Name: Learn the Intricate Crafting of Stationary Bikes | How It's Made | Science Channel
Uploaded: 2023-10-21T16:57:37.000Z
Duration: 9 min 15 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

The first stationary bike was developed by a London physician in the late 18th century to

exercise the joints of patients suffering from gout, rheumatic disorders or other

afflictions. The modern stationary bike is all about helping people stay fit to prevent

illnesses. On this stationary bike, magnets linked to the flywheel create tension that

causes the cyclist to push harder, making the workout truly an uphill battle.

Production starts with steel tubing for the base.

A probe locates the center of the tubing.

This reference point allows a computerized laser cutter to find the exact spots to cut

assembly holes with the assembly holes cut.

The laser slices the tubing to the correct length.

An automated system retrieves the part and transfers it to a holding area.

A worker inserts screws in the base part, which will attach it to the main frame.

Another worker now arranges the three tubular base parts in a welding fixture and

The fixture revolves and meets up with a robotic welder.

The robot welds the three parts together.

This completes the base of the stationary bike.

The bike's mainframe has been configured on the other side of the welding fixture.

The fixture rotates to serve up another base assembly to the robot, and the worker

collects the welded mainframe from the reverse side.

He grinds the welded seams smooth and gets rid of burrs on the steel.

Workers sandblast the metal, wash it, and apply primer.

After grounding the mainframe, another worker sprays electrostatically charged resin

Once it's baked on, this powder coat will provide a protective finish.

At another station, a 55 ton press punches holes into posts for the bike's handlebar and

seat. The holes are for adjusting the height of these parts.

Next up is the casting for mounting the handlebar to the post.

Using another press, the worker entrenches the top of the post in the casting.

He taps the casting with a rubber mallet to tweak the installation and sets the assembly

aside. At another station, a worker arranges numerous seat posts in tight alignment.

He drapes a stencil of sequential lettering on top of the posts.

He dips an etching wand in a chemical solution and then moves it over the letters

This burns the letters into the steel, providing markers for height adjustment.

An assembler drives a wedge into one of the bike's two crank arms to create a hole that

He checks the depth of the hole with a gauge.

He inserts the end of the axle in the hole and, using a press, pushes it into place.

He measures the hole from the other side of the crank arm, and confirms that the axle has

He then bolts the assembly to a precise torque.

He locks the crank arm assembly in a lathe.

He slips a foam sleeve over the axle to protect it from shards of flying metal.

As a tool machines the part of the crank arm that will ultimately hold the bike's pulley.

Another member of the team now assembles bearings to a wheel hub.

He slides two bearings with a spacer in a press.

He heats the hub in an oven, causing the metal to expand.

The machine presses the hub sandwich together.

As the hub cools, it shrinks for a tight fit to the bearings.

He installs a retaining clip in the hub to also keep it together.

Next up are the holders for the magnets that create resistance on the flywheel.

A worker places each one in a fixture to inspect the dimensions.

He then checks the strength of the magnets in a tester and satisfied.

This metal cage pulled into position by the magnets completes the magnetic field.

Stay tuned for more on the making of this stationary bike.

The assembler installs the magnetic resistance unit so that it swings from a

This bracket also holds the computer board.

He mounts the aluminum flywheel to the axle, sliding it between the magnets and the

He caps the flywheel hub and secures the cap with screws.

The torsion spring equipped cover completes the stationary bikes tension system.

He assembles the crank, arm and axle to the bike and installs a bearing.

Then the bike moves on to the next station.

Another worker places an alignment tool on the back axle.

He loops an elastic belt with grooves around the small pulley on the flywheel, and around

the larger crank arm pulley linking the two.

He inserts another tool into the crank arm and turns it to better wrap the belt around

He installs four flat bushings in the handlebar post.

These bushings make it possible for the handlebar to be raised and lowered.

He applies a decal with the height indicators made of a rugged synthetic

material. The decal encases three sides of the metal post and this protects it from

abrasion. He bolts the second crank arm to the axle and torques it to the

He slides the seat stem into the post and tightens the adjustment knob to lock it in

place. He inserts the handlebar post into the bike frame and fishes the gear, cable and

He secures the handlebar post with the adjustment knob.

He connects the communication line to the resistance system's computer board.

He links the gear cable to the resistance system and tests its functionality.

Satisfied, he tightens a nut at the side to secure the cable.

Another worker installs a plastic cover on the drive train.

This will protect the cyclist's legs from the pulley system and shield the metal

For added moisture protection, she applies sealer around a welded reinforcement on the

bike frame. She then encases the fork of the bike with more molded plastic.

She now places a magnetized microphone on the axle and spins the flywheel at a high

The bike must operate noiselessly and the decibel meter confirms the noise level is

negligible. She also feels the frame for unwanted vibrations.

She now sets the location of the magnetic resistance mechanism using a special tool.

This calibrates the resistance so that the handlebar computer can find it and display