Trying to decide whether the Trek Emonda or the Specialized SL7 Tarmac is better for you? Read for a detailed comparison of the geometry, design, and components of these two premium, lightweight carbon fiber bikes so you can find out which one suits your riding style and preference.
Similarities Between the Specialized Tarmac SL7 and the Trek Emonda
Let’s start with what these two racing bikes have in common—after all, they’re designed to fit the same all-around performance-oriented road bike market niche.
The Tarmac SL7 and the Trek Emonda are both manufactured in Taiwan for the American companies Trek and Specialized, so you can expect a similar build quality between the two. They are both manufactured in Giant’s factory, in fact.
Both the Tarmac SL7 and the Trek Emonda are outfitted with disc brakes and have no rim brake options. This is typical of modern road bikes. Since these bikes are at the higher end of the market in terms of price, disc brakes’ increased cost won’t add much to the already high price tag.
Both bike frames are available in two levels of carbon layup. The highest-grade carbon options for both the Tarmac SL7 (Fact 12r carbon) and the Trek Emonda (OCLV 800) are about the same weight—but the Emonda SLR is ever slightly lighter. The lower-grade Tarmac SL7 (Fact 10r carbon) is lighter than Emonda’s lower-grade carbon frame (OCLV 500).
The two bikes’ maximum tire width is also nearly the same, with the Emonda’s official tire rating coming in at 28 mm and the Tarmac’s at 30 mm. Unofficially, both the Emonda’s and the SL7’s wheels can accommodate up to 32 mm tires with at least 2 mm of tire clearances on each side, so the maximum tire widths between the two bikes are virtually the same.
Tarmac SL7 vs Emonda: Frame Geometry
The geometries of the Tarmac SL7 and Emonda are true to a road racing bike design, being longer and lower to the ground on the front end, with a short wheelbase.
The Emonda has a more comfortable geometry than the Tarmac SL7, with a higher stack and lower reach. However, its RSL integrated barstem handlebar has a longer total reach at 100 mm, 25 mm more than the SL7’s Roval Rapide handlebar at 75 mm.
If you compare the two bikes in the same frame and handlebar/stem size, the Emonda’s frame and handlebar together come out a bit longer than the SL7’s—9 mm to be exact.
The Emonda offers one more frame size option than the SL7, offering eight sizes to the SL7’s seven frame size choices. However, the SL7 frame is available in smaller sizes than the Emonda frame, making it a better choice for shorter cyclists.
The distance between the two wheel centers or wheelbase is roughly the same between the two bikes, and so is the trail measurement. This means that the SL7 and the Emonda handle in roughly the same manner—they both feel agile and aggressive.
Bottom Bracket Comparison
While both bikes use press fit bottom brackets in the last generation, this generation’s Specialized Tarmac SL7 and the Trek Emonda both use threaded bottom brackets.
In theory, press-fit bottom brackets are lighter and stiffer than threaded ones. But in practice, threaded bottom brackets have gained favor among cyclists over press-fitted ones because press-fitted bottom brackets often become loose inside the frame’s housing, making a telltale creaking sound.
The two bikes use different standardized threaded bottom brackets: the Emonda has a T47 bottom bracket, while the SL7 has a BSA bottom bracket.
T47 bottom brackets have a larger diameter than BSA, so Emonda’s frame has a larger housing. The T47 threaded housing has its bearings inside the bike frame, while the BSA has external bearings. This means that the T47 bearings are held more stiffly in the carbon frame housing because of its internal bearings.
When buying a new crank or spindle set, make sure that its diameter and length are compatible with the T47 or BSA housing on your SL7 or Emonda bike. Both the T47 and BSA housing are compatible with mainstream spindle and crank measurements.
Tarmac SL7 vs Emonda Complete Bike Components
Here’s a side-by-side comparison of the components each of these bikes will have if you buy a pre-built Emonda or Tarmac SL7.
The Emonda comes with a Bontranger Aeolus RSL integrated barstem, while a Roval Rapide two-piece handlebar set comes with the SL7. The Emonda’s one-piece, integrated barstem has a cleaner, sleeker look, and is lighter than the Roval Rapide handlebar set. On the other hand, a two-piece handlebar and stem set allows for more customization of your handlebar rotation angle setup.
Both the Emonda and the SL7 use proprietary Trek and Specialized seatposts respectively. The Specialized seatpost is D-shaped, while the Trek seat mast cap is round.
The D-shaped seatpost should, in theory, make the SL7 a more comfortable ride. In reality, SL7 is stiffer and harsher than the Emonda.
There’s no real difference between the two bikes here. You can outfit either one with a Shimano groupset or an SRAM groupset. The only main difference here is that you can’t buy the Tarmac SL7 S-Works bike equipped with lower-level groupsets like SRAM Force and Shimano Ultegra. You need to buy a frameset and customize the components by yourself for that.
