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TREK FX Review

Last updated: May 21, 2020

Category: Hybrid Bikes

In the FX and FX Sport ranges, Trek have built a hybrid bike befitting its all-rounder tag. It is a flat-barred commuter on one hand but with a spec sheet to tackle much longer, much more demanding riding – particularly at the top end of the range.

Overview

Trek dub the FX and FX Sport ranges as their ‘anywhere, anytime fitness bike’ as opposed to just being a commuting bike with a performance edge. Flat bars and a more relaxed, upright geometry point to its urban riding purpose but it would not look out of place on more characterful bike paths and longer, more varied rides.

Women’s version availableStagger (step-through) version availableGroupsetFrame materialFork materialBrake type
FX 1NoYesShimano AltusAluminumSteelRim, Disc version also available
FX 2YesYesShimano AceraAluminumAluminumHydraulic Disc
FX 3YesYesShimano AceraAluminumCarbonHydraulic Disc

As the name-change suggests, there is a dividing point in the range with the FX 1, FX 2 Disc, and FX 3 Disc more on the commuting side of the equation looking at their spec sheet. Even then, the difference between them is vast enough to make it worth serious consideration which is best for your needs.

Women’s version availableGroupsetFrame materialFork materialBrake type
FX Sport 4YesShimano TiagraAluminumCarbonHydraulic Disc
FX Sport Carbon 4NoShimano GRX 800CarbonCarbonHydraulic Disc
FX Sport 5YesShimano TiagraCarbonCarbonHydraulic Disc
FX Sport 6NoShimano 105CarbonCarbonHydraulic Disc

At the top-end, however, those with the FX Sport moniker throw in Shimano’s mid-range road groupsets and a carbon frame. The subsequent range of gears, smooth shifting, and compliant ride is deserving of something sportier than just the commute. Performance levels are right at the top of what you would expect from a flat-barred bike; a mid-point for riders using two wheels for more than commuting but not yet ready for, or requiring, a fully-fledged road bike.

Frameset

Starting with the entry-level FX range, the FX 1, FX 2 Disc and FX 3 Disc are all built around an Alpha Gold Aluminum frame. Alpha Aluminum is Trek’s innovative aluminum lay-up, which has been built to offer more compliance without reducing the stiffness-to-weight and affordability favored in alloy frames. Alpha Gold sits between Alpha Silver and Alpha Platinum, with the end result supposed to reduce fatigue over longer distances. Sleek welding keeps looks sharp too, particularly as all frames in the range boast internal cable routing.

FrameFork
FX 1Alpha Gold Aluminum, rack & fender mounts, DuoTrap S compatible, cantilever brake mount, 135x5mm QRFX Steel, threadless steel steerer, rack mounts, cantilever brake mount, 405mm axle-to-crown, 5x100mm QR
FX 2Alpha Gold Aluminum, DuoTrap S compatible, internal cable routing, flat mount disc, rack & fender mounts, 135x5mm QRFX Alloy, flat mount disc, rack mounts, 405mm axle-to-crown, ThruSkew 5mm QR
FX 3Alpha Gold Aluminum, DuoTrap S compatible, internal cable routing, flat mount disc, rack & fender mounts, 135x5mm QRFX Carbon, rack and fender mounts, flat mount disc, 405mm axle-to-crown, ThruSkew 5mm QR
FX Sport 4200 Series Alpha Aluminum, DuoTrap S compatible, internal cable routing, flat mount disc, rack & fender mounts, 135x5mm QRFX Carbon, flat mount disc, hidden fender mounts, 405mm axle-to-crown, 100x12mm thru axle
FX Sport Carbon 4400 series OCLV carbon, IsoSpeed, internal routing, 3s chain keeper, DuoTrap S compatible, fender mounts, flat mount disc, 142x12mm thru axleFX Carbon, threadless alloy steerer, hidden fender mounts, flat mount disc, 405mm axle-to-crown, 100x12mm thru axle
FX Sport 5400 series OCLV carbon, IsoSpeed, internal routing, 3s chain keeper, DuoTrap S compatible, fender mounts, flat mount disc, 142x12mm thru axleFX Carbon, flat mount disc, hidden fender mounts, 405mm axle-to-crown, 100x12mm thru axle
FX Sport 6401 series OCLV carbon, IsoSpeed, internal routing, 3s chain keeper, DuoTrap S compatible, fender mounts, flat mount disc, 142x12mm thru axleFX Carbon, flat mount disc, hidden fender mounts, 405mm axle-to-crown, 100x12mm thru axle

The choice of forks varies as you climb the range though, with steel on the FX 1, alloy on the FX 2, and carbon thereafter, including the FX 3. If your target is predominantly commuting, carbon is unnecessary and the durability of the other two should take precedence. Carbon, however, improves the compliance through the front of the bike and serves up sharp handling and lightweight too.

