1973 Honda Bials TL125 – Classic Trial Motorcycle Specs, Pictures
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| Honda Bials TL125 photo. 1st Generation. model year 1973 |
Honda Bials TL125 is Japan’s first full-fledged trials machine and at the same time suitable for driving on general roads. Equipped with an air-cooled 4-stroke single-cylinder engine with a displacement of 122cc, it was given tenacious output characteristics for trial runs where extremely low speeds were often used. The specifications for trial driving also affected the gear ratio of the 5-speed return transmission, and the 1st to 3rd gears were for trials, and the 4th to 5th gears were for transportation.
The Bials TL125 was a trial bike that was released in January 1973 and could be ridden on public roads. The name BIALS itself is a coined word meaning “BIKE suitable for trial races”. In addition, “Trials” is the term used to refer to motorcycle games (and competitions) that involve running through complex terrain with steep slopes and large irregularities, such as rocky areas and mountain roads, but in the 1970s, the correct name was “Trials”.
1973 Honda Bials TL125 Features
- It has all the functions that can be used for trial driving.
- It is a sports car that can be enjoyed not only off-the-road driving, but also on ordinary roads.
- A 4-cycle OHC single-cylinder 122cc engine with a particular focus on low-speed stickiness.
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| Picture of Honda Bials TL125 1973. ホンダ バイアルス TL125. Body color: white. |
Release date : January 30, 1973.
BIALS = BIKE + TRIALS, from the meaning of BIKE suitable for trial riding.
Honda Bials TL125 Price in 1973 was : 152,000 yen (national standard cash price).
Production Plan was 2,500 monthly production (including export) in the year of 1973.
1973 Honda Bials TL125 Basic Specs
| Type grade name | BIALS TL125 |
|---|---|
| Model change classification | New release |
| Model | TL125 |
| Release year | 1973 |
| Launch month | 1 |
| Destination/specification | Domestic model |
| Total length (mm) | 1995 |
| Width (mm) | 840 |
| Total height (mm) | 1095 |
| Wheelbase (mm) | 1280 |
| Minimum ground clearance (mm) | 260 |
| Dry weight (kg) | 98 |
| Minimum turning radius (m) | 1.8 |
| Riding capacity (person) | 1 |
| Motor model | TL125E |
| Motor type | 4-stroke |
| Number of cylinders | 1 |
| Cylinder arrangement | Single cylinder |
| Cooling method | Air cooling |
| Displacement (cc) | 122 |
| Cam valve drive system | OHC (SOHC) |
| Number of valves per cylinder | 2 |
| Cylinder bore (mm) | 56 |
| Piston stroke (mm) | 49.5 |
| Compression ratio ( :1) | 8 |
| Max Power (PS) | 8 |
| Max output speed (rpm) | 8000 |
| Maximum torque (kgf･m) | 0.83 |
| Maximum Torque Speed (rpm) | 4000 |
| Fuel supply system | Carburetor |
| Fuel tank capacity (L) | 4 |
| Engine starting method | Kick starter |
| Ignition | Magnetic |
| Battery/model | 6N2-2A |
| Battery capacity | 6V- 6Ah |
| Engine oil capacity*Total capacity (L) | 1.0 |
| Clutch type | Wet type, multi-plate |
| Transmission type | Return type, 5-speed transmission |
| Transmission and operation method | Foot shift |
| Primary reduction ratio | 4.055 |
| Secondary reduction ratio | 4.000 |
| Transmission ratio | 1st gear 2.769 2nd gear 2.125 3rd gear 1.577 4th gear 1.000 5th gear 0.723 |
| Power transmission system | Chain |
| Chain size | 428 |
| Standard number of chain links | 120 |
| Frame type | Semi-double cradle |
| Caster angle | 61°30′ |
| Trail amount (mm) | 105 |
| Brake type (front) | Mechanical leading trailing |
| Rake type (rear) | Mechanical leading trailing |
| Suspension system (front) | Telescopic fork |
| Front fork type | Upright fork |
| Suspension system (rear) | Swing arm Formula |
| Number of shock absorbers (rear) | 2 |
| Tires (front) | 2.75-21 |
| Tire (front) construction name | Bias |
| Tire (Front) Ply Rating | 4PR |
| Tire (Front) Type | Tube Tire |
| Tire (rear) | 4.00-18 |
| Tire (rear) construction name | Bias |
| Tire (rear) ply rating | 4PR |
| Tire (rear) type | Tube tire |
| Wheel rim width (front) | 1.4 |
| Wheel rim width (rear) | 2.15 |
| Tire standard specified air pressure (at passenger capacity/before) | 1.50 |
| Tire standard specified air pressure (at passenger capacity/after) | 1.50 |
| Headlight rating (Hi) | 25W/25W |
| Tail light rating (braking/tail light) | 10W/3W |
| Speedometer display format | Analog |
1975 Honda BIALS TL125 Specifications
In 1975, Honda Bials underwent minor changes. As for the “Bialus” series, the competition model Bials TL250 (1975) and the moped class Bials TL50 (1976) were lined up.
