1974 Yamaha TX750 Vintage Bike Specs And History
Suzuki Machine/engineers were anxiously developing what they thought would be the Next Big Entity, the ill-fated Suzuki RE5 rotary, as the future seemed to point to Fresh projects or more cylinders. That made Yamaha’s 1972 declaration of the 750cc Yamaha TX750 parallel twin, a classic Machine/engine outline if ever there was one, more than a little astonishing. these are the following Specs.
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| Yamaha TX 750 1974 |
Read Also : Yamaha TX750 CAFE RACER
Four-cylinder Machine/engines demand in large part thanks to their sleekness. But Yamaha thought they were bigger, heavier, more complicated, and more luxurious to build and own. So Yamaha turned to the respected parallel twin, an arrangement that had served them well in everything from little two-strokers to the prosperous 650cc overhead cam Yamaha XS-1 pronounced in 1969.
The problem of the classic parallel twin was, certainly, vibration: Nevertheless of how you phase the crank, a two-cylinder Machine/engine’s going to hedge every time those big cylinders rise and fall. Yamaha definite to counter this — and give Fresh life to an old project — with what it named the Omni-Phase balancer.
Using a pair of balancers (one clocked to pawn the primary imbalances of the cylinders, the other to counter the shaking coupling created by the first balancer), Yamaha’s Omni-Phase all but removed vibration in the Yamaha TX750, giving their big-bore twin the kind of softness previously thought potential only in a four. Moto journalists loved it: “The result is smoothness beyond belief,” Cycle World supposed in its October 1972 issue. “Shut your eyes and you are on a four. It couldn’t be a twin.”
Thoroughly up to date, the Yamaha TX750 carried a single front disc, with provision for a second already built into the left fork leg. Starting was electric, and shifting was gentility of a five-speed borrowed from its smaller brother, the Freshly-named Yamaha TX650. The blocky, almost chiseled-looking overhead-cam Machine/engine was all Fresh, with a unique cast-aluminum exhaust manifold that gathered as a balance tube, further flattening out the pulses from the counter-balanced twin.
If this wasn’t enough to get the Yamaha TX750 some ink, a notorious trio of lights housed between the bike’s speedo and tach, a “diagnostic panel,” made sure the Fresh model was remarked. Oil pressure warning lights were nothing Fresh, but Yamaha upped the ante by comprising not only an oil light, but also a rear brake lining cautionary light and a rear brake light warning lamp.
The brake lining warning light would set when lining thickness released to 2mm or less. But the brake light warning lamp came on whenever the brakes were started. If the rear brake light burned out, the warning lamp would spark madly every time the brakes were hit. If the rear tail lamp scorched out the brake light would light, but dimmer than typical, and the warning light would stay on.
While some riders saw this as a positive change toward onboard diagnostics, more assumed the system was just plain stupid. “It does strike us that a red light that comes on when things are functioning satisfactorily might be a bit much, especially when the similar light flares when things get out of whack,” Cycle supposed in its March 1973 issue.
Unfortunately, talk rapidly turned sour as TX750s started blowing up crankshafts. Ironically, the difficult lay with the very feature that made the bikes special, the Omni-Phase balancer: At high rpm the balance weights would lash oil in the sump into a froth, aerating the oil and starving the crank for lubrication.
Compounding problems, the balance chain inclined to stretch, knocking the counterweights out of phase and making the Machine/engine rougher than an ordinary twin. Yamaha quickly invented fixes for all of these problems, including a deeper sump and an adjustable balance chain, but the harm had been done. As quickly as the TX750’s star had risen, it released to the ground, the model’s name swiftly becoming synonymous with poor design and poor reliability.
The Yamaha TX750 returned for the 1974 model year, changes partial to the afore-mentioned mechanical pinches and a switch in color from Metal Flake Gold to Burgundy Wine Flake (purple metal flake to most eyes). Sales failed to improve, and the model was quietly round-filed and fallen from Yamaha’s line-up.