On the FX Sport models, that carbon fork is paired with an Alpha Aluminum frame on the FX Sport 4 and an OCLV carbon frame on the FX Sport Carbon 4, FX Sport 5, and FX Sport 6. OCLV is Trek’s patented carbon lay-up process, which looks to improve the durability of its carbon frames. Other tech passed down from higher-end models includes the IsoSpeed decoupler. 

By allowing the seat tube to flex independently of the top tube, road buzz is smoothed significantly, without impacting on the bike’s rigidity and pedaling efficiency. Road racing legend Fabian Cancellara used IsoSpeed-equipped bikes to tackle the cobbles of Paris-Roubaix, so it should ramp comfort up to noticeable levels on anything the FX Sport is likely to tackle.

All frames in the range are DuoTrap compatible, allowing wireless integration with your bike computer or smartphone from a sensor in the chainstay. Trek have also looked to save time and maintenance with the 3S chain keeper. It is a very small touch, but a further testament to Trek’s attention to detail.

Groupset

The groupsets clearly highlight the expected usage of each model, with the FX 1, FX 2, and FX 3 all wearing components from Shimano’s entry-level urban ranges. Shimano Altus, Shimano Tourney, and Shimano Acera are combined, with the FX 1 and FX 2 featuring triple cranksets for more gear options. The FX 1 uses rim brakes – though a disc version is available – and other bikes in the series come with hydraulic discs.

FX 1FX 2FX 3
ShiftersShimano Altus EF500, 7 speedShimano Altus M310, 8 speedShimano Acera SL-M3010, 9 speed
Front DerailleurShimano Tourney TY510, 34.9mm clamp, top swing, dual pullShimano Tourney TY710, 34.9mm clamp, top swing, dual pullShimano Acera T3000, 34.9mm clamp, top swing,
Rear DerailleurShimano Altus M310Shimano Acera M360, long cageShimano Acera M3000, Shadow design, long cage
CranksetForged alloy, 48/38/28, chainguard, 170mm lengthForged alloy, 48/38/28, chainguard, 170mm lengthShimano MT210, 46/30, chainguard, 175mm length
BrakesTektro alloy linear-pullTektro HD-R280 hydraulic disc, flat mount, 160mm rotorShimano MT201 hydraulic disc, flat mount, 160mm rotor
CassetteSunRace MFM300 freewheel, 14-34, 7 speedShimano HG31, 11-32, 8 speedShimano HG200, 11-36, 9 speed
ChainKMC Z7KMC Z7KMC X9

Step up to the FX Sport range, however, and the components step up too. Both the FX Sport 4 and FX Sport 5 wear Shimano Tiagra and the FX Sport 6 features Shimano 105. The exception to the rule is the FX Sport Carbon 4, with Shimano’s gravel-specific GRX group to highlight its off-road capability. It further reiterates Trek’s claim of an ‘anywhere, anytime’ bike.

FX Sport 4FX Sport Carbon 4FX Sport 5FX Sport 6
ShiftersShimano Tiagra 4700, 10 speedShimano RS700, 11 speedShimano Tiagra 4700, 10 speedShimano RS700, 11 speed
Front DerailleurShimano Tiagra 4700, 34.9mm clamp, down swingN/AShimano Tiagra 4700, braze-onShimano 105 R7000, braze-on
Rear DerailleurShimano Tiagra 4700, medium cageShimano GRX RX812, long cage, 42T max cogShimano Tiagra 4700, long cage, 34T max cogShimano 105 R7000, long cage, 34T max cog
CranksetShimano R460, 48/34, 175mm lengthShimano GRX RX600, 40T ring, 175mm lengthShimano Tiagra 4700, 50/34, 175mm lengthShimano 105 R7000, 50/34 (compact), 175mm length
BrakesShimano MT201 hydraulic disc, flat mount, 160mm rotorShimano MT201 hydraulic disc, flat mount, 160mm rotorShimano MT201 hydraulic disc, flat mount, 160mm rotorTektro HD-R310, hydraulic disc, 160mm rotor
CassetteShimano Tiagra HG500, 11-34, 10 speedShimano SLX M7000, 11-42, 11 speedShimano Tiagra HG500, 11-34, 10 speedShimano 105 R7000, 11-32, 11 speed
ChainShimano HG601Shimano HG601KMC X10Shimano HG601

Looking in more detail at the road groups, meanwhile, Shimano Tiagra has stepped up from its previous mark as a ‘slightly-better-than-entry-level’ group in the Shimano hierarchy. Both Tiagra and 105, much like Trek’s framesets, have profited from trickle-down technology and both offer superb value for money. That said, to get the most out of Shimano 105, its smooth shifting and range of gears, you want to be taking the Trek FX far beyond just the bike paths. Value for money is relative.

Wheelset

Buying Trek means Bontrager finishing kit, from the in-house component arm of the American giants. Bontrager wheels are standard fare across the Trek range and it is no different with the FX or the FX Sport. Three different wheelsets are used throughout the range. On the FX 1 and FX 2, it is Bontrager Connection hoops, on the FX 3, FX Sport 4 and FX Sport Carbon 4 you get Bontrager Tubeless Ready Disc wheels and on the FX Sport 5 and FX Sport 6 the Bontrager Affinity Discs.

