Parallelogram Suspension

Parallelogram Suspension was first introduced commercially in 1985 on the Magni "Le Mans". Magni called the system Parallelogrammo. This new suspension system eliminated the torque reactions normally associated with shaft drive motorcycles and enabled the bike to perform similarly to a chain-drive unit. Similar systems have been developed by other manufacturers.

BMW's Paralever rear suspension on an R1200RT

Paralever is BMW's version of the system. It allows the driveshaft to pivot along the same axis as the sprung rear frame due to the addition of second link between the rear drive and transmission. Paralever was originally introduced in 1988 R80GS and R100GS motorcycles and provides a reduction in the phenomenon known as "shaft jacking" where the rear of the motorcycle would lift skyward under certain riding conditions.

Moto Guzzi introduced a variant of the system it named the Compact Reactive Drive Shaft system (patented and named Ca.R.C.). The main difference is that the driveshaft is free to float into its structure providing much softer feedback from transmission. Additionally, the upper arm of the Ca.R.C. is not part of the structure but just a guide to close the geometry of the suspension (it means that, differently from BMW version, the suspension will work also with a broken upper arm).

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