機器
activity
aluminum
background
bicycle
bike
brake
cable
cassette
chain
chrome
closeup
cogwheel
cycling
derailleur
dirty
drive
equipment
exercise
fitness
frame
freewheel
gear
gearwheel
industry
iron
isolated
machinery
macro
mechanism
metal
metallic
mountain
mtb
part
pedal
rear
shiny
speed
spoke
sport
sprocket
steel
technology
teeth
tire
transport
transportation
wheel