OK, so, technically this new Lauf Cycles rear hub design may have “hundreds” of factors of engagement per rotation, however that may as properly be infinite. Also referred to as instantaneous.
Both method, the impact is that the hub will interact so rapidly that it’ll really feel instant, and it does this with a really intelligent staggered, doubtlessly “elastic” pawl design that additionally softens engagement and could be positioned all through the hub’s complete shell.
Oh, and it does all of this with out magnets or springs.
How Lauf’s hub design works
The essential premise makes use of built-in pawls (701) made on an interior ring, every primarily it’s personal spring with a toothed hook on the finish to interact with the enamel (105) on the drive ring (102).
Nevertheless, it may additionally place the pawls on the outer ring and put the drive ring on the interior floor:
The pawls are staggered to interact at completely different factors within the hubs rotation, successfully creating extra factors of engagement with fewer-but-larger enamel. That is what number of present hubs work, normally having two or three pawls engaged at any time limit. For hubs that don’t want ultra-quick engagement, the pawls may very well be wider (Fig. 5b).
For faster engagement, a second set of pawls may very well be offset from the primary set (blue & orange picture on proper). Or…
…they might even use three units for even quicker engagement (Fig.12). Alternatively, they might use two or three rings in sync to extend power as a result of, admittedly, these pawls must be fairly skinny to suit into a standard hub design. Assuming that’s what Lauf has in thoughts, let’s keep on that monitor for a second.
Stretchy, Wavy Pawls
One other tactic for bettering complete engagement and power is to make use of a wavy form, permitting every pawl to “stretch” barely, simply sufficient such that one set engages first, then they stretch till the second set engages, then these stretch till a 3rd set engages.
The profit to that is that you’ve extra engagement all the way in which across the hub, decreasing lateral stresses between the cassette and freehub and hub shell.
And, assuming you apply an excessive amount of torque, that wavy design permits the pawl to breakaway earlier than it snaps. No, that might not be nice for you, however it could theoretically protect your hub. Nevertheless, check out Fig. 13 above for a second, after which scroll down…
1000’s of Pawls, Full-Width Freehub Our bodies
What in the event you stuffed your entire hub shell with rows of pawls, offering an enormous quantity of contact space, every barely staggered but in addition capable of stretch to permit different rows of pawls to additionally interact?
Not solely would this create insanely quick engagement, however it could present insanely stable engagement, too. Lauf says this additionally gives a a lot higher tolerance for pawls and ratchets being out of sync, which they are saying usually are as a result of real-world manufacturing limitations.
And, as a result of it permits for a full-width freehub physique that’s primarily a second axle, it could make your entire meeting much more sturdy, too. Figures 15-20 present a wide range of design choices the place a number of rows of pawls slot in varied locations and permit for a greater variety of freehub-to-hub shell interfaces.
Lauf additionally says the “stretch” of every pawl permits your energy to come back on progressively (nonetheless in a short time, thoughts you), which eliminates that loud KLUNK, notably on hubs with decrease engagement speeds. This will really cut back put on and tear in your drivetrain, too.
Whereas Lauf is thought for his or her bikes and forks, they’re at all times tinkering. Their doubtless aim is to license this design quite than turn into a hub model, too, however we’ve been stunned by them earlier than, so who is aware of?