trials thing the scene had changed. British factories were gone, their star riders available to help the Oriental designers and engineers understand what was needed for success in the feet-up game. The Japanese industry had an advantage or two over British factories, first of all they were selling thousands of tiny machines to Asian countries and income from such sales allowed the factories to experiment, and competition department budgets are the stuff of legend. These newcomers were also unfettered by the need to have their star riders on production based machines, as long as the logo on the tank was the same as the logo on the volume selling machines then all was okay.
There also seemed a need to experiment with things and an attitude of ‘well, let's see if we can…' was prevalent. There was no hesitation in trying something, finding it didn't work and moving on, and in a chat with AMC, OSSA and Yamaha star Mick Andrews a while ago, he related tales of things arriving from Japan, to be fitted to his machine, tried, then removed and sent back for evaluation. When Andrews went to Yamaha he turned out on what seemed a new machine every trial, bigger, smaller, cantilever, twinshock and so on. What the factory were doing was understanding what went on in a particular sport, the ideas tried would be filed away for future use and when Mick won the SSDT in the mid1970s on a bike with cantilever, or monoshock if you prefer, suspension, it was best part of 10 years later a production machine so equipped arrived on the scene.
Before then the company introduced a trials machine which had similarities to the other dirt bikes in their range but was essentially all new. Mick had launched this attractive light grey and yellow machine at British trials and it proved a worthy performer, typically of the Japanese industry it was available with full road equipment and harked back to the era when an owner rode on Sunday and went to work on the bike on Monday even though this era had long gone. Many of these TY – Trials Yamaha perhaps – models would have seen duty as easy to ride trail machines even though there were other models in Yamaha's ranges which were for trail riding.
Contemporary reports suggested the new TY250A was an excellent machine and Yamaha did develop the bike over the next few seasons but essentially the basic model remained all one could buy if Yamaha was your thing. The problem was trials was now a rapidly changing sport and what suited in 1974 was not so suitable as 1980 approached. The dilemma for Japanese factories was profitability lay in selling lots of a model but the nature of the sport meant a machine was quickly outdated and needed to change rapidly.
Into this climate came the smaller, almost dealership, concerns, that without the necessity of making large quantities were able to modify and
There also seemed a need to experiment with things and an attitude of ‘well, let's see if we can…' was prevalent.
alter a stock machine using as many of the standard components as possible. Yamaha's TY engine unit was a tough thing with an inbuilt reliability and could easily be upgraded to match the opposition machines. Its problem was the chassis had become outdated and was preventing the engine from being as good as it could be. Effectively the frame was too low, giving away quite a bit of ground clearance to the opposition.
Mick Andrews was still winning trials on Yamahas but the heady days of ‘what's he going to be on this week?' had gone, as had the super trick bikes he'd been riding, and it is no great secret Yamaha management would turn up at the Andrews' workshop in Derbyshire, instruct Mick to destroy the machine he'd been riding, remove the headstock and engine case with chassis and engine numbers on, then and only then would his next machine be handed over.
It seemed as though trials were on the back-burner at Yamaha, but there were still lots of the tough 250 TYS about. Mick had been experimenting with various modifications to standard machines himself and a collaborator in this was John Shirt, the pair went the whole hog and produced an uprated machine handbuilt in the style of factory machines. Choosing a name for this special Yamaha couldn't really have been any simpler: with Mick Andrews' (MA) and John Shirt's (JES) initials added to the Yamaha model designation (TY), this king of trials motorcycles suits its regal title of MAJESTY.
An advantage in a project such as this is the number of standard components which can be used, modified perhaps but still useable. Initial development centred on using Yamaha's standard frame and lifting the engine up in it, this was followed by chopping the frame tubes off under the engine before fitting a flat alloy sump shield. Initially modifying all standard components it soon became clear a purpose-made frame was needed to capitalise on the work done to engines. So when the idea of their own frame came to fruition – actually frames were made by Don Godden the grass and long track racer – it used Yamaha forks, wheels, exhaust and so on.
Topping off the new machine was a superb example of the panel beater's art in the alloy petrol tank. Right from the start of production the Majesty could be tailored to a rider's requirements and the sort of rider who would be purchasing one is likely to have a decent idea of the requirements to have it tailored to.
