On the move: Yamaha TX 750

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On the move: Yamaha TX 750
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On the move: Yamaha TX 750

A model chronicle of the Yamaha TX 750

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With innovative technology and impressive characteristics, the Yamaha TX 750 made its debut in the trade press in 1972/1973. After only two years she disappeared into oblivion. Today it is considered a rarity that is cherished and looked after by its owners.

It just wasn’t meant to be. First, the trade press praised it for its great engine with the ingenious balance shaft system – for the first time ever in motorcycle construction, the vibrations were eliminated by balance shafts. Then the crash followed as the full extent of the technical problems became apparent. In 1973, when sales of the TX 750 had just started, Yamaha initiated the first aid measures. Employees were sent to dealers across Germany to retrofit oil coolers on new vehicles. It must have looked desperate. And they could no longer save their image, which was already scratched at this point.

S.o Like the TX shown here, today you hardly ever come across machines without an oil cooler. Many owners have even developed their own solutions to tackle temperature problems. The interference tube on the cylinder head was considered the main culprit from the start, but it could not be easily removed. There were other places that hobbyists tinkered with. For example on the oil filter hidden behind the pinion cover. A misshapen cartridge that is flanged to the gear housing like a tinny ulcer with two oil lines. TX drivers were concerned that the glue in the filter cartridge could dissolve, clog oil lines and lead to major engine damage. The expensive part was quickly dismantled and an aluminum cover was made to fit as an adapter piece.

Instead of the externally flanged cartridge, an inexpensive filter from the Honda FT 500 or the BMW R 65 fits directly into the engine housing, with the lid on, and that’s good. Others led the oil lines straight to the front and installed a car oil filter cartridge in front of the crankcase in the cooling airstream. In addition, they cut out the air scoop indicated in the right side cover so that the airflow could fan cooling air to the oil tank behind it. After all, the TX already has air slots in the generator cover ex works, so warm exhaust air can escape to the rear. The starter was also gladly sacrificed. The starter mechanism with its drive chain was considered prone to failure anyway, and a kick starter was enough.


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The speedometer of the Yamaha TX 750.

In addition to the technically complex engine, Yamaha also installed interesting gadgets in the cockpit: three inconspicuous red indicator lights. On the left the oil pressure control. The “Brake Lamp” in the middle lights up when the rear brake pads are worn out, and the “Tail Lamp” warns of a defective rear light. If the dipped headlight filament burns out, an auxiliary light relay automatically switches to high beam. Yamaha demonstrated far-sightedness with these gadgets that were already functioning at the time.

And there are owners who just drive their TX. Like Hans Hartmann from Krefeld, who bought a new TX 750 in 1973 and has covered around 85,000 kilometers on it to date. Hartmann is one of the contacts for the 1984 founded "IG Yamaha TX 750". This takes care of the preservation of the now rare parallel twin and is at the side of other TX drivers with advice and action. For example, at the annual TX meeting from June 17 to 19, 2011 or by phone on 0 21 51/30 54 15 (private) or 0 21 62/39 12 93 (office). www.tx750.de

The history of the Yamaha TX 750


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The back of the Yamaha TX 750 with drum brake and the characteristic rear light.

Yamaha’s success story is based on motorcycles with two-stroke engines, at least until 1970. When the Honda CB 750 Four, BMW R 75/5, Suzuki GT 750, Kawasaki 750 H2 and other powerful machines entered the stage in the late 1960s and early 1970s, The Japanese manufacturer is under pressure to develop a competitive big bike. Its first four-stroke model, the XS 650, which was offered in Germany in 1971 and 1972 under the name XS 2, sells moderately, a four-cylinder two-stroke model with 750 cc and the name GL 750 was rejected by Yamaha shortly after its introduction. The decision was made again in favor of a four-stroke engine, although the company had no success with the XS 2. A newly designed large parallel twin is to replace this. But even before marketing strategists in the Far East think about the European market, the Yamaha TX 750 finds its way into the trade press.

In the 12/1972 issue of Das MOTORRAD it captivates the viewer on the back cover page, in large format and in color. The editorial staff blaspheme about the fact that Yamaha is only selling “this beautiful 750 four-stroke with 63 hp” in Japan and that the “old 35 hp 650” should continue to come to Europe. Yamaha sold just 350 of the XS 2 machines in Germany until 1972 before the importer took them out of the range.

The sting sits. Ernst writes seven issues later "glob" Leverkus of a reply from the manufacturer. In spite of the prophecies of doom, the 750 with the newly designed four-stroke parallel twin should come to Europe, but the Japanese are silent about the timing. Shortly afterwards, Mitsui Maschinen GmbH from Meerbusch, at that time the general importer of the Yamaha brand in Germany, announced the market launch of the TX 750 for 1973.

Now things are moving and only a little later the editorial team in Stuttgart receives an unexpected call inviting them to drive the prototype in Dusseldorf. A Japanese team is on the road with a pre-production model on European roads to test the machine under local conditions. The editors can get their first impressions of the prototype under the watchful eyes of the testers. And the Japanese are hoping for their last tips to adapt the sporty twin to European road conditions. You are under a lot of pressure, want to meet all requirements and do better this time. The debacle with the XS 2 is still on their necks. The editors’ rapture over the first driving impressions knows no bounds: "The acceleration in the III. and IV. gear is enormous and we were completely enthusiastic, unfortunately there was no time for precise measurements", confesses no brainer.


