Sapim spoke range explained
If you would like to purchase any spokes through us or would like any help in choosing the correct spoke for a wheel you would like us to build for you, please get in touch. Below is an overview of the spokes we offer and what applications they are best suited to.
The significance of spokes
A bicycle wheel can only be as good as its parts. A wheel is made of three main parts; hubs, rims and spokes. If any of these is poor then it will lead to a poor wheel. Even a stout rim will go out of true rapidly the wheel is built badly; and a good build requires good spokes. Spokes literally hold the whole item together. Sapim define a spoke as, ‘being the link between the hub and the rim’. Spokes enable wheels to have remarkable strength with surprisingly little weight.
We use exclusively Sapim spokes. Sapim only make spokes and nipples. They offer a big range products, allowing for an excellent option any wheel. We have no concerns about the quality of DT Swiss spokes; there are a small number of subtle difference between them, however the Sapim range delivers a better solution for good value, high performance wheels that last for many years. We offer almost the entire Sapim stainless spoke range. We do not offer their more basic range. Sapim have a permanent research centre so despite being established in 1908, they are still continuing to innovate and keep up with market developments. All Sapim spokes are made in either Belgium or France.
Different spoke profile types
There are three spoke types when it comes to their profile construction. The plain gauge spoke, the butted spoke and the aero spoke – an aero spoke in itself may or may not be butted as well. The plain gauge spoke is the basic spoke used in the vast majority of wheels. There are two versions that Sapim makes; the Zinc spoke and the Leader spoke. The Zinc spoke is the most basic version and is quite simply a cheap spoke. If you want a spoke which lasts and you want one which works well in conjunction with alloy nipples, a stainless spoke is required – especially in the UK where our weather conditions can be very harsh on components. So for this reason, their Leader spoke is a good economical spoke for economical but durability focused wheels. There is a big variety in plain gauge spokes, although you may be unable to tell this by eye. Sapim’s leader spokes receive the same strengthening treatments as their butted spokes, which means they have a lot more strength than most competing versions. They are also still made from stainless steel. The main disadvantages of the Leader spoke over other Sapim spokes are weight, comfort and fatigue life. The Leader is still only really a basic spoke, best suited to economical wheelsets. They are available in a range of profiles so they can be applicable for builds which require unusually large spokes. They also offer a huge range of lengths which can be modified if necessary. We have a couple of spoke cutting/rolling machines which allow us to produce Leader spokes down to 70mm.
A spoke is subject to three key kinds of force. One is constant, because of the tension it is held under and the weight of the bicycle. Sapim refer to this as carry. The others are inconstant (impact and transmission); when an impact is made upon the wheel so the spoke needs to help absorb these irregularities. The spoke will only do part of this, some will be absorbed by other components; rim, frame, handlebars etc. Some is passed onto the rider. It is when a wheel receives these sudden forces that butted and aero (which in the Sapim range are also butted) spokes become important. The dimensions of a butted spoke differ from plain gauge because they are not a continuous thickness throughout. Sapim’s butted spokes use the SCFT-system (Sapim Cold Forging Technology). This allows the spoke to be stretched without causing any damage to its molecular structure and Sapim claim this increases the strength in the central portion by at least 48%. Butted spokes can flex and absorb impacts better than plain gauge because their central butting allows them to stretch. The extra material around the elbow and nipple allow strength to be retained in the areas that commonly fail. Finally the thinner central portion allows the butted spoke to be lighter than the plain gauge.
With the Sapim Spoke range, the most basic butted spoke is the Strong. The Strong spoke is only one step up from the Leader spoke. It is 2mm throughout except for its spoke elbow where it is 2.3mm. So it is like a Leader with an extra thick elbow. For this reason we can also cut these down to 70mm easily. They are stronger than the Leader but no more comfortable and actually a little heavier.
Sapim’s most common double butted spokes are called Race spokes. This is equivalent to DT Swiss’ Competition spokes. They are 2.0mm thick both ends and 1.8mm thick in the central section. This became over time the standard choice for most wheels. They are good for MTB, standard touring, standard road use. However, if you are looking for a more exotic double butted spoke. Sapim offer a number of other types.
