Broken Motorcycle: can be obtained by looting the car workshop, garages, from roads and gas stations.

Motorcycle Spare Parts: can be obtained from looting the broken motorcycles, car workshops and garages, or from disassembling broken motorcycles. Another way is by trading 10 Steel for 1 Motorcycle Spare Part in the Chelyabinsk Survivor Camp.

Spark Plug: can be obtained by looting car workshops.

Machine Oil: can be obtained by looting garages or car workshops, but also by disassembling other vehicles (not the Bicycle)

Insulating Tape: can be obtained by looting several places, from ruins to garages, stores, houses and many more. Very easy to find. (and you probably have some by now)

Rubber Parts: can be obtained from several places, mainly garages and workshops. Easy lootable material.