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The four-stroke parallel tiwn from Yamaha, first introduced in Germany in 1973.

Two months later, the back of Das MOTORRAD 2/1973 features a four-color glossy advertisement from the "Queen of the Road" and dispels any last doubts about their launch. It should be at the dealerships in February. In the winter of 1972/73, the TÜV inspected the machine and editors were given another opportunity to test it. In issue 5/1973, Klacks reported in detail about his driving impressions. He notices that of the targeted 63 hp with the sound absorption permitted for Germany, only 51 hp at 7000 rpm remain. This would mean that the performance would still be within the scope of the current 750 class, "so that Yamaha doesn’t have to hide with it."

His verdict on the machine is consistently positive, he praises yours "soft, cultivated and powerful sports engine" and also the stiff chassis and hers "excellent double disc brake". Despite the very high weight, it is very handy and lively. "It is a direct competitor to the English two-cylinder machines and should be taken very seriously in this role." No brainer notes "Firstly, that the engine pulls through very nicely from below, secondly, that it runs smoothly and without vibrations, and thirdly, it is easy to turn."

All in all, that sounds promising. The low-vibration running of the engine is particularly impressive – some even compare it to the smoothness of a four-cylinder. Yamaha elegantly eliminates the vibrations of the twin with two balancer shafts – a novelty in motorcycle construction. Klacks only speaks with skepticism about the piston speed: it reaches 17.3 m / s at a nominal speed of 7000 / min and almost 20 m / s at 8000 / min. At maximum speed on the motorway and 9000 rpm, the pistons move up and down at 22 m / s, he calculates. Meanwhile, Yamaha is launching an advertising campaign for its new model range and is placing a full-page TX 750 ad with the title in issue 5/1973 "Ride the bull".

In the following issue, Das MOTORRAD presents the cut parallel twin in large format on the inside back cover. The figure clearly shows the valve control of the four-stroke engine and the two weights of the chain-driven balance shafts below the gearbox – from Yamaha as "Omni-phase balancer system" designated.


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Only present on the front wheel of the Yamaha TX 750: the disc brake.

The technical effort to effectively prevent engine vibrations on the TX is the reason for the editorial team to give a detailed report on the origins of engine vibrations and vibrations in issue 15 and 16/1973 of Das MOTORRAD and to show the manufacturers’ various solutions. The method of uncoupling the engine blocks from the frame with rubber elements was widespread at the time, with mostly modest success. And some English twins also shook the last crown out of their driver’s teeth.

1973 dealers in Germany sell around 700 copies of the TX 750. While in America, which is limited in speed, hardly anything can be heard about problems with the parallel twin, the owners in Europe do not just break out in praise. Soon they complain of major engine damage, leaked bearings, gearbox problems and more. This puts the manufacturer’s goodwill to a serious test. Yamaha takes on the complaints and practices generous courtesy. In the meantime, engineers are feverishly looking for the causes and implementing a number of improvement measures. The third generation of the parallel twin alone has to endure 18 serious engine changes. Among other things, it receives a camshaft with tamer valve timing, modified connecting rod bolts and a new cylinder head gasket. The factory had already fitted the machines with oil coolers and an oil pan spacer ring for a larger volume of lubricant. These measures should help to get the dangerously high oil temperatures under control that can occur during long, fast cross-country journeys.

All the measures introduced by Yamaha to make the TX operational and suitable for everyday use can no longer win back the trust of buyers. Neither have the hymns of praise in the trade press: The MOTORRAD judges in its with "Passed the maturity test" titled report in issue 13/1974 the machine was very positive and praised its properties: "For the beautiful hobby of motorcycling, models will have to be available in the future that move unobtrusively on their way. And the Yamaha TX 750 meets these expectations."


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The readers of Das MOTORRAD saw the Yamaha TX 750 for the first time in issue 12/1972. The sunrise soon became set.

But their reputation is already ruined. And who wants to "unobtrusively move its path"? Editor Ilse Reuter as a dashing cover girl does not increase sales figures either. Other manufacturers have much more exciting motorcycle models in their range that are also less vulnerable than the Yamaha. In 1974, 600 machines found a buyer in Germany, a year later they disappeared from the dealers’ showrooms and sales brochures.

Rodney Gould, 1970 world champion on a 250cc Yamaha and subsequently PR manager for the brand, told the media at the time: "We wanted to prove that you can also build a large-volume two-cylinder that runs with little vibration." At least that’s what they did impressively with their second four-stroke model.

Finally, Yamaha is dedicating itself again to the British-influenced XS 2, with which it began its four-stroke career. In 1975 it came onto the market in a revised form as the XS 650 B. The decision to step back turns out to be a leap forward. The XS 650 becomes a bestseller and is in the range until 1984 – even without vibration-eliminating balance shafts.

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