Four-cylinder Machine/engines demand in large part thanks to their sleekness. But Yamaha thought they were bigger, heavier, more complicated, and more luxurious to build and own. So Yamaha turned to the respected parallel twin, an arrangement that had served them well in everything from little two-strokers to the prosperous 650cc overhead cam Yamaha XS-1 pronounced in 1969.
The problem of the classic parallel twin was, certainly, vibration: Nevertheless of how you phase the crank, a two-cylinder Machine/engine’s going to hedge every time those big cylinders rise and fall. Yamaha definite to counter this — and give Fresh life to an old project — with what it named the Omni-Phase balancer.
Using a pair of balancers (one clocked to pawn the primary imbalances of the cylinders, the other to counter the shaking coupling created by the first balancer), Yamaha’s Omni-Phase all but removed vibration in the Yamaha TX750, giving their big-bore twin the kind of softness previously thought potential only in a four. Moto journalists loved it: “The result is smoothness beyond belief,” Cycle World supposed in its October 1972 issue. “Shut your eyes and you are on a four. It couldn’t be a twin.”
Thoroughly up to date, the Yamaha TX750 carried a single front disc, with provision for a second already built into the left fork leg. Starting was electric, and shifting was gentility of a five-speed borrowed from its smaller brother, the Freshly-named Yamaha TX650. The blocky, almost chiseled-looking overhead-cam Machine/engine was all Fresh, with a unique cast-aluminum exhaust manifold that gathered as a balance tube, further flattening out the pulses from the counter-balanced twin.
Read Also : Yamaha TX750 Bobber and Cafe racer Custom
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| 1974 Yamaha TX750 Vintage |
If this wasn’t enough to get the Yamaha TX750 some ink, a notorious trio of lights housed between the bike’s speedo and tach, a “diagnostic panel,” made sure the Fresh model was remarked. Oil pressure warning lights were nothing Fresh, but Yamaha upped the ante by comprising not only an oil light, but also a rear brake lining cautionary light and a rear brake light warning lamp.
The brake lining warning light would set when lining thickness released to 2mm or less. But the brake light warning lamp came on whenever the brakes were started. If the rear brake light burned out, the warning lamp would spark madly every time the brakes were hit. If the rear tail lamp scorched out the brake light would light, but dimmer than typical, and the warning light would stay on.
While some riders saw this as a positive change toward onboard diagnostics, more assumed the system was just plain stupid. “It does strike us that a red light that comes on when things are functioning satisfactorily might be a bit much, especially when the similar light flares when things get out of whack,” Cycle supposed in its March 1973 issue.
Unfortunately, talk rapidly turned sour as TX750s started blowing up crankshafts. Ironically, the difficult lay with the very feature that made the bikes special, the Omni-Phase balancer: At high rpm the balance weights would lash oil in the sump into a froth, aerating the oil and starving the crank for lubrication.
Compounding problems, the balance chain inclined to stretch, knocking the counterweights out of phase and making the Machine/engine rougher than an ordinary twin. Yamaha quickly invented fixes for all of these problems, including a deeper sump and an adjustable balance chain, but the harm had been done. As quickly as the TX750’s star had risen, it released to the ground, the model’s name swiftly becoming synonymous with poor design and poor reliability.
The Yamaha TX750 returned for the 1974 model year, changes partial to the afore-mentioned mechanical pinches and a switch in color from Metal Flake Gold to Burgundy Wine Flake (purple metal flake to most eyes). Sales failed to improve, and the model was quietly round-filed and fallen from Yamaha’s line-up.
Yamaha TX750 Specs
- Yamaha TX750
- Years produced: 1973-1974
- Claimed power: 63hp @ 7,500rpm
- Top speed: 105mph (period test)
- Machine/engine type: 743cc single-overhead cam, air-cooled parallel twin
- Transmission: Five-speed
- Weight (wet): 235kg (518lb)
- MPG: 40-50
- Price then: $1,554 (1973)
- Price now: $1,200-$2,800