If you’ve had a look for a new set of wheels in recent years, you might have been left with a sore head while trying to decide between hooked and hookless rims. We speak to some of the key brands in the world of wheels to find out their take on the benefits of each system.
First off, you might only just have decided that you’d like to try tubeless and now we go and tell you that there are some minutiae of rim tech that we’re telling you to choose between. With that in mind, here is the difference between hooked and hookless tubeless rims.
They look just like your regular clincher rims and, to an extent, they are. Hooked rims support tubeless-ready and standard tube-type clincher tyres. Hooked rims, as the name might suggest, feature hooks at the top of the rim wall.
As the name also suggests, hookless rims do not feature those hooks to hold the tyre onto the rim. The system relies on tyre pressure, specially designed tyre beads and tight tolerances to hold the tyre onto the rim.
The cycling market is rather late to the hookless party. Watch a Moto GP race and the riders are getting their knee down while riding hookless wheels. If you’ve got a relatively modern car, you’ve most likely got hookless rims on the wheels too. So why doesn't your bicycle?
We wanted to clear up some of the confusion surrounding the hooked vs hookless debate so we asked Pacenti, Campagnolo and Zipp for their take on topics such as rim construction, performance and why each brand chose the system that they did.
Does hookless or hooked offer advantages for rim construction?
When it comes to rim construction, all three of the wheel brands that we asked are pretty clear about where they stand. Hookless rims are both easier in terms of manufacturing the rim and are stronger when in use.
Zipp says that thanks to the straight sidewalls, “we can use hard tools (ie. steel) to mould the tyre cavity of the rim, as opposed to the silicon mandrels that are generally required on rims with hooks. Steel moulds give us much greater control over the manufacturing process.”
This, Zipp claims, “ensures better compaction of the carbon fibre through the rims which make for a stronger rim with higher impact resistance. It also allows for better resin distribution, which means the rim can be moulded with less resin so the rim is lighter.”
That, for Zipp, makes for an easier time when manufacturing the wheels. But for the end-user, there is another benefit to this with Bastien explaining that they are able to “hold tighter tolerances in the tyre bed cavity, which results in a more precise tyre interface which is, therefore, safer to ride.”
Campagnolo suggests that the benefits of hookless can be achieved on a hooked rim, with some additional engineering effort that the Italian brand says can be found on the recently released Bora Ultra WTO wheels. Campagnolo claims that this is achievable because it owns its full manufacturing process and so can control all aspects of production.
Luke from Pacenti pointed to the benefits when running lower pressures on a gravel, cyclocross, or mountain bike setup. When the straight sidewall contacts the ground due to an object such as a tree root or rock compressing the tyre, the stronger hookless rim stands a much better chance of surviving intact versus a hooked rim.
Of the manufacturers that we spoke to, Zipp was the clearest cut on which system offered a performance advantage. Alongside the improvements to the construction process, they suggest that the lack of hooks “means a cleaner transition between the rim and the tyre which results in a more aero setup.
There is also the question of total system efficiency, something that Zipp began talking about with the launch of its latest 454 NSW, 404 Firecrest, and 858 NSW wheels.
“Hookless also allows for a larger internal width, without affecting the outside width of the rim. This creates more volume and more support for the tyre, which enables lower tyre pressure and better vibration damping; without affecting the aero profile of the rim. As a result, the rim is plain faster in the real world: according to an independent test made by Aerolab, our new 454 NSW with hookless rims is 10 watts faster than the previous generation.”
If that wasn’t enough, Zipp also points to an environmental marginal gain which also has a positive impact on pricing for customers.
“Overall, better control of the manufacturing means less scrap, and reduction of the costs means a lower price. This allowed new price points for us, such as 303 S at under £1,000 and gave us the chance to reduce the retail price of our Firecrest wheels by $600.
"Being easier to manufacture, hookless rims create less waste so they’re a little better for the environment.”
Zipp is one brand that has passed on some of their cost savings to the customer, but not all brands will do the same. A set of hookless carbon road wheels still represents a significant investment for many normal cyclists so lower costs isn't something that can be applied across the board.
And while there are certainly performance benefits associated with hookless rims, Campagnolo suggests their hooked wheels "get the same easiness of installation and aerodynamic match with the tires thanks to the evolved 2 way-fit profile" as well as the new manufacturing process.
