Explanation:

Bicycle and Bicycle Parts Industry :The state is the second largest manufacturer of bicycles and bicycle parts in the world. The Ludhiana cluster produces about 60% of the total bicycles manufactured in the country in the large and small-scale sector and more than 80% of the parts and components in the small and tiny sector.
The first indigenously owned bicycle-manufacturing unit, Atlas Cycles, was established at Sonepat in 1951 in the SSI sector in undivided Punjab. Hero Cycle Limited commenced production of complete bicycles in 1956 as an SSI unit in Ludhiana and became the world's largest producer of bicycles in 1989, with a record production of 2936076 units and entered the Guinness Book of World Records.
The machinery making industry of Punjab has played a very significant role in the industrial development of the country. This Is particularly true of the small-scale sector of the state engaged in the production of machines for the manufacture of a variety of industrial products. This industry includes diesel engines, tractors, oil expellers, textile machinery, etc. The industry is mainly concentrated in Batala and Ludhiana and produces a variety of machine tools of different sizes and types. Machine tools worth 80 crore and above are being exported annually from Punjab.