Firstly there is the Laser spoke. This has been made out of a different type of stainless steel. It was developed in response to a growing need for high tension spokes. Higher tensions make a wheel stronger, stiffer and more stable. The Laser also has a thinner central portion as it is butted in a 2.0mm-1.5mm-2.0mm profile. The 2.0mm elbow and nipple end make the spoke compatible with the same hubs as the Race and the same nipples too. They both come with nickel coated brass nipples as standard. The Laser spoke is only slightly more expensive than the Race so it can be an easy upgrade on light weight road wheels. They are not designed for heavy duty applications. They are not recommended for particularly high transmission applications. They are also much twistier than Race when building with them or any subsequent truing. So the Laser spoke is, while a light spoke, not a good choice for a wheel that is to be used long term. It can be a good option for an event wheel or a junior wheel where weight is a major factor and so is keeping costs down.
Secondly there is the D-Light spoke. The D-light spoke can be unpopular as a spoke because it is the only spoke of the Sapim range which cannot be trimmed or cut/rolled from blanks for builders with spoke machines. It is nevertheless a spoke we carry in a broad range of lengths because it is a far more carefully optimised spoke than the Laser and Race. It is a step up in sophistication and becomes a far better choice than the Laser for performance applications which are there to be used long term.
The Laser spoke has been rated as not suitable for use with disc brakes. However, the Race spoke is relatively heavy for a double butted spoke. The D-Light compromises between the weight saving of the Laser spoke and the strength advantages of the Race spoke. The D-Light is butted in a 2.0-1.65-2.0mm profile, making it compatible with the same hubs and nipples as the Race and Laser spokes. Moreover, the butting either end is shorter than normal, the butting at the elbow is a bit shorter, at the threads end, the butting only covers the thread. So this profile keep the centre of the spoke thicker to prevent twist whilst re-inforcing the extremities for strength. As a result the weight/spoke is closer to the Laser, the comfort and weight better than the Race but the range of suitable applications far greater than the Laser.
The D-light is a lighter weight, lighter duty and more performance focused spoke than the Race. The Sapim Force in contrast goes the other way. The Force is no longer a double butted spoke but a triple butted spoke. It is 2mm at the threads to allow full compatibility with standard nipples. It is 1.8mm in the central portion like the Race and then 2.2mm thick at the elbow. Sapim realised that the weakest point on their spokes was the elbow rather than the threads, so re-inforcing this area provided greater strength/resilience. It makes the Force slightly heavier than the Race but a lot tougher and a lot more durable.
Finally there is the super spoke which was developed by Sapim in collaboration with Tune. The idea was to create a stainless steel spoke that was strong, yet lighter than any other produced before. The butting profile is extremely light gauge 1.8-1.4-1.8mm. This allows the weigh to be a mere 231g (64 pieces at 260mm). Their profile will cause some compatibility issues with some hubs as well as requiring different nipples. They are made from a different stainless steel which Sapim are being secretive about. This exotic steel accounts for their exceptionally high cost. They are available only as a special order item. The super spoke is actually a poor double butted spoke choice for almost all wheels. While the intentions were good with this spoke, it is so prone to twist that it lacks the resilience required for most wheels. It should be thought of very much as an event only spoke and better suited only to stiffer components. We do not recommend or stock this spoke.
Sapim also produce a range of Aero spokes. Aero spokes are made from butted spokes so they still offer all the butted spoke benefits. In addition to this they offer aerodynamic advantages. The process of making them aero improves their fatigue life and strength. They can also be steadied during building which helps to prevent spoke twist.
The most famous aero spoke produced by Sapim is called the CX-ray. It is 2.0mm at the elbow, the centre section is oval and is 2.3mm deep but only 0.9mm wide. The CX-ray was developed from the Laser spoke. They have hammered it into an aero profile. The profile allows for compatibility with almost all hub types and standard nipples. One disadvantage of previous ‘bladed’ spokes is that they often required hub filing. This was not only tedious but also weakened the hub. Some hubs came pre-filed but this limits choices for builds, now bladed spokes have now fallen out of fashion in favour of aero spokes. The CX-rays are so strong that they are even rated as suitable for downhill racing. We stock CX-Rays in both J bend and Straight pull variations. We never recommend the use of straight pull hub design with a round spoke – if too much friction is present between the spoke and nipple and insufficient at the hub, the spoke will endlessly revolve rather than being able to be adjusted. However, with an aero spoke this can be held steady and long term fine tuning is still possible.
