This Shock's Piston Disconnects at High-Frequencies - Taipei Cycle Show 2019
Motion Engineering says that their shock's main piston ''disconnects'' above a certain frequency.
Matthieu Alfano, the engineer behind Motion Engineering, doesn't do things like everyone else, with their 170mm-travel linkage fork employing a single carbon leaf spring, carbon legs, and a thru-shaft damper of their own design that doesn't need an IFP or bladder to do its job. The result is fork that might scare people off with its looks, but Alfano also claims that it's the only one on the market with true anti-dive abilities due to where he's placed the pivot points. Physics and stuff.
Motion has been working on something a bit more traditional looking, though, at least on the outside. The Flow EVO shock's internals are in the process of being patented and Alfano didn't want to go too deep with an explanation quite yet, and all they had in their booth was a rough-looking 3D-printed model, but it sounds like there are some neat things happening inside of it.
First, let's take a look at what we do know. Both bottom-out and top-out will be controlled hydraulically rather than by bumpers or springs, with position-sensitive valves at each end of the stroke that use oil displacement to slow down the action.
First, let's take a look at what we do know. Both bottom-out and top-out will be controlled hydraulically rather than by bumpers or springs, with position-sensitive valves at each end of the stroke that use oil displacement to slow down the action.
The 3D-printing is rough, but Motion do have functioning prototypes.
Alfano didn't have one apart to show, but it's something that's been put to use in the motorbike world and some mountain bike stuff as well (Manitou's HBO system, as well as Fox's older dampers), and it makes for bottom-out control that's independent of other settings.
Things get a little murkier when we get to something that Motion Engineering refers to as the High-Frequency Filtering piston. ''Oil has a mass and therefore opposes a resistance under motion,'' Alfano explains in their tech sheet, and the higher the shaft speeds, the more this can affect the suspension action. But get this: ''Above a certain frequency, the piston is disconnected and doesn't transmit any more oil movement,'' with Motion saying that this keeps high-frequencies from being transmitted to the bike and rider. Basically, the claim is that this allows them to separate impact forces that require damping from much smaller, high-frequency hits where you might want your suspension to be as open and free feeling as possible.
The advantage, I'm told, are considerable gains in comfort and traction.
This thru-shaft damper is used on Motion's 170mm-travel, anti-dive linkage fork.
What does it look like? No idea, but Alfano did let slip that there are no shims on the main piston like you'd usually see, with the damping circuits being located in the piggyback like a twin-tube system. And check how the piggyback is connected to the body in two places; oil flows through one passage during compression, and then out through the other during rebound.
Adjustments will include three-position compression and the usual low-speed rebound dial. The shock with be available by this coming summer and Motion will be offering it in all the usual sizes and trunnion mounting as well.
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I doubt its that simple
It looks more like a twin tube
singletrackworld.com/2019/03/singletrack-newsdesk-5-yt-decoy-rockshox-35-gee-atherton-sick-and-more