Campagnolo continued to explain that “our 3D scan also showed that, when it comes specifically to aerodynamics, the majority of tyre manufactures have not developed hookless specific models yet so the tyre beads/side junction is designed to match actually better with a hooked than with a linear rim flange,” so if you’re not running tubeless-specific tyres, you might be better off with hooked rims.
Luke from Pacenti also told us that he finds hookless rims are more prone to spoke tension drop after the tyre is mounted and inflated. This tension drop is common to tubeless wheels and is caused by more air pressing onto the rim compared to a standard tube-type clincher. The simple solution to this, Luke says, is that, where possible, Pacenti installs tyres for the customer so that they can re-tension, re-dish and re-true the wheel before it goes out.
Zipp’s Bastien Donzé summarises it succinctly, saying that “hookless offers so many benefits to the end-user while being easier and cheaper to make; it’s clearly the future.”
It’s a feeling that Pacenti echoed with Luke Humphreys also stating that he feels that hookless is the way that the market is heading, though his reasoning was that the tighter manufacturing tolerances are the key to the better experience for the end-user.
Campagnolo suggested that consumer awareness around the environmental impact of the products that they buy is also influencing manufacturing decisions.
“If we, as manufacturers, will be all able to reduce the related production waste it could really have a huge impact on a global scale. Of course, the challenge is still to keep, and possibly improve, the riding performance and the hookless seems a good direction to this respect.”
But while there are clear advantages, Campagnolo also says that a key factor that hookless isn't yet able to match hooked rims on is tyre choice. Riders that opt for hooked rims still have a much broader choice of which tyres they use on their wheels and if you're a fan of a lovely set of cotton clinchers with their high thread counts and supple casings, hooked is still the way to go.
While all of the brands that we spoke with are in no two minds about where the market is heading, there is one rather vital bicycle component that is holding the hookless standard back and it is that smaller choice of compatible tyres.
Brands such as Zipp, ENVE and Giant list a range of tyres that are compatible with their respective hookless rims, but the issue still remains that the end-user is limited when buying new tyres.
The revised ETRTO standard introduced back in 2019 and supported by brands such as Mavic, has attempted to improve things for consumers, but there is still no requirement for tyre companies to make their tyres compatible. This leaves customers needing to check their wheel manufacturer’s list of approved tyres or risk a setup headache.
There is also the not so small matter of tyre pressure. Campagnolo points out that “hookless rims forcedly express a maximum tyre pressure (below 5BAR/72psi) in use which is not only different to the maximum one expressed by the majority of tyre brands” which he says can cause confusion for end-users but “also far from what a huge percentage of consumers are still riding.”
What this means for the average cyclist is dependent on their riding preferences. While road riders that are looking for pure speed will likely be sticking to their 25mm tyres inflated to well over that 72psi figure, many recreational road riders are favouring the floatier, more comfortable ride quality of wider tyres which are run at lower pressures.
Zipp pointed us back to the fact that “hookless is a fully standardised interface: hookless rim dimensions have been normalised in ETRTO back in 2019, and have now been included in ISO as well.”
This, Zipp says, gives them confidence in their hookless wheels and the tyres that they recommend, a point that Pacenti also highlights as one of the key factors in converting general riders to tubeless.
Campagnolo, on the other hand, recently released its top of the line Bora Ultra WTO wheels which we have reviewed. These use a hooked rim design which is tubeless-ready and for Campagnolo, it is the lack of maturity in the tubeless tyre market which is the reason for sticking with hooked rims for the time being.
Campagnolo says that they “are not neglecting its [hookless] potential in the future but, for today’s average consumer, hooked systems (that we have in use) are simply still safer and more versatile.”
While Pacenti and Zipp are both fans of hookless rims from a construction and performance point of view, it is telling that Campagnolo has stuck with a hooked design for its latest top-end road wheelsets.
Currently, the limiting factor for hookless is tyre compatibility and the limit on tyre pressure which, for many performance-minded road riders, means that hookless rims just won't cut it. If you're sticking with 25mm tyres and looking to run over 72psi, you'll want to stay with hooked wheels for a while yet, and even if you don't want to you'll probably have to.
But for riders that have moved over to using larger volume tyres and run the lower pressures that they allow, hookless rims can provide easier setup, more safety, better impact protection at lower pressures and a lighter, slightly more affordable rim.