Component of motorized two-wheelers
1968 BMW R60US with conventional telescopic forks Unusual "rear lower link" on a Honda Rune
Motorcycle fork
connects the motorcycle's front wheel and axle to its frame, usually using a clamp, also known as a triple clamp, which consists of an upper yoke connected to a lower yoke by a steering rod, a shaft that passes through the steering head, creating the steering axis. Most forks include front suspension and a front brake and allow the front wheel to rotate around the steering axis so the bike can be steered. Most handlebars attach to the top clamp in a variety of ways, while snap handlebars attach to the fork tubes just above or just below the top triple clamp.
The fork and its mounting points on the frame determine critical geometry parameters of rake and trail, which play a major role in determining how the motorcycle handles and pitches during braking. [1] While the standard telescopic fork arrangement has been standard with little significant variation among conventional street motorcycles since the 1970s, historically there have been many variations, including trailing or live link, coil spring, Earls, beam and others, as well as non being steering forks such as hub-center steering.
Options [edit]
Over the course of more than a hundred years of motorcycle development, various fork arrangements have been tried, some of which are still available today.
Telescopic[edit]
Main article: Telescopic fork
BMW version of the oil-damped telescopic fork on the 1939 R12
In a telescopic fork
Fork tubes are used, inside which are the suspension components (coil springs and damper). This is the most common plug shape available in the market. It may or may not include gaiters to protect against abrasive elements on the suspension cylinders. The main advantages of a telescopic fork are that: (i) it is simple in design and relatively cheap to manufacture and assemble; (ii) it is lighter than older designs using external components and clutch systems; and (iii) it has a clean and simple look that appeals to bikers.
Typically the fork legs are at the top, secured by the fork (also called a triple tree or triple clamp), and the sliders are at the bottom, attached to the front wheel spindle. On some modern sportbikes and most off-road motorcycles this system is inverted, with the "sliders" (complete with spring/damper) at the top attached to the fork and the struts at the bottom. This is done (i) to reduce unsprung mass by suspending heavier components and (ii) to increase the strength and rigidity of the assembly by having strong, large diameter "sliders" clamped into yokes. [2] An inverted system is called an inverted fork.
, or "US dollar" for short. The disadvantage of this USD design is that the entire reservoir of damping oil is located above the slider seal, so if the slider seal leaked, the oil could drain, rendering any damping ineffective.
End link[edit]
Trailing arm fork on a 1928 Indian Big Chief
A trailing link fork suspends the wheel on a link (or links) with a pivot point forward of the wheel axle. The most widely used is Indian Motocycle; it was also used by BMW for its early motorcycles.
Lead link[edit]
Ural version of the front lever fork
The drive link fork suspends the wheel on a link (or links) with a pivot point behind the wheel axle. On Russian Ural motorcycles, live-link forks were used on motorcycles with sidecars, and aftermarket live-link forks today are often installed on motorcycles when equipped with a sidecar. They are also very popular among motorcycles, improving handling when steering or braking. The most common example of a front link fork is the Honda Super Cub fork.
Springer[edit]
Early Harley-Davidson with spring fork
Springer forks
early type of leading line fork. The spring fork does not have suspension built into the fork tubes, but is instead mounted externally where it can be integrated into a triple clamp. This fork style can be found on vintage motorcycles or choppers, and is available today on the Harley-Davidson Softail Springer.
Although it may have an exposed spring next to the triple clamp, a spring fork is distinguished from a beam fork by having two parallel sets of legs. The back is rigidly attached to the lower triple clamp (usually soldered or welded). A short drive link holds the wheel and the front leg, which operates the springs (usually mounted on a triple clamp).
Earls[edit]
Earles fork on a 1952 Douglas Dragonfly.
