Headset Cable Routing: End of the World, or Not as Bad as We Thought?

Headset cable routing is the hottest MTB tech to hate right now, but is there merit to the design? We reached out to some bike brands to find out.
This might be some of the cleanest cable routing ever. Photo: Sam James

Bike manufacturers are always finding new ways to innovate and improve the modern mountain bike and right now one of the hottest things to hate is headset cable routing. Many brands these days are focusing on integration, with cables moving from the outside to the inside of the frame, hidden bearings, and a cleaner design overall.

It makes sense that once a great formula for an amazing bike has been found, it should be cleaned up aesthetically. Looking at something like the automotive industry, the cycling world appears behind in some regards. Taking cues from road cycling where cables and hoses have been finding their way through handlebars in recent years, and stems and headsets are decreasingly visible, some mountain bike manufacturers are now routing hoses and cables through the headset as the entry point to the frame rather than either side of the headtube.

While fully integrated cabling is generally well-received on road bikes, the move to route cables and hoses through headsets on mountain bikes is a contentious one, perhaps because mountain bikers on the whole tend to be more hands-on with their maintenance. After all, mountain bikes tend to require more maintenance than road bikes. Running hoses through headsets introduces extra complexity and steps when maintaining the bike. For example, a full headset overhaul would require disconnecting the brake hose and bleeding it. It also means more proprietary parts to guide the hoses through the headset and into the frame.

While some mountain bikers are still proponents of fully external cabling and always will be, like it or not, these changes are coming. So, I reached out to a handful of brands spearheading this campaign to figure out what this means for the average rider. Why did they choose to go in this direction, and is it truly is the end of the world as we know it?

Looks aren’t everything

Aesthetics are undoubtedly one of the driving factors behind headset cable routing, but as it turns out there are other benefits too.

“Less holes in the frame results in a stronger and even lighter frame,” said Maria Benson, Director of Product Management at Cervelo. Benson also said “it’s a more simple design, which improves manufacturing efficiency. Fewer holes also reduces the incidence of water/dirt ingress into the frame.”

Michael Wilkens, International PR Manager at Merida echoed the sentiment of fewer holes making a stronger frame around the critical headtube area, and added the fact that shorter cable loops means fewer opportunities for snagging.

Circling back to the aesthetic argument for headset cable routing, integration makes a bike look more like a finished package, bringing a more professional look and importantly, is more appealing to the end user. There are, after all, entire industries based on the aesthetics of consumer products; it makes a huge difference to the general reception of a product and often can be the difference between a consumer buying one brand over another.

Julian Wagner, Bike Marketing Lead at Scott Sports SA, said that for them it’s about figuring out how they can make Scott bikes stand out to the consumer on the showroom floor. Wilkens also weighed in on appearance; “even though most would deny that they buy a mountain bike just based on aesthetics, this definitely has a subconscious influence on the purchase decision.”

Wilkens also said Merida had conducted surveys amongst their distributors and dealers and the results clearly showed that “they also prefer cable routing through the headset of mountain bikes.” He elaborated that the customer feedback to these distributors and dealers has proven that “the bikes sell better in the shop this way.”

It certainly is tough to deny the simple elegance of the ZHT-5. Photo: Sam James

An additional point in favor of headset cable routing is that the cable entry point at the headset means for folks like myself that run their brakes ‘moto’ style the routing is much tidier than on a carbon tube-in-tube bike where the entry for the rear brake is on the left side of the headtube. When the hoses are routed this way it means the brake hose not only makes an unsightly loop but also tends to rub on the headtube. It’s a small thing but to me is a huge oversight for a large portion of the market that’s seen on some of the biggest brands like Santa Cruz, Rocky Mountain, and Ibis.

Since most brands seemed to have developed headset routing on road bikes before rolling it out to their mountain bikes, I wanted to know what the brands learned along the way. Wilkens told me Merida had in fact started with their cross-country bikes. They found that longer travel forks created greater challenges, which led them to develop a new version of the headset for the ONE-SIXTY that is “significantly less sensitive to creaking thanks to a plastic split ring, which uses more durable bearings and is more service-friendly thanks to the two-piece design” seen here.

Does headset routing make maintenance harder?

Of course, the main objection to headset cable routing is serviceability. With the added complication and mountain bikes needing more frequent servicing than road bikes, I posed the question of how designers had mitigated these problems. Wilkens told me that Merida had worked with Acros to spec higher quality bearings and additional sealing throughout the headset to prevent water/dirt ingress. He and Benson from Cervelo also mentioned that the companies had produced documentation to guide the users through the task of servicing the headset.

As far as replacing the headset bearings, Wilkens, Benson and Wagner all said that while the headset designs are proprietary, they have been designed so that the brake compression nut fits through the opening in the headset top cover without needing to cut the wider barb and olive off, as some road bikes require for a simple headset maintenance job. On the Cervelo ZHT-5 for example, the only extra step is a brake bleed since it doesn’t have a dropper post and utilizes SRAM’s AXS wireless shifting. Scott actually used fewer plastic proprietary parts as a result of having fewer cable ports on the frame.

On a bike with mechanically-operated shifting and dropper post, a headset service means that the inner cables would need to be replace also, however in normal conditions this job shouldn’t need to be done more than once a year, at which point it would be polite to replace your shift and dropper cables at the same time. It’s also worth noting that replacing the lower headset bearing does not require the removal of any hoses or cables and is business as usual. Greasing the upper bearing on most of these systems can be achieved simply by removing the stem and spacers and sliding the top cover out of the way to access the bearing.

Can you spot the hose? Photo: Sam James

As far as cable routing goes, all of the representatives we spoke with said that running cables is actually easier on these bikes since the cables can be run from the bottom of the frame up to the top, and the headtube opening provides such a large opening that it doesn’t require any fishing for cables or use of special tools to get the cables where you need them. Also in the case of aluminum frames with no internal guiding this makes it a lot easier, and gives lots of space to slide any necessary sound deadening such as foam sleeves over the hoses, which can be trickier when working with a small opening.

Are we in for more integration?

As I spoke with all of them, toward the end I wondered if they see even further integration on mountain bikes. Wilkens said Merida has no plans for it, clarifying that “We see the current solution as an ideal compromise between integration and interchangeability.” Wagner was more tight-lipped.

“We’re always discussing new ideas here at SCOTT, but not all new ideas turn into reality,” he said. “I think everything has its limits, but are we close to that limit?”

Benson said Cervelo wants to pursue the concept of integration further, but that the key to this lies with the component manufacturers.

I began my research for this piece I was very much of the opinion that aside from high end XC race bikes, headset cable routing has no place on a mountain bike. As a bike mechanic, an additional brake bleed or cable replacement is not daunting, but anything that makes bikes easier to work on is welcome.

I appreciate where the modern mountain bike is at right now. They’re things of beauty, but I’m not sure if ease of servicing is something I want to sacrifice given how frequently I tear down my personal bike. I am however open to smart, engineering-led solutions, and it seems that while headset cable routing does introduce some extra complexities, they might actually be worth the trade-off, if it means bikes can be stronger, lighter and prettier, especially as more components go wireless. For now I’m keeping an open mind and will wait to see how these bikes pan out in the long run before I pass judgement. Will they be surprisingly reliable and easy to service or, maintenance nightmares that cost a fortune in shop labor to keep running?