Sapim also produce the CX-Sprint spoke. The CX-Sprint we only stock in black (unlike all the other spokes previously mentioned). Like the CX-Ray we carry it in J bend and Straight pull. The CX-Sprint is very similar to the CX-Ray but slightly heavier and slightly thicker in the central portion. The spoke was developed for those looking for a stiffer spoke than the CX-Ray. Most applications of the CX-Ray are alongside stiff rims and hubs, however sometimes particularly powerful riders appreciate greater stiffness especially in the rear wheel. For this reason, CX-Sprint spokes either throughout at the back or on the drive side rear will increase stiffness here. It does come with a comfort penalty as well as weight penalty and the spoke is not as durable as the CX-Ray, so it is only an advantage principally for those looking for maximum stiffness.
The CX-Delta spoke is the last CX (aero) spoke that we stock from Sapim. We introduced it to give us a price point between the CX-Ray and the Sapim D-light. Pillar offer a range of more economical spokes than Sapim which are produced to a lower standard. We do not offer Pillar spokes because we put a lifetime warranty on our builds and this requires us to use spokes which can rely on long term. However, one of the economies found by Pillar with their ‘aero’ spokes is that the spokes are simply a flat profile – like a ruler, rather than aero like a wing. It is a much more economical way of flattening a spoke and Sapim responded by introducing their equivalent – the CX-Delta. We would always rather use the higher end and far more elegant CX-Ray, however the CX-Delta is nevertheless a nice upgrade over the D-light spoke.
Finally Sapim have produced the CX Super spoke. This is an aero spoke which starts off in life as a Super spoke. It is a far better choice than the Super spoke which we would say has no sensible real world application, however even the CX-Super’s range of suitable applications is very limited. It is a weight weenie spoke – it shaves around 40g off of a wheelset verses the CX-Ray and it is still a strong and durable spoke. However, despite its strength and durability, it is fragile, it is easily damaged during building or other contact and it is notably more flexy than the CX-Ray – we do not recommend the spoke and do not stock it, however we can offer it via special order if anyone would particularly like it to be used in their wheels.
Below is a chart which compares spoke weight/spoke:
|Spoke type||Weight per spoke @ 285mm|
Below is a chart with a technical comparison of Sapim spokes:
|Type||Weight (x64@260mm)||Strength||Fatique life (revolutions)|
|CX||423g||1200n/mm2||To be announced|
|Super spoke||231g||To be announced||To be announced|
|CX Super||To be announced||To be announced||To be announced|
It is important to understand that the strength measure is not an overall strength comparison; it is a comparison of the strength of the central portion. The central portions on certain spokes are slimmer which makes them look disproportionately strong. The Strong spoke is considerably stronger than the Laser despite appearing weaker in this comparison.
Front wheels and lacing patterns
When selecting spokes for a wheelset it is important to understand each wheel differently. The front wheel carries less stress than the rear. Therefore it does not need as strong spokes and fewer spokes are required. Sapim Race spokes are appropriate for most front wheels, although Sapim Lasers could be used if weight saving was important or better still CX-rays. A front wheel can normally be both radially or tangentially laced. This means the spokes can either come directly out of the hub to the rim, or they can come out at tangents to the hub. Tangential spokes normally cross three other spokes before they reach the rim. This has given rise to the term 3X, which is the most common lacing pattern. Many hub manufacturers refuse to warranty products built into radial wheels. There have been instances where the spoke has been pulled straight through the hub flange.
Many wheel builders refuse to build wheels with radial lacing patterns because of the risk of the spoke being pulled through the flange of the hub. However many major wheel manufacturers have moved towards radial front wheels because of aesthetic benefits as well as some weight saving advantages. I have built many wheels with radially laced spokes and none have ever failed at the hub. However, I always point out before building that with the majority of manufacturers, radial lacing invalidates the warranty. I would also discourage the use of radial lacing unless the hub has been specifically designed for it because it distorts the hubs making for a weaker wheel and it makes for a slightly rougher ride. Another factor in radial lacing is it is a stiffer lacing pattern. This is why most performance wheels now use radial lacing on front wheels. There are two ways you can lace radially. One is heads in, the other is heads out. The spoke can be laced in either orientation. Heads in is stiffer which puts greater strain on the spoke and hub flange. Some manufacturers that allow for radial lacing on the front do so only if laced with heads out. If you are lacing radially for aesthetic reasons, it is best to have heads out. This will offer a more comfortable ride and a stronger build. If you are looking for maximum stiffness and the hub will allow it, lace heads in.