It is standard fare, from the entry-level end of Bontrager’s vast range, and whether you feel the need to upgrade will center on your riding intentions. For the FX 1 and FX 2, the wheels are basic at best but you do get Bontrager’s H2 reflective hybrid tires with them. They include reflective sidewalls and are built to blend durability, smooth rolling, and grip.

RimsTires
FX 1Bontrager Connection, alloy, double-wall, 32-hole, schrader valveBontrager H2, wire bead, 30 tpi, 700x35c
FX 2Bontrager Connection, alloy, double-wall, 32-hole, schrader valveBontrager H2, wire bead, 30 tpi, 700x35c
FX 3Bontrager Tubeless Ready Disc, 32-hole, presta valveBontrager H2 Hard-Case Lite, wire bead, 30 tpi, 700x32c
FX Sport 4Bontrager Tubeless Ready Disc, 32-hole, presta valveBontrager R1 Hard-Case Lite, wire bead, 60 tpi, 700x32c
FX Sport Carbon 4Bontrager Tubeless Ready Disc, 32-hole, presta valveBontrager R1 Hard-Case Lite, wire bead, 60 tpi, 700x32c
FX Sport 5Bontrager Affinity Disc, Tubeless Ready, 28-hole, presta valveBontrager R1 Hard-Case Lite, wire bead, 60 tpi, 700x32c
FX Sport 6Bontrager Affinity Disc, Tubeless Ready, 28-hole, presta valveBontrager R2 Hard-Case Lite, aramid bead, 60 tpi, 700x32c

Again, the Tubeless Ready Disc wheels are the basic version of a range which stretches as high as the elite-level Aeolus hoops. The FX 3 uses H2 Hard-Case Lite rubber, while the FX Sport 4 and FX Sport Carbon 4 use R1 Hard-Case Lite. As indicated by the name, the H2 is built with hybrid bikes in mind, while the R1 is more aimed at road riding. Both feature Hard-Case puncture protection for durability, however.

Finally, the FX Sport 5 and FX Sport 6 step things up a little, with the Bontrager Affinity Disc-Ready wheels and R1 and R2 Hard-Case Lite tires respectively. As with all bikes, however, upgrading the rolling stock will make a big difference to your ride. The FX Sport 5 and FX Sport 6 are built for more dedicated road riding, so if you can afford to shop higher up the Bontrager range it will add an extra level to your riding. Out of the box, the supplied rolling stock will do the job though – but nothing special.

Ergonomics

Further Bontrager finishing kit extends to the saddles – Bontrager Sport, Bontrager H1, and Bontrager Montrose Comp split as above. The latter is built for versatility, with a cut-out saddle designed for comfort on or off-road, in an aggressive riding position. The Sport is a similar style but of a lower spec and the H1 is built with hybrid bikes in mind to offer a more cushioned ride – sans cut-out.
SeatHandlebar
FX 1Bontrager SportBontrager Riser, steel, 25.4mm, 30mm rise, 620mm width
FX 2Bontrager SportBontrager alloy, 31.8mm, 15mm rise, 660mm width
FX 3Bontrager H1Bontrager Satellite Plus IsoZone, alloy, 31.8mm, 15mm rise, 660mm width
FX Sport 4Bontrager H1Bontrager Satellite Plus IsoZone, alloy, 31.8mm, 15mm rise, 660mm width
FX Sport Carbon 4Bontrager H1Bontrager Satellite Plus IsoZone, alloy, 31.8mm, 15mm rise, 660mm width
FX Sport 5Bontrager Montrose Comp, steel rails, 138mm widthBontrager Satellite Plus IsoZone, alloy, 31.8mm, 15mm rise, 660mm width
FX Sport 6Bontrager Montrose Comp, steel rails, 138mm widthBontrager Satellite Plus IsoZone, alloy, 31.8mm, 15mm rise, 660mm width
Onto the bars, and the FX 1 uses Bontrager’s steel Riser bar – narrower than the others used at 25.4mm thick and 620mm wide. The FX 2 steps things up with an alloy Bontrager in 31.8mm and 660mm wide. Finally, the other five use Bontrager’s Satellite Plus IsoZone alloy bar, also 660mm wide. The wide bars ensure plenty of control when riding while the full package offers great versatility. In-built IsoZone elastomer inserts essentially supply extra suspension for your hands, while the ergonomic grip shapes further enhance comfort and reduce pressure. Again, for a flat-bar bike, it is a good spec that places the FX Sport right at the top of the range before you get onto fully-fledged, drop-bar road bikes. The Bontrager finishing kit is from the more basic end of their line, but then their top wheels and ergonomics are reserved for the top-end bikes. It is a trade-off between cost and top performance, but as a do-it-all fitness bike, there is little to complain about.