The Tarmac SL7’s Roval Rapide is only available in one size (51 mm front depth, 60 mm rear depth) compared to the Emonda’s Bontrager Aeolus which is available in four sizes of rim depth (37 mm, 51 mm, 62 mm, and 75 mm).
That said, depending on the bike shop where you buy the Tarmac, they might allow you to swap the Roval Rapide with a much shallower Roval Alpinist (33 mm depth) if you prefer it.
The Specialized Tarmac SL7 comes fitted with Turbo or Turbo Cotton tires, while the Trek Emonda comes with the Bontranger R3 or R4 tire. The Turbo and Turbo Cotton tires have a lower rolling resistance than the Bontranger R3 and R4 respectively. The lower rolling resistance leads to less energy loss as the tire moves along, making you faster. However, the Bontranger R3 and R4 tires are more durable and long-lasting than Turbos which are known to be very fragile.
The Emonda and the SL7 are both racing bikes. True to this purpose, they’re equipped with short, snub-nose saddles that put the rider in an aerodynamic position angled forward towards the ground. The Emonda uses the Bontranger Aeolus saddle and the SL7 uses the Specialized Power saddle. Both saddles are very popular on the market.
Tarmac SL7 vs Emonda Paint Job
The paint job you choose to put on your bike is, of course, a personal choice that doesn’t affect performance.
That said, if you’re dead set on a certain color for your bike or if you value your bike’s looks highly, the Trek Project One program has far more customization options than the Specialized bike brand has on offer. Color personalization from Trek Project One does come at a higher cost.
Personalizing your bike may not have anything to do with performance, but it can be one of the most fun aspects of riding—it feels great to show off a cool, tricked-out bike to your riding buddies.
Another notable difference is the side logo on the highest-grade Tarmac SL7 frame that reads “S-Works” vs the lower-grade Tarmac SL7 which has the normal “Specialized” text. This is a little dirty trick by Specialized to differentiate their highest-grade carbon even though they share the same shape.
The fact is that these bikes have very similar geometry, so their ride feel is quite similar too. If you select the same handlebar and stem dimensions on both bikes, they feel virtually the same to ride.
The Emonda and the Tarmac SL7 are meant to be lightweight, maneuverable, and fast with a reasonably high aerodynamic performance. They make tough climbs easier and offer stability and safety on fast descents.
Since they both use threaded frames to hold the bracket in place, they both lack stiffness in that area. Press-fitted frames like the Cannondale SuperSix EVO and the Giant TCR outcompete the Emonda and SL7 in this aspect. Between the SL7 and the Emonda, the SL7 feels stiffer during pedaling when the same crankset is installed.
Overall, neither the Emonda nor the SL7 shine in terms of the comfort on the front end. However, the SL7 has a beefier stem handlebar setup, making it better for sprinting than the Emonda. In another win for the SL7, the Emonda’s lighter barstem transfers more vibrations from uneven terrain, making it less comfortable on a rough road surface.
The SL7’s D-shaped seatpost is theoretically stiffer during the side-to-side motion that cyclists do during pedaling out of the saddle. The D-shaped design is also meant to increase comfort on rough riding surfaces. In reality, while the SL7 does feel stiffer than the Emonda the Emonda’s back-end is more comfortable.
Which is the Better Bike?
Both the Trek Emonda and the Specialized Tarmac SL7 offer superior performance, responsive handling, and low weight. The bikes are so similar that the choice between them comes down to which one is a better fit for your body.
The frame geometry of the Emonda is better for riders who need a higher and shorter front end (though, you shouldn’t get the Bontrager RSL integrated handlebars), while the Tarmac SL7’s frame is lower down on the front end. The lower front on the SL7 means that many riders will need to add spacers below the stem so they can get a comparable stack height with the Emonda.
The performance difference between the two bikes skews slightly in favor of the SL7. If you’re absolutely set on the most aggressive, stiff, high-performance bike, the SL7 is better suited to your needs. If you’re comfortable with sacrificing a tad of performance for the sake of comfort, the Emonda may be the way to go for you.
The Project One Program from Trek gives the Emonda a clear advantage over the SL7 in customization options. Through Project One, Trek gives riders control of almost every aspect of their bike, offering a wide range of colors and letting them choose almost every component.
The Emonda SLR, a high-grade, lightweight, composite frame, is lighter than Specialized’s high-grade S-Works frame, giving Trek a slight edge in high-end frame choice. If you’re after a low-cost frame, however, Specialized has a lighter low-grade frame. The low-grade Emonda SL frame is heavier than the corresponding low-grade Tarmac SL7 frame.
The overall appearance of both bikes will appeal more or less to different riders’ tastes, and the differences between the two are slight enough that personal taste is a fine basis to make your choice. Both of these bikes are excellent for road cyclists and are great examples of modern bike design. Whichever choice you make, you won’t end up dissatisfied.