Dishing and rear wheels
A rear wheel is quite different to a front. It is normally ‘dished’, it also carries a higher proportion of the bike’s load. It cannot be completely radially laced because a rear wheel has turning forces exerted upon it from the hub, these would stress and break the hub flange as the spokes are pulled out. Most commonly rear wheels are 3X, however 40 spoke wheels are done in a 4x lacing pattern. Higher spoke counts still require high cross counts in order to maintain the spoke angle. Other wheels which require particularly short spokes such as Brompton or Rohloff wheels require 1x or 2x. Lower spoke counts necessitate lower cross counts 24 spokes or less requires 2x as 3x would provide compromising angles at the rim as well as the potential for spoke heads to come into contact with other spokes. It is possible to radially lace on the non-drive side of the rear wheel in some instances (not when using disc brakes). This will improve stiffness but again hub manufacturers normally prefer you not to.
Dishing occurs on rear wheels which uneven centre to flange measurements, normally there to incorporate external gears. The right hand flange is moved towards the centre line of the hub in order to fit in the cassette or freewheel. This means that the right hand or ‘drive side’ spokes need to be under greater tension than the left hand or ‘non-drive side’ spokes. The tensions on a drive side are sometimes as much as triple that as on the non-drive side. Wheelbuilders and manufacturers have been creative in their solutions to this problem.
Sometimes people opt for twice as many spokes on the drive side; however quality rims normally have an allocated direction so this can be an inappropriate solution with spokes facing the wrong way in the rim. Moreover this solution requires a stiff rim to remain true; two successive spokes pulling in a given direction separated by only one in the opposing direction makes for a natural waver in the rim. Another solution which I sometimes use is to have different spokes on the drive side to the non-drive side. The non-drive side will commonly use the same spokes as used on the front wheel. The drive side will have heavier duty spokes and importantly spokes with less flex. This means that the spokes flex more evenly on both drive side and non-drive side. A light duty build could use Sapim Laser spokes for the front and non-drive side and Sapim Race for the drive side. Heavier duty could be Sapim Race for front and non-drive side and Sapim Strong for the drive side. You could also use D-Light spokes with Race spokes or Laser spokes to achieve similar slightly varying results. Many wheelbuilders neglect such detail, although it is important for a well balanced wheel. Moreover it does not need to add considerably to the cost of the build. An important factor to consider before doing this is that sometimes a larger spoke elbow (such as the Strong spoke) will sit badly in a hub. Considering the quality of all Sapim spokes, most wheelsets can be laced with the same spokes throughout.Dishing and front disc wheels
A front disc brake wheel behaves much the same as a rear rim brake does. There is torsional forces coming from the hub and dish is introduced because of the rotor. For this reason, we generally encourage that disc brake wheels use the same number of spokes front/rear. However if you are going to drop spoke count down on one of the wheels, the front is still the obvious choice as it carries less actual weight.
Spoke application choice
Below is a format modified comparison of the Sapim spoke range made by Sapim:
|Usage||Light (<70kgs)||Medium (<85kgs)||Heavy (>85kgs)||Very heavy load (tandems, ebikes, …)|
|Weak rim||Low||All spokes||All spokes||All but Laser||Strong|
|Medium||All spokes||All but Laser||All but Laser||Strong|
|Heavy||All spokes||All but Laser||All but Laser||Strong|
|Competition (road, MTB)||D-Light, Laser, CX-ray||D-Light, CX-ray||D-Light, CX-Ray||–|
|Professional||Laser, CX-ray, Super Spoke, CX Super||CX-ray, Super Spoke, CX Super||–|
|Stiff rim||Low||All spokes||All spokes||All spokes||Strong|
|Medium||All spokes||All spokes||All spokes||Strong|
|Heavy||All spokes||All spokes||All but Laser||Strong|
|Competition (road, MTB)||Laser, CX-ray||Laser, CX-ray||Laser, CX-ray||–|
|Professional||Laser, CX-ray, Super Spoke, CX Super||Laser, CX-ray, Super Spoke, CX Super||Laser, CX-ray, Super Spoke, CX Super||–|
Sapim are, I feel, a little harsh on the Laser in this analysis. They have acknowledged to me that it is a high strength spoke. Stronger, they claim than the DT Swiss Revolution spoke which has been rated as capable of withstanding more than the Laser here. However, the problem with the Laser is how prone it is to spoke twist, more so than the Revolution. If the spoke becomes excessively twisting during building or retruing, that will weaken the spoke considerably. This is why the CX-ray, despite being made from the same material and drawing process, is rated as capable of so much more. Holding the spoke steady prevents spoke twist.
If you are interested in learning more about choosing wheelsets, building wheels and selecting component parts as well as information on repairing wheels please seeBicycle Wheelbuilding: The Manual an ebook which is available exclusively through DCR Wheels.