Earles forks
is a type of fork drive link where the pivot point is behind the front wheel, which is the basis of the Earles patent. [3] The design, patented by Englishman Ernest Earls in 1953, consists of lightweight tubes with conventional "shock absorbers" mounted next to the front axle. The Earles fork has very little change in wheelbase under braking or compression, unlike a telescopic fork. Their design is much stronger than telescopic forks, especially against lateral deflection caused by sharp turns (such as during racing) or when turning with a sidecar. [3] This triangular fork causes the front of the motorcycle to lift slightly under heavy braking as the mechanical braking forces rotate "down" relative to the fork's pivot point. This action can be confusing for drivers accustomed to telescopic forks, which have the opposite response to braking force ("dive when braking"). Several motorcycle manufacturers licensed Earles patent forks for racing motorcycles in 1953, such as MV Agusta and BMW Motorcycle, while other companies (such as Douglas Motorcycle) used the Earles design on their roadsters or off-road vehicles. BMW used Earles forks on all of its motorcycles between 1955 and 1968.
Beam [edit]
| This section may require cleaning to meet Wikipedia quality standards. |
1934 Cotton with beam fork
A beam fork, one of the earliest types of motorcycle front suspension, consists of a pair of struts attached to a triple clamp by spring-loaded arms, usually between the upper and lower triple clamps. The design reached its peak with the "Girdraulics" used on the Vincent motorcycle. Girdraulic forks feature forged alloy blades for added strength and hydraulic damping. [4]
While both may have an exposed spring near the triple clamp, a beam fork differs from a spring fork in that the wheel is rigidly mounted to a (usually long, diamond-shaped) upright post. The pivot points are short links attached to the top and bottom triple clamps. The spring is usually attached to the beam and pressed against the top triple clamp.
Although beam forks are associated with early motorcycles, the British Ariel Ace, a modern sports motorcycle, has an alloy space frame and matching beam fork. This Ariel beam fork is just as susceptible to drag as any telescopic fork, but is said to be more resistant to twisting.
Saxon-Motodd (Telelever) [edit]
Telelever fork on BMW R1150R
Saxon-Motodd (sold as Telelever
on BMW) has a wishbone that attaches to the frame and supports the monoshock absorber unit. This relieves the fork of braking and suspension forces. With Telelever, the backrest and caster angles (rake) increase during braking, rather than decreasing as with traditional telescopic forks. [5] BMW's boxer twins have been equipped with Telelever forks since 1994, but some new boxers, such as the BMW R nineT, have reverted to conventional telescopic forks for aesthetic and packaging reasons.
Hossack/Fiore (Duolever) [edit]
Duolever front fork
Hossack/Fiore (marketed as Duolever
from BMW) completely separates the suspension from the steering effort. Developed by Norman Hossack [6] and used by Claude Fiore and John Britten on racing bicycles, Hossack described the system as "vertically controlled". In 2004, BMW announced the K1200S with a new front suspension that appears to be based on the design. As of 2006, Duolever is installed on the K1200S, K1200R and K1200GT.
Coaxial steering front suspension [edit]
Developed by MotoCzysz for their C1 and received US Patent 7111700 on September 26, 2006. Defined as the front part of a motorcycle or bicycle, having coaxial steering and suspension elements, as well as a telescopic fork. The weight of the steering fork is significantly reduced due to the fact that the suspension components are placed in a central position, coaxial with the steering column. The seat height can be adjusted without loosening the forks in the triple clamps.[7]
This particular fork, implemented on the MotoCzysz C1, also has adjustable travel from 89mm to 101mm. [8]
Non-forks [edit]
Main article: Hub-center steering
Yamaha GTS1000 suspension
There have been several attempts to implement front steering and suspension without using anything that could be called a "fork". Examples include hub-and-spoke steering used in the early 1920s on the Hep-A-Car,[9] and implemented in the 1990s on the Bimota TESI[10] and Yamaha GTS1000[11]
The single-sided beam "fork" was used by the German firm Imme[12][13] between 1949 and 1951[13].
Mead & Tomkinson Racing competed in endurance racing in the 1970s with the "Nessie", a Laverda-based center-steering race bike. [14]
This is a fork
An integral part of the designer's chopper is the front forks of insane length and design.
However, the telescopic fork guide tubes cannot be extended indefinitely. The huge span from the lower beam to the wheel axle will bend like a high jump pole. In this case, it is almost impossible to control the motorcycle. That’s why the DIYers remembered the good old design of the short-link front wheel suspension. Even Honda used such a suspension system on one of its new products last year (naturally, it was a chopper).
