For this iteration of the gravity battery we obtained an almost complete, scrapped Yamaha trail bike.
The step-by-step build process was documented and detailed below. Although, this was the procedure used to build the gravity battery from this particular bike, it is also possible to use parts from the same bike to make a gravity battery in other ways.
Step 1. The key elements are tools, a workspace and bench and of course, the bike itself.
Step 2. Before dismantling, it's useful to make a note of the make and model of the bike as well as taking progress pictures. A time lapse video can also be useful in order to identify parts and processes at a later date. See our timelapse
videos for an example of how we did it.
Step 3. The engine and gearbox are among the most important elements required from the bike.
Step 4. The seat , fuel tank  and exhaust silencer  are removed followed by the front wheel and the steering mechanism .
Step 5. Removing some components like the radiator can be messy, requiring draining before removal.
Step 6. Remove the air intake, filter and shroud protecting the rear suspension elements.
Step 7. The majority of the easily accessible components have now been removed.
Step 8. The seat mounts and other unnecessary frame sections are cut away.
Step 9. Sharp burrs and other sharp edges are ground flat.
Step 10. The frame now has the minimum number of members to maintain structural integrity.
Step 11. The carburettor is removed.
Step 12. The cylinder head has been removed and the piston head is being detached from the connecting rod.
Step 13. The engine without the combustion chamber, fuel distribution and ignition components.
Step 14. The right side of the engine houses the clutch , the water pump  and the oil pump .
Step 15. Removing the left hand engine cover to access the generator and the final drive sprocket.
Step 16. Removing the cover reveals the generator  and final drive sprocket .
Step 17. The generator housing was cut to assist removal.
Step 18. The generator is pulled off its tapered shaft.
Step 19. The tapered mount is taken from the section cut from the generator body. This will become the interface point between the bikes mechanical and the electrical conversion systems.
Step 20. The rivets holding the remains of the generator housing and the tapered mount are drilled through.
Step 21. A larger bit is used to drill out the rivet heads.
Step 22. Any rivet heads that cannot be drilled out are ground away.
Step 23. The two elements, the tapered mount  and the generator housing  have now become separated.
Step 24. The tapered mount  needs to be attached to the gear  driving the final electrical generator.
Step 25. The tapered mount is secured in the lathe chuck  in preparation for removal of the locating stub .
Step 26. The tapered mount has been faced on one side, so it is flat and perpendicular to the axis in which the tapered shaft will fit.
Step 27. The hole positions on the tapered mount will be transferred onto the gear and drilled through to fasten the two elements together.
Step 28. The rear wheel is removed to allow the hub to be separated easily.
Step 29. The spokes are cut and removed from the hub.
Step 30. The stripped hub is remounted onto the rear forks and the chain tensioned by adjusting the hub position and locking it in place with the tensioning screw .
Step 31. The exposed engine is covered to prevent the introduction of debris which could hinder the smooth motion of the mechanism.
Step 32. The electricity generating motor  requires an interface plate for mounted onto a housing. This can be machined from a material with good mechanical stability like nylon 66 .
Step 33. A piece is accurately machined and parted off from the round bar of nylon.
Step 34. The pitch circle diameter (PCD) of the studs on the motor is measured with digital calipers.
Step 35. The PCD of the motor is transferred onto the machined nylon interface plate and drilled.
Step 36. The interface plate is bolted onto the motor.
Step 37. The nylon interface plate is trimmed.
Step 38. The sander is prepared by setting it to 90 degrees.
Step 39. The interface piece is sanded accurately.
Step 40. However, a more efficient motor has been acquired and a new mount is designed.
Step 41. Nylon spacers are machined to fit around the studs which formerly held down the cylinder head.
Step 42. The spacers allow the motor to be fitted at a suitable height.
Step 43. The motor housing is adjusted to enable the gears to mesh together.
Step 44. When the appropriate height has been established, the housing is bolted on with wing nuts.
Step 45. The stripped-down, re-purposed motorbike chassis, ready for testing. A descending weight will turn the engine, driving the gearbox from which an added gear will turn the motor which will generate electricity.