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| Honda Bials TL125 model year 1975 with a little bigger engine displacement and double rearview mirror. |
The engine displacement is 124cc. The gear ratio of the 3rd gear has been changed, and it can now be used in a form that connects 1st to 2nd gear and 4th to 5th gear. The fuel tank capacity has been changed from 4 liters to 4.5 liters.
Here the full specs of Honda Bials TL125 model year 1975:
| Type grade name | BIALS TL125 |
|---|---|
| Model change classification | Minor change |
| Model | TL125S |
| Release year | 1975 |
| Launch month | 7 |
| Destination/Specifications | Domestic For models |
| Overall length (mm) | 1995 |
| Overall width (mm) | 840 |
| Total height (mm) | 1095 |
| Wheelbase (mm) | 1280 |
| Minimum ground clearance (mm) | 220 |
| Dry Weight (kg) | 98 |
| Minimum turning radius (m) | 1.8 |
| Riding capacity (name) | 1 |
| Motor model | TL125SE |
| Motor type | 4-stroke |
| Number of cylinders | 1 |
| Cylinder arrangement | Single cylinder |
| Cooling method | Air cooling |
| Displacement (cc) | 124 |
| Cam valve drive system | OHC (SOHC) |
| Number of valves per cylinder | 2 |
| Inner diameter (cylinder bore) (mm) | 56.5 |
| Piston stroke (mm) | 49.5 |
| Compression ratio | 8:1 |
| Top Power (PS) | 8 |
| Max output speed (rpm) | 8000 |
| Maximum torque (kgf･m) | 0.83 |
| Maximum torque speed (rpm) | 4000 |
| Fuel supply system | Carburetor |
| Fuel tank capacity (L) | 4.5 |
| Engine starting method | Kick starter |
| Ignition device | Magnet type |
| Equipped battery/model | 6N2-2A |
| Battery capacity | 6V-6Ah |
| Engine oil capacity*Total capacity (L) | 1.0 |
| Clutch type | Wet, multi-plate |
| Transmission type | Return type, 5-speed |
| Transmission and operation method | Foot shift |
| Primary reduction ratio | 4.055 |
| Secondary reduction ratio | 4.000 |
| Transmission ratio | 1 Speed 2.769 2nd speed 2.125 3rd speed 1.450 4th speed 1.000 5th speed 0.723 |
| Power transmission system | Chain |
| Frame type | Semi-double cradle |
| Caster angle | 61°30′ |
| Trail amount (mm) | 105 |
| Brake type (front) | Mechanical Leading trailing |
| Brake type (rear) | Mechanical leading trailing |
| Suspension system (before) | Telescopic fork |
| Front fork type | Upright fork |
| Suspension system (rear) | Swing arm type |
| Number of shock absorbers (rear) | 2 |
| Tire (front) | 2.75-21 |
| Tire (front) construction name | Bias |
| Tire (front) ply rating | 4PR |
| Tire (front) type | Tube tire |
| Tire (rear) | 4.00-18 |
| Tire (rear) construction name | Bias |
| Tire (rear) ply rating | 4PR |
| Tire (rear) Type | Tube tire |
| Wheel rim width (front) | 1.4 |
| Wheel rim width (rear) | 2.15 |
| Tire standard specified air pressure (at passenger capacity/front) | 1.50 |
| Standard specified tire pressure (at passenger capacity/after) | 1.50 |
| Headlight rating (Hi) | 25W/25W |
| Tail light rating (braking/tail light) | 10W/3W |
| Speedometer display format | Analog |
Check also the successor, Honda Ihatovo TL125S model year 1981.