Sarrus mechanism for front suspension


New Member
Nov 19, 2018
As weird suspension designs have come to rise, I think that the main benefits would be less maintenance and brake dive mitigation.

The most common alt design I've seen is the use of four-bar linkages and I too think that it's a robust design to start with. (disregarding any weight junkies here) But even so, I think that what they struggle most is maintaining the motion of the fork as suspension compresses.

I primarily think that the main use of linkages is to avoid using hydraulic shafts as much as possible, but they still mainly use them as linear guides. Some linkage designs lately actually avoided using these at the expense of parallelogram linkages having circular or arc-like movement outputs.

This really puts off majority of the riders as we have a tendency to resist change, especially if it feels funny or weird and we'd have to adjust our riding styles to compensate.

So I looked into straight-line linkage mechanisms in the hopes of finding a suspension design that simulates or imitates the same linear movement as telescopic forks but instead with the use of linkages. I had a hard time looking for a practical one as, probably like most bike manufacturers, I naively looked at 2D or planar linkage mechanisms. I eventually found a 3D linkage system called a Sarrus linkage, where the linkages themselves maintain the trajectory to be linear (unlike parallelogram linkages) and in the same axis (like telescopic forks).

I think this could be a wondereful design, as you'd only need a compression spring to finish it off. The linkage is simple, robust, and could also be used as supplementary mechanism to provide rigidity in suspensions such as the inverted telescopic forks.

What are your thoughts on this one?

Similar threads

Cycling Equipment
Qui si parla Campagnolo