Editing Swingarm (section)

==Squat and shaft-jacking==

"Squat" occurs because the top of the final drive chain run pulls the swingarm upwards; "shaft-jacking" occurs because the shaft drive bevel gear tries to "climb up" the large bevel gear in the wheel hub, thereby pushing the swingarm downwards and away from the frame.<ref>{{cite book |url=https://www.academia.edu/42812180/Motorcycle_Handling_and_Chassis_Design_the_art_and_science |author=Tony Foale |title=Motorcycle Handling and Chassis Design: The Art and Science |via=www.academia.edu |ISBN=9788493328634}}</ref>

Shaft-jacking can be minimised by devices such as parallelogram swingarms. A practical way to minimise squat on a chain-drive bike is to locate the final drive sprocket as close as possible to the axis of the swingarm pivot;  the ideal solution is to make the final drive sprocket and the swingarm pivot concentric, as was done on the [[Hesketh V1000#History & Development|Hesketh V1000]].