WILD RIDE
GET A GRIP!
staz
staz
marco
marco
noriko
noriko
zak
zak
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BikeSim
Zak
brakeset
ANASTASIA IS COOL!
Tyre Catalog
Slick Treads
Spring collectio
Spring collectio
Brakes
closeRim brakes
Rim brakes press two rubber pads against the side of the wheel rim. Friction between the rim and the rubber slows the bike down.
Rim brakes are not as good in wet weather when the rims get wet and friction is reduced.
Rim brakes are not as good in wet weather when the rims get wet and friction is reduced.
Disk brakes
Disk brakes are mainly found on mountain bikes for off-road riding. They are similar to those used in cars and motorbikes. To slow the bike down, a brake pad is pressed against a metal disk attached to the wheel axle.
Disk brakes are more powerful and reliable than rim brakes, but are heavier and more expensive.
Disk brakes are more powerful and reliable than rim brakes, but are heavier and more expensive.
Hub brakes
Hub brakes are enclosed in the hub of the back wheel and are similar to the drum brakes used in some cars. Some are operated by cables and levers, and others by the rider turning the pedals backwards.
Being completely enclosed, they are unaffected by weather and need little maintenance. However, they are heavier than rim brakes and more complicated to repair.
Being completely enclosed, they are unaffected by weather and need little maintenance. However, they are heavier than rim brakes and more complicated to repair.
Tyre catalogue
closeSlick Treads
Spring Catalogue
Clinchers, tubular and tubular clinchers
General purpose
Racing slicks
Training
Track
Cyclo-cross
Mountain bike
Mixed terrain
Extreme sports
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H2O(rain)
Sand
Move this spare wheel to the bike to change tyres.
Move this spare wheel to the
bike to change tyres.
bike to change tyres.
Select the scraper to remove
water or sand.
Select the water tap to wet the track.
water or sand.
Select the water tap to wet the
track.
Select the sand tap to make the track soft.
track.
Select the sand tap to make
the track soft.
the track soft.
FRICTION
ACTION
Forcemeter
About grip
Measuring force
| Tyre | No tread |
Force in bodyweights | max |
| Track | Soft & wet |
Pull down Marco's foot so that he pushes against the pedal.
Pull down Marco's foot so that
he pushes against the pedal.
he pushes against the pedal.
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About grip
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Marco needs tyres that grip the track well, especially when he pushes hard on the pedals or goes around corners.
We've fixed his bike to the ground so we can measure the grip between the rear tyre and the track.
Professor Bruce Elliott, Sports Scientist
Marco pushes down on the pedal to turn the chainwheel. The chainwheel pulls on the bike chain, which pulls on the rear cog and turns the wheel.
Professor Bruce Elliott, Sports Scientist
As Marco presses on the pedal, he creates an action force (the green arrow) that tries to turn the wheel. At first, the wheel doesn't turn. Another force must be resisting the action force.
Professor Bruce Elliott, Sports Scientist
Friction from the track, or friction force (the red arrow), is preventing the wheel from turning.
Friction prevents things sliding against each other. Tiny bumps on the road surface dig into the tyre rubber, causing friction and providing grip.
Friction prevents things sliding against each other. Tiny bumps on the road surface dig into the tyre rubber, causing friction and providing grip.
Professor Bruce Elliott, Sports Scientist
Force in bodyweights
FRICTION
ACTION
If Marco's action force becomes larger than the friction force, then the grip fails and the wheel turns. The meter shows how hard Marco pushes on the pedal. The reading is in fractions of a bodyweight. Watch what happens to the forces at normal speed and in slow motion.
Professor Bruce Elliott, Sports Scientist
Measuring force
close
To measure how hard Marco is pressing on the pedal, a sports scientist uses a force transducer under Marco's shoe. The result is recorded by the computer. Select the items in this diagram to see how they work together.
As Marco pushes down on the pedal, a force transducer measures how hard he pushes.
This force transducer is built into the pedal to measure how hard Marco pushes.
The electrical signal from the force transducer is boosted by this amplifier.
The signals from the amplifier are gathered and stored on the computer.
The computer graph shows how Marco's force on the pedal changes during one complete turn of the chainwheel.
Brakes
closeRim brakes
Rim brakes press two rubber pads against the side of the wheel rim. Friction between the rim and the rubber slows the bike down.
Rim brakes are not as good in wet weather when the rims get wet and friction is reduced.
Rim brakes are not as good in wet weather when the rims get wet and friction is reduced.
Disk brakes
Disk brakes are mainly found on mountain bikes for off-road riding. They are similar to those used in cars and motorbikes. To slow the bike down, a brake pad is pressed against a metal disk attached to the wheel axle.
Disk brakes are more powerful and reliable than rim brakes, but are heavier and more expensive.
Disk brakes are more powerful and reliable than rim brakes, but are heavier and more expensive.
Hub brakes
Hub brakes are enclosed in the hub of the back wheel and are similar to the drum brakes used in some cars. Some are operated by cables and levers, and others by the rider turning the pedals backwards.
Being completely enclosed, they are unaffected by weather and need little maintenance. However, they are heavier than rim brakes and more complicated to repair.
Being completely enclosed, they are unaffected by weather and need little maintenance. However, they are heavier than rim brakes and more complicated to repair.
Questions on grip
closeWhich tread will provide the most grip on a wet, soft track? (You may need to check the test results in your notebook.)
Grip depends on the amount of tyre rubber that is pressed against the track because this increases friction.
On a soft track, a smooth tyre 'floats' on the loose surface and skids easily. However, the knobs on a rough-tread tyre cut through loose material to the firm track below.
On a soft track, a smooth tyre 'floats' on the loose surface and skids easily. However, the knobs on a rough-tread tyre cut through loose material to the firm track below.
Correct
Which tread will provide the most grip on a wet, firm track with many hills?
The bigger the contact area between your tyre and the track, the better the grip will be. Which of these different tread types has the greater contact area?
Water on the track makes no difference: bicycle tyres push it aside and make contact with the track surface.
Water on the track makes no difference: bicycle tyres push it aside and make contact with the track surface.
Correct
Which tread will provide the most grip on a dry, firm, bush track with many corners?
On most firm surfaces, the best tyre is perfectly smooth because this gives the largest contact area and best grip. But on hard, rough, bush tracks where you have to turn a lot, the knobs on an off-road tyre press against bumps on the track surface and reduce the chances of slipping.
Correct
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zac
brake set
Rim brakes
Disk brakes
Hub brakes
Brakes
closeRim brakes
Rim brakes press two rubber pads against the side of the wheel rim. Friction between the rim and the rubber slows the bike down.
Rim brakes are not as good in wet weather when the rims get wet and friction is reduced.
Rim brakes are not as good in wet weather when the rims get wet and friction is reduced.
Disk brakes
Disk brakes are mainly found on mountain bikes for off-road riding. They are similar to those used in cars and motorbikes. To slow the bike down, a brake pad is pressed against a metal disk attached to the wheel axle.
Disk brakes are more powerful and reliable than rim brakes, but are heavier and more expensive.
Disk brakes are more powerful and reliable than rim brakes, but are heavier and more expensive.
Hub brakes
Hub brakes are enclosed in the hub of the back wheel and are similar to the drum brakes used in some cars. Some are operated by cables and levers, and others by the rider turning the pedals backwards.
Being completely enclosed, they are unaffected by weather and need little maintenance. However, they are heavier than rim brakes and more complicated to repair.
Being completely enclosed, they are unaffected by weather and need little maintenance. However, they are heavier than rim brakes and more complicated to repair.
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select Help.
Select Start to begin your investingation.