Just lately in Girona for Sea Otter Europe, wheelmaker Lavelle confirmed us the insides of how their practically immediate engagement clutch hub works. It’s a reasonably uncommon resolution to see on premium light-weight wheels, and was surprising inside these 5-spoke gravel race wheels.
However that is solely a quick glimpse of the precision tech on provide from Lavelle. They construct monocoque 5-spoke wheels for gravel and mountain bikes, but additionally historically laced carbon wheels from street to BMX. And apart from the 0° clutch engagement, in addition they have a 7.5° choice with uniquely machined 48T ratchet engagement inside. Plus, there’s much more attention-grabbing tech that I’ll need to dive into later – like hub cooling fins, ti axles, and wavy carbon rims.
However now we’re simply getting began with Lavelle…
Lavelle 1440 POE sprag clutch hub provides 0.25° engagement
The moment engagement sprag clutch idea isn’t new – in biking or elsewhere.
It really works with numerous little ‘sprags’ contained in the hub that act like one-way pawls with rounded cams on the ends. They let the axle rotate freely in a single course with virtually no drag (freewheeling). However then, when it spins in the wrong way, they rapidly rotate into place, wedging themselves between the axle & hubshell for constructive engagement.
To work effectively, you want extremely exact and robust inside and outer metal rings for plenty of tightly-spaced metal sprags to press in opposition to. There can’t be any imperfections or deformation of any a part of the system, so it tends to be tough to fabricate and heavier than extra standard freehub options. We’ve been masking double-row Onyx clutch hubs because the early days of our platform. However apart from their barely lighter 1.5-row Vesper hubs proven to us as a 2017 prototype, Onyx hubs have remained comparatively heavy. However the immediate engagement is tough to argue with. And as soon as a rider adapts to it, they seldom need to return to slower engagement.
Lavelle’s resolution has been to extend the diameter of a single-row sprag clutch straight over a big bearing to deal with the excessive engagement forces wanted. That additionally helped maintain weight down, and minimized the surfaces that needed to be ultra-precise.
Chatting with the precise angle of engagement, Lavelle (and Onyx) discuss in regards to the sprag clutch idea as being 0°. However in actuality, the 46 sprags inside this specific hub do have to really rotate, camming into place to have interaction. Lavelle calculates that rotation into place to be successfully 1440 factors of engagement, for an imperceptibly small 0.25° engagement angle.
…or a 48 POE ratchet hub with 7.5° engagement
Now, perhaps you don’t need or want immediate engagement. Lavelle additionally builds a street hub with 48-tooth ratchets as effectively for nonetheless fast 7.5° engagement. There are a couple of tips right here.
First, 3-dimensionally conical tapered tooth on the ratchets guarantee such excellent engagement that Lavelle can machine the ratchet straight into the alloy freehub physique to avoid wasting weight. In addition they prolong the toothed interface of the ratchets out to absolutely the edges of the freehub physique and hubshell, maximizing floor contact space. And eventually, the floating ratchet ring contained in the hub is completely pressed in opposition to the freehub ratchet with an ultra-precise multi-turn wave spring to make sure uniform engagement all the way in which round.
Extra good hub tech
Past two types of engagement, Lavelle machines their hubs with patented exterior cooling fins to extend hub shell floor space considerably (~17% relying on the hub) with out including a lot weight for a giant increase in disc brake warmth administration, necessary for prolonged descending.
In addition they all function stiff titanium axles, mentioned to be 10x stronger than aluminum axles, and a 65% improve in axle stiffness. That works along with 4 units of outsized “completely aligned bearings” per hub to make sure easy working and lengthy lifespans.
The Spanish-made hubs had been initially developed to kind the core of their Fireroad monocoque carbon wheels, however now Lavelle has additional refined them to be constructed into extra standard street, gravel & mountain bike wheels. They usually additionally provide the hubs individually as an 830€ hubset to lace into your individual {custom} wheel builds.
hub weights (claimed):
- centerlock straightpull street/gravel: entrance 110g, gravel clutch rear 330g, street ratchet rear 222g
- 6-bolt J-bend mountain/enduro/DH: entrance 149g, MTB clutch rear 420g
Lavelle Fireroad monocoque 5-spoke carbon gravel wheels
The 5-spoke carbon gravel wheels appear to be have been Lavelle’s origins, and it’s the place they’re refining innovation. These wheels function a 25mm hookless inside width, measure 32mm extensive exterior and are 40mm deep between the spokes. Lavelle builds them with a {custom} carbon layup tailor-made to every rider’s weight and using fashion in Galicia, Spain. They usually usually function Lavelle’s ultra-fast-engaging clutch hubs. However you too can get a set now prepared for a Categorised Powershift 2-speed internally geared rear hub, too.
The usual wheelset sells for 2989€ with the moment clutch hub. Weight is mostly round 1600g for the set (Lavelle claims 1060g for the carbon rim & spoke components), together with the marginally heavier 0.25° engagement clutch hub internals and non-round hub shells bonded into the carbon physique. That’s quite a bit in comparison with standard light-weight gravel wheels.
However Lavelle claims their stiffness, aerodynamics, instant-engagement, and the impression sturdiness of the three.5mm extensive beads greater than makes up for it.
Lavelle’s engineer let me take a spin on his personal gravel bike kitted out with these made-in-Spain 5-spoke carbon Fireroad wheels and weight wasn’t in any respect what I seen. It was the successfully immediate 0° hub engagement that instantly grabbed my consideration.
It’s virtually an unreal sensation for there to be an immediate response out of your pedals to the tires on the bottom after coasting silently. However I can definitely see how you might come to like the direct really feel whereas using, particularly over irregular terrain.
Many extra Lavelle wheel builds choices, too
Past the 5-spoke gravel & all-mountain wheels and people distinctive hubs, Lavelle additionally builds loads of virtually standard wheels. These vary from 2400€ to 3100€ relying on which hubs and rims you select. However, there are standard 23.5mm inside aero street shapes in 50 or 60mm depths, as mild as 1200g. Extra curiously wavy all-road wheels in 50 or 65mm depths with ratchet hubs and 25mm inside width, from 1330g. 32mm inside gravel wheels from 1370g. And even enduro and World Cup-proven DH wheels with variable rim widths and immediate clutch hubs.
The one unifying precept is that the carbon is all laid up in Spain, the hubs are all machined in Spain, and wheels are all laced in Spain. All the pieces is custom-built-to-order, so lead occasions are round 5 weeks from settling your order.