According to the adverts in the press, each frame built by Don Godden was crafted from TIG welded aircraft specification tubing which had been certified by x-ray inspection for integrity. It was claimed TIG welding was the best type of welding as it beats any distortion in the welding process.
Furthermore each engine was stripped and rebuilt with the knowledge gleaned from working with them – porting was changed, cylinder head work was done and when assembled the carburation was changed
and matched to revised ignition settings to give a motor with power more suitable to the trials it would encounter at the end of the decade rather than those of when it was conceived.
There followed a further claim each machine was meticulously assembled by hand, with much attention to detail and effectively the type of attention given to works machines.
As there was a move to bigger engines in the late Seventies – Bultaco had their 325 and would be working on their 340 – Montesa had produced the 310 and were working on a version nearer to 350cc, so the Majesty concern looked at a bigger motor and came up with a 320 capacity and in this form was ridden by Mick Andrews to win a world championship round, something not to be sniffed at under any circumstances. Though of very low production numbers, the Majesty in whichever capacity you fancy, is a highly desirable machine which exudes quality – but this high quality is one of the reasons why it is rare as it takes time to build such machines.
Being hand-built to exacting standards these machines are ideal for modern twinshock trials but their rarity means getting hold of one isn't easy. The situation was eased a little when Mick Andrews was allowed to produce a batch of six frames from the drawings of his old works machines and this particular one headed for Mike Ernst in Germany.
Mike is a keen trials and enduro rider with a soft spot for the Yamaha machines, and felt a 320 Majesty was needed in his life. On the day we photographed his newly-built machine just before the Manx two day trial he told us it was the first trial the bike had been in and the frame was number three from the batch built.
Due to various marketing rights and restrictions, the frames are labelled MATY rather than MAJESTY but officially sanctioned nonetheless. Fitted to the front end are standard Yamaha fork yokes and what look like standard Yamaha TY forks, but aren't. There has been a world of development with suspension at either end of a motorcycle and the internals of these forks reflect these developments and are to ‘works' standard. What this means is very careful assembly and attention is paid to the oil control holes to ensure both legs are matched evenly. This done, and fork springs fitted to suit the bike and Mike's riding weight, suspension is very good indeed.
Also with springs and damping matched to the rider and bike are Falcon shocks on the rear. These particular shocks were sourced via a Manx friend of Mike's. In the day, Japanese brakes were reckoned to be the best available and their labyrinth seals kept water and muck out of the braking area which is why the original hubs are reused. Laced on to new alloy rims with stainless steel spokes and IRC tubed tyres in place has the rolling chassis sorted out.
The engine is a little more complex to deal with and some serious work has gone on to increase
the capacity. First task was to alter the crankcases to accept the slightly wider barrel needed for the 320. “I was lucky there as I managed to get hold of a genuine 320 barrel and Neil Walker matched it to the cases for me,” says Mike.
A barrel needs a piston inside it and one from the DT360 Yamaha fitted the bill nicely, though a spacer was needed to lift the barrel up a bit. The bigger barrel needed a different inlet tract in order to mate up the carburettor and while Yamaha in manufacture the new inlet certainly isn't TY or DT, but originates on the RD400 two-stroke twin.
Why use an RD400 one Mike? “The roadster inlet tracts are straight and that's what we needed,” he says. A rejetted Mikuni carburettor sits on the end of the inlet and on the other side of the carb is a much bigger than standard airbox to help the bigger engine breathe. “We made the airbox at home,” says Mike, unintentionally confirming the network of supply is as common in Germany as in the UK.
Getting the fuel inside the combustion chamber is only part of the story of course and there needs to be a spark to ignite it. This comes via an ignition from John Cane at Trail and Trials.
Once the engine was in the frame an exhaust could be offered up, a standard one fits but needed shortening by about 40mm then on the end sits a WES alloy silencer. These are repackable and as such helps to keep a two-stroke in proper tune. Despite all these modifications the rest of the base motor is fairly typical TY250, it has five speeds, has a gear primary drive and can be started in gear.
We've pointed out there are a lot of standard or stock parts on this Yamaha however, there are a number of things non-standard or specific to a Majesty and one of the most striking is the petrol tank, to call it just an alloy tank is to ignore the skill in making such a sensuous petrol container… yeah I like it.
Through Mike's business he makes bar pads, bike covers and lever covers, and the 320 wears a few of his products and they finish off the bike nicely.