Elja
The definition of efficiency, speed and capability. Through simplicity. At Lauf we don't cross rivers for water.
September 18th
LSP — Lauf Single Pivot
A true single pivot. Without any supplemental links & pivots driving the shock.
But not the “old fashioned” single pivot you might have seen before.
“LS” is not short for Leaf Spring
Lauf made a name for itself with its leaf spring suspension fork. Optimized for smaller hits and vibrations. We’re still as much in lauf with that concept as the day we came up with it. Its instant suspension reaction, zero-maintenance and ultra-low-weight set it in a class of its own for gravel bikes. However, MTB suspension and gravel bike suspension are very different engineering tasks.
Gravel bikes are mostly subject to vibration from rough surfaces. Gravel bikes benefit from a “low-pass filter”, that wipes out high-frequency “stuff” with minimal friction and energy loss. This is done efficiently by the undamped leaf-springs of Lauf gravel suspension forks.
MTB suspension should be good at dealing with larger impacts, eating up impact energy through damping. Hence, we needed a damper in our system. And, when we add a damper, we might as well add a spring at the same time. Modern bike rear-shocks conveniently combine both.
We did not set out to incorporate leaf springs into MTB rear suspension. As that would be approaching things from the wrong end. We set out to simplify MTB rear suspension where we could, while maintaining optimal suspension performance.
LSP has leaf springs
LSP ended up incorporating leaf springs! Just not in the way we (or you?) expected.
Don’t cross a river for water
Studying other suspension systems made us realize that if we chose a good pivot location for a single pivot suspension system, there really wouldn’t be gains from adding multiple pivots, links or sliders. In fact, we think a lot of placebo-medicine is being thrown around in the industry. Stay tuned, a detailed video-analysis of some key MTB suspension systems goes live October 31st.
Most MTB rear suspension designs locate their effective center of rotation in a similar area, for good reasons (reasons we’ll cover in our upcoming MTB suspension video-analysis). They however reach their targeted center of rotation through various methods, avenues and alleys.
At Lauf we don’t like crossing rivers for water. We simply placed our main pivot in the right spot. In a simple single-pivot manner. Not via needlessly complicated measures.
What does LSP do?
Why don’t all bikes use simple single pivot rear-suspension? And how does LSP improve upon older designs?
- Flat leverage ratio curve - Decades ago, multi-link suspension designs introduced the (awesome) possibility of ramping up their coil-spring suspension stiffness towards the end of suspension travel. Giving you responsive suspension that still didn’t bottom out all the time. However, it’s like nobody got the memo that modern air shocks have volume spacers to achieve exactly this. When studying leverage ratio curves of modern multi-link XC/Trail bikes, one finds that they are generally pretty flat, i.e. they are not utilizing their ability to provide a variable leverage ratio through their linkage system. Because, why would they? When the air-shock already does it.
- Lack of lateral stiffness - The way single pivot rear suspension designs are generally executed, there is a lot of lateral flex. This is where LSP comes in with its:
- Bracing-Box. Firmly bracing the left and right swingarms together (crucially) behind the seat tube. Resulting in an order-of-magnitude laterally stiffer structure than if one would go the traditional route of bracing the sides together in front of the seat tube.
- Oversized main-pivot bearing. BSA/DUB bottom bracket main pivot. For maximized anchoring strength and stiffness.
- Maximized main pivot spacing. For a maximized bracing angle.
- Oversized shapes. Where appropriate for stiffness.
3. Lateral loading of rear shocks - Some single-pivot designs expose the rear shock to undesirable lateral loads (in extreme riding scenarios). This is where LSP employs “leaf springs”, or as we call them, “flex-arms”. The flex-arm design doesn’t provide suspension, but it “greases up the system” and prevents it from damage. It takes advantage of the distance from rear shock to the Bracing-Box in the LSP design, to provide lateral compliance between rear wheel and rear shock when needed.
4. When bike brand X has 4-bar linkage rear suspension, this tends to make bike-brand Y want to come up with a 5-bar linkage system. More is more, right?
LSP is here to improve your Quality of Life Index and give you a fresh breath of simplicity and singletracks.
LSP is single pivot rear suspension, done the Lauf-way!