With all the apparent variety of designs of short-lever forks, they all come to a common denominator: these are two powerful support pipes, two levers swinging on them and a rod (rods) connecting the levers with a spring system and a shock absorber (usually hydraulic, usually located near the yoke).
Take serious care of the material - find reliable support pipes with a diameter of at least 38 mm. Make the traverses from D16T duralumin or any simple steel, because the chopper is not afraid of excess weight.
The remaining parts are not so large, and choosing pipes for the rod connecting the levers to the spring will not be difficult. Select steel plates for the levers themselves.
Begin construction by making traverses. The bottom one will be the most common (photo 1), and on the top one, provide attachment points for supporting the spring. This support must be able to rotate around its axis - when the suspension arms move, the rod will swing slightly relative to the support pipes.
Assemble the traverses on the steering column of the motorcycle frame and drag the support pipe blanks closer. Now is the time to determine how long to make them. Place the frame with the rear wheel on the blocks in the position it would be in if the motorcycle were standing on wheels. Insert the support pipes into the traverses, roll up the front wheel and figure out where the attachment points will be for the rotation of the suspension arms. Have you figured it out? Cut off the excess.
One of the difficult tasks when creating such a design is the manufacture of reliable hinged joints of the support pipes and suspension arms (photos 2, 3). We can offer options: bronze bushings (in the photo, by the way, equipped with grease fittings), ball bearings or needle bearings from the Volga front suspension pins. All options are good, it's a matter of your capabilities and taste. Use the same hinges to connect levers and rods. This will add torsional rigidity to the entire structure, which in turn will have a positive effect on the handling of your chopper.
Now proceed to creating the spring component of the front wheel suspension. The rod that transmits force from the levers to the spring can be whatever your imagination creates. We offer “practical industrial”: angry, reliable, iron-clad (photo 4). The rod rests on the spring, the spring rests on the yoke. In the photo, the spring from the Ural is reinforced with a thinner one installed inside the first one (photo 5, 6).
Reverse travel of the suspension must be limited. At a time when hydraulic shock absorbers had not yet appeared on motor vehicles (they, as a rule, also serve as a suspension travel limiter), a spring served as a limiter. In the photo it is located above the upper traverse. But this is a tribute to style. Those who drive a lot would rather prefer a conventional hydraulic shock absorber (for example, from the rear suspension of a Ural or Izha).
About little things. If you are not an orthodox follower of the chopper idea, then you can easily install a front wheel brake on your motorcycle. The simplest option: a standard wheel with a brake plate from Tourist, connected to a fork, with a rod on hinges. If you want a disk one, attach the bracket to one of the suspension arms.
And then, of course, there’s chrome—lots of chrome. Unimaginable steering columns and high-quality internal hexagon fasteners will decorate the device.
text: Roman Agishev, Igor Marchenko photo: Roman Agishev
Why is there a motorcycle in Last Day (the benefits of owning one)?
So let's summarize for clarity the advantages of the chopper in the game:
- the opportunity to visit a closed location (Halt on the side of the road)
- assistance in passing certain locations
- You can put your loot in the motorcycle (from 4 to 8 cells)
- if you run out of energy in the game, you can ride all over the map without restrictions, as long as you have gas
Of the minuses, I can only say one thing, this is the availability of gasoline, if it is not there, then it will take a very long time to collect it (but this all works out if you are doing a raid, there is a lot of fuel or coupons for the bunker)
Types of motorcycles and choppers in Last Day
Further in the game, a garage was introduced in 2022, which made it possible to create three additional types of motorcycles, each of which has its own features and characteristics.
Regular chopper
This is the very first motorcycle that you get after you assemble a tank, a fork and two wheels, it has 4 cells of capacity and average fuel consumption
Off road bike
This is one of the best motorcycles in the game, has moderate fuel consumption, maximum capacity of 8 cells (but for this you need to upgrade it to level 3, blueprints can be found at the gas station)
an off-road bike and its trunk with 8 cells - very convenient to go to locations with a lot of loot
Military motorcycle
I didn’t really understand its joke, but according to its characteristics, it simply does more damage if you want to crash into a crowd of zombies, it has four capacity cells
