Essay:

Essay details:

  • Subject area(s): Engineering
  • Price: Free download
  • Published on: 7th September 2019
  • File format: Text
  • Number of pages: 2

Text preview of this essay:

This page is a preview - download the full version of this essay above.

Recumbent bicycle

A recumbent bike also called prostrate bike is a bike that places the rider in a laid-back leaning back position. The majority of recumbent riders pick this kind of configuration for comfort reasons; the weight of the rider is distributed serenely over a bigger range, upheld by back and rear end. On a customary upright bicycle, the weight of the body lays totally on a little portion of the sitting bones, the feet, and the hands.

A huge amount of recumbent models likewise has an aerodynamic pro; the leaned back, legs-forward position of the body of the rider displays a littler frontal profile. A recumbent bike holds the world record in speed for a bike, and they were banned from hustling under the UCI in 1934, and now race under the pennant of the Human Powered Vehicle Association (HPVA).

Recumbents are accessible in an extensive variety of arrangements, including: long to short wheelbase; large, little, or a blend of wheel sizes; overseat, underseat, or no-hands steering; and back wheel or front wheel drive. A variation with three wheels is a prostrate(recumbent) tricycle.

Recumbents bikes can be classified by their wheelbase, wheel sizes, steering system, faired or unfaired, and front-wheel or back wheel drive.

1. Wheelbase

Long-wheelbase (LWB) models have the pedals situated between the front and back wheels; short-wheelbase (SWB) models have the pedals before the front wheel; compact long-wheelbase (CLWB) models have the pedals either near the front wheel or above it. Inside of these classes are varieties, some types, and even convertible outlines (LWB to CLWB) - there is no "standard" prostrate (recumbent).

Long-wheel-base low-rider recumbent with steering u-joint (UA)

2. Wheel sizes

The recumbent bike has a back wheel is most of the time behind the rider and might be any size, from around 16 inches (410 mm) to the 700c (or 27" on some models that are already old, as on upright road bicycles of that time) of an upright hustling cycle. The front wheel is ordinarily littler than the back, despite the fact that various recumbents highlight double 26-inch (ISO 559), ISO 571 (650c), ISO 622 (700c), or even 29 x 4" oversize off-road tires. Bigger breadth wheels for the most part have lower rolling resistance however a higher profile prompting higher air resistance. Highracer devotees additionally claim that they are more steady, and despite the fact that it is less demanding to adjust a bike with a higher focus of mass, the wide assortment of prostrate (recumbent) outlines makes such speculations problematic. Another point of interest of both wheels being the same size is that the bicycle requires one and only size of inward tube.

One regular course of action is an ISO 559 (26-inch) back wheel ISO 406 or ISO 451 (20-inch) front wheel. The combination of the front wheel (small) and back wheel (big) has an important utility so that the pedals and front wheel are kept clear to each other, evading the issue on a short wheelbase prostrate called "heel strike" (where the rider's heels get the wheel in tight turns). A rotating blast front-wheel drive (PBFWD otherwise known as Moving Bottom Bracket prostrate) setup additionally overcomes heel strike subsequent to the pedals and front wheel turn together. PBFWD bicycles might have double 26-inch (660 mm) wheels or bigger.

3. Steering

On recumbent bicycles the steering can be generally categorized as

1. Over-seat (OSS) or above seat steering (ASS);

2. Under-seat (USS); or

3. Centre steering or pivot steering.

The OSS or ASS is generally immediate, the steerer follows up on the front fork like a handlebar of a standard bike yet the bars alone might extend well behind the front wheel (more like a tiller); on the other hand, the bars may have long rearward augmentations (at times known as King cycle bars). Another type of bar is the chopper-style bars that can be seen on LWB bicycles. Different from ASS, the USS is typically non immediate or on the other words is indirect, the bars connection to the headset through an arrangement of rods or links (cables) and probably a bell crank. The majority of tadpole trikes are USS. The recumbents with centre steered or pivot steered, for example, Flevo bikes and Pythons, might have no handlebars by any means.

Moreover, a few trikes, for example, the Sidewinder have utilized back wheel steer, rather than the more basic front-wheel steer. They can give great mobility at low speeds, however have been accounted for to be conceivably unsteady at rates above 25 mph (40kph).

A Flevo bike showing pivot steering (and FWD)

Types of recumbent bicycle

1. Mountain bike recumbents

Recumbent bicycles as many other bicycles when it has the right equipment and design, can be used for riding unpaved roads and off-road, in the same way that for conventional mountain bicycles. Due to their longer wheelbase and the way to which those rider is limited of the seat, recumbents are not as simple to use around tight, mainly curving unpaved single-track. Since 1999 it has been used wheels with large diameter, gearing of mountain and off-road (more rough terrain) specific design. Crank-forward outlines that makes climbing out of the saddle easier, for example, those RANS Dynamik, likewise could be utilized rough terrain.

2. Lowracers

One of the most common types of recumbent among the enthusiasts in Europe are lowracers.  These type of bike typically have two 20" wheels or a 26" wheel at the rear and 20" wheel at the front. The seat is situated between the wheels instead of above them. The extreme back position and knowing that the rider is sitting in accordance with the wheels instead of being on the top of them, makes this kind of bike the bicycle the most aerodynamic among recumbent.

Generally, as with upright bikes, recumbents are built and promoted with more than one seat, in this way joining the pros of recumbents with those of tandem bikes. With a specific end goal to keep the wheelbase from being any more than totally vital, tandem recumbents frequently place the stoker's crankset under the chief's seat. A typical design for two riders in the position of recumbent is the "sociable tandem", wherein the two riders ride one next to the other. There are likewise designs of hybrid recumbent, for example, the Hase Pino Allround that use a recumbent stoker in the front, and an upright pilot in the back.

6. Recumbent tricycles

Recumbent tricycles (trikes) are closely related to recumbent bicycles, but have three wheels instead of two. Trikes come in two varieties, the delta, with two rear wheels, and the tadpole, with two front wheels.

A tadpole recumbent tricycle is a recumbent made by Inspired Cycle Engineering with a transparent front fairing

There are some advantages of recumbent trikes that include:

•The rider does not have to separate from the pedals when stopped.

•The trike can be adapted low to empower mountain climbing while it has heavy load and at a moderate velocity, without losing stability.

•Recumbent trikes are extremely appropriate for touring of long distance since the agreeable rider position diminishes strain to the body of the rider.

•Recumbent trikes might likewise be more suitable for individuals with balance or appendage handicaps.

•As the trike stable, it makes them a decent beginning stage for adjusting into a velomobile.

In recumbent trikes there are some disadvantages that include:

•Many trikes are lower to the ground, so the rider is less noticeable to activity and less ready to see above autos. Banners can help, and trikes arrive in an assortment of styles, as do supine bicycles, so this simplification doesn't have any significant bearing to all circumstances.

•Three wheels mean half more grating with the ground, which can be discernible on unpaved ways.

•The more extensive position makes it harder to accomplish the same optimal design as a two-wheeled bike.

•The more extensive position can consume more space on trails and can make it troublesome traveling through entryways.

The notoriety of trikes has become altogether throughout the years as maturing children of post war America find the advantage of kept riding without the issues of parity and agony generally connected with customary upright bicycles.

...(download the rest of the essay above)

About this essay:

This essay was submitted to us by a student in order to help you with your studies.

If you use part of this page in your own work, you need to provide a citation, as follows:

Essay Sauce, . Available from:< https://www.essaysauce.com/essays/engineering/2016-4-3-1459713063.php > [Accessed 18.10.19].