Trek Ion CX Pro
Trek’s Ion CX Pro is a race worthy bike that’s perfect for anyone serious about trying cross racing. Splitting the difference between the carbon race-whippet Cronus (reviewed last year by road.cc) and the more commuter focused Crossrip, the Ion CX Pro promises the best of both worlds at a wallet friendly (-ish) price point.
The press fit BB86 (86mm bottom bracket width) lops off some weight, as well as hiding those precious bearings away from all that mud and grit. The biggest advantage of running a wider BB shell is the increased real estate space it affords the downtube and the two chain stays. Up front, 1 1/8th to 1.5′ inch headset diameters, the standard now for cross bikes, are used to boost steering stiffness and braking response. A fork mounted hanger is another nice touch which, in conjunction with the massive headtube, eliminates brake shudder altogether. The fork is full carbon save for the aluminium dropouts, and provides bags of mud clearance around the front tyre.
The last piece in the monstrous front triangle puzzle is the top tube. The rear brake and derailleur cables run along the top of the top tube, whilst the front derailleur cable runs down the downtube. Moving onto the component spec, the Ion CX pro comes with Sram Rival for the shifty bits, Avid Shorty 6s for the stoppers, and Bontrager finishing kit and wheels.
Due to the complex cable routing in the shifter body, cable friction has always been a bit of an issue with Sram, with the company’s Red flagship group coming stock with gore sealed cables to address this. After a few muddy races and power washes, the shifting became impossible to set up right without resorting to a cable change. Rolling stock comes courtesy of Bontrager’s tubeless ready Race wheelset. In keeping with the current trend for wider rims, the Race rims measure 23mm across the brake track. This lack of compatibility may be an issue for those relying on a spare set of standard width wheels during a race.
But light weight and useful width is nothing if the wheel itself can’t stand up to the abuse a cross bike is subjected to. For any serious racing, something knobblier is advised. The Bontrager Evoke saddle looks well out of place on a race bike such as this, with its generous padding all round.
Swing a leg over it, and the Ion immediately feels like a traditional cross bike – tall and short. The included 90mm stem exacerbates this feeling and I swapped it immediately for a 120mm length to put more weight on the front wheel. With this revised weight distribution, I felt that the Ion was more willing to turn round tight corners where front tyre grip is all important.
State the frame and fork material and method of construction. List the components used to build up the bike.
Trek White/True Blue/Trek Black
200 Series Alpha Aluminium, E2, press fit BB, mudguard & rack mounts, cantilever brake bosses
Trek carbon cross, E2
50, 52, 54, 56, 58, 61cm
Bontrager Race, Tubeless Ready
Bontrager CX0, 700x34c
SRAM Rival, 10-speed
SRAM Rival, 34.9mm clamp
SRAM S300, 46/38
SRAM PG-1050 11-28, 10 speed
Bontrager Evoke 2, chromoly rails
Bontrager Race Lite, infinite tilt adjustment, 20mm offset
Bontrager Race Anatomic-C, 31.8mm
Bontrager Race Lite, 31.8mm, 7 degree
Integrated, cartridge bearings, sealed, aluminium, 1-1/8″ top, 1.5″ bottom
Avid Shorty 6 cantilever brakes w/SRAM Rival levers
Bontrager Gel Cork tape
Mudguard & rack mounts
Source = road.cc