Best Upgrades for the New Specialized Tarmac SL9

The Tarmac SL9 arrives with serious stock equipment: Roval Rapide CLX III wheels, a Roval Rapide integrated cockpit, S-Works Power with Mirror saddle and the new S-Works Rapide seatpost.

None of that is bad. In fact, it is very good. But top of the range from the factory is not the same as top of the range when the bike is built properly. For riders who care about weight, detail, individuality and the final feel of the bike, there is still plenty of room to make the SL9 better.

1. Schmolke TLO 50 Wheels

The stock Roval Rapide CLX III wheels are fast. Schmolke TLO 50 wheels are the world's best kept secret in road wheels.

This is where the SL9 build gets serious. The new Tarmac is built around aero efficiency, low weight and all-round race speed. Schmolke TLO 50s take that same idea and push it harder.

A 50mm-deep aero disc wheelset that can come in around 940g is not normal. That is the whole point. You get proper aero depth without dragging around the weight that usually comes with deep wheels.

Roval Rapide CLX III wheels are good. Schmolke TLO 50s are for the rider who looks at a $20K+ bike and still sees the biggest upgrade sitting right in front of them.

If you want the SL9 to feel properly outrageous, start with the wheels. Schmolke TLO 50s are the upgrade most riders will not see coming, until they try to follow you up the road.

2. Gelu Carbon Saddles

The stock S-Works Power with Mirror is a premium saddle. A Gelu K-Series carbon saddle is a different kind of upgrade.

Gelu is for the rider who wants the SL9 to look and feel less like a catalogue build. The headline option is the Gelu K3, listed at approx. 38g, but the real appeal is not only the number on the scale.

A Gelu saddle gives you a lighter bike, a cleaner custom look and a handmade carbon part that suits the kind of rider who has already gone all-in on the latest S-Works frame.

For the lightest possible SL9 build, Gelu is the saddle conversation. For the rider who wants the bike to look more personal, it is also one of the most visible upgrades on the whole bike.

3. Alpitude Gardena Saddle

Alpitude Gardena is one of the true up and coming boutique carbon saddle options.

Alpitude is a specialist Italian carbon manufacturer building the kind of lightweight parts that belong on premium custom bikes. It is not a mass-market saddle brand pretending to be special. It is boutique, handmade and increasingly trusted by riders who want something better than standard.

That makes the Gardena a natural match for the SL9. You are already starting with one of the most advanced race frames available. A handmade Alpitude saddle gives the bike a more refined, more personal and more complete finish.

This is not about turning the bike into a science project. It is about removing weight from a very visible part of the bike and giving the whole build a more special feel.

If Gelu is the extreme weight and customisation option, Alpitude is the refined boutique carbon option. Both make sense on an SL9. The better choice depends on the rider, the saddle shape and the final look of the build.

4. Darimo SL9 Seatpost from approx. 109g

The SL9’s new seatpost is already more aerodynamic than the old platform. The Darimo carbon seatpost for the Specialized S-Works Tarmac SL9 takes the build in a more weight-focused direction.

Darimo SL9 seatposts start from approx. 109g in 300mm length, giving SL9 owners a serious handmade carbon alternative to the stock S-Works Rapide post.

The sensible angle here is not pretending the stock S-Works post is poor. It is not. The angle is that a Darimo post gives the build a lighter, more specialised and more boutique finish.

For riders who want the SL9 to feel less like everyone else’s SL9, the seatpost is one of the cleanest upgrades to look at.

5. Darimo Nexum Drag Integrated Cockpit

The stock Roval Rapide integrated cockpit is already serious. The Darimo Nexum Drag integrated cockpit is for riders who want to take the front end further.

A Darimo Nexum Drag cockpit gives you a lighter, cleaner and more custom front end. It is the upgrade for riders who want the fit, finish and weight of the cockpit to match the level of the frame.

With custom fit options, internal cable routing and a listed weight around 226g, the Nexum Drag turns the front of the bike into something more deliberate. Less factory. More finished.

For an SL9, the cockpit is the finishing piece. Get the size, shape and routing right, and the whole bike feels more complete.

Factory superbike vs finished superbike

The Tarmac SL9 is not a bike that needs rescuing. It is already one of the most advanced road bikes available.

But there is a difference between buying the top factory build and creating a bike that feels truly finished.

Schmolke, Gelu, Alpitude and Darimo are the upgrades for riders who want their SL9 to be lighter, sharper, rarer and more personal than the one sitting on the showroom floor.