Orbea

Occam Carbon

The Orbea Occam Carbon can be thought of as a cross between their World Cup-proven cross country race machine, the Alma, and their all-mountain capable enduro bike, the Rallon. It looks the part, and in fact it borrows technology, style, and design concepts from both. The carbon fiber Occam even fills a performance gap between the two. However, as its own bike, it’s made to compete with the best of the new breed of super trail bikes on the market. To underscore that point, the Occam weighs in at less than five pounds, yet it has a comfortable and capable 4.84” (123mm) of rear wheel travel.

Orbea molds the Occam front triangle and swingarm as one piece with their Silver grade carbon fiber. This results in structures with uninterrupted fibers and no joints, and this is part of why Orbea can build the Occam so light, even though it’s intended for racing and hard trail riding. The Silver carbon offers a just-right blend of light weight, impact resistance, and toughness.

The Occam came to fruition thanks to Orbea’s Advanced Dynamics modeling and research. One key element was that they designed the bike with the rider in mind, and their modeling and testing always included a virtual rider to exert forces on the frame the way you would as you ride the bike over all types of terrain. The design process was completed with mountains of feedback from riders aboard functional prototypes. The final result is a bike that’s perfect for marathon racing.

By saying that, we’d like to point out that marathon racing embodies all that we see as good in the Occam. It responds to furious pedaling efforts with sheer acceleration. Twists of the bars send steering input to the front wheel without hesitation. It climbs with near-hardtail-like efficiency without the strength-sapping effect of absorbing bumps with your legs and back. The bike does this for you, even as you pedal. Is the Occam faster than the Alma over the duration of a six hour race? Perhaps marginally because of the greater level of control and traction afforded by the full suspension design. Will you be faster over the same distance aboard the Occam? Considerably so.

While the Occam looks similar to the Rallon at a glance, the differences between the two are real. Aside from the material and travel differences, the Occam rear suspension employs a different layout. Like the Rallon, the Occam uses a single pivot for the swingarm, located on the seat tube a bit above the bottom bracket shell. In a different twist, the pivot with the seatstay is concentric with the rear axle. This pivot location allows the left seatstay to function like the brake floaters that downhillers have used for years. The advantage here is that your rear suspension is free to cycle through its travel range while you're hard on the brakes. This is most evident on rough-braking whoops or tree roots just before a turn. Your rear suspension can still follow the ground effectively while you exert a powerful braking force. And the more traction you have (since the tire can follow the ground) the harder you can brake and the harder and deeper you can push into corners. This is how you go fast.

Smart design details abound on the Occam. For starters, the cable routing is as clean and simple as it gets. As bike mechanics, we often see botched jobs here, like it’s an afterthought. Orbea routes the rear brake and rear derailleur housing along the top edge of the down tube. Special machined clamps hold it all in place, and the lowest is positioned to also accept the fastener through your water bottle cage. The front derailleur cable is routed internally through the down tube, emerging through a special silicone gasket just above the bottom bracket shell. The gasket keeps mud and gunk from entering the frame. And perhaps our favorite smart detail is the seatstay assembly. It’s made of aluminum. You might be asking why aluminum? Why our favorite part? It’s because the seatstays on any bike function under compressive forces. And since carbon is weakest in compression, this is a wonderful place for a nice, lightweight alloy part.

The Occam is built with adaptability in mind. You can use it with either 120 or 140mm front forks to complement the custom-valved Fox RP23 rear air shock. With a 120mm fork, you’ll have a 68.5˚ head angle for a more agile feel and quicker steering. Installing a 140mm fork will stretch the wheelbase out a touch and reduce the head angle to 67.5˚ for a slightly more stable and forgiving ride at speed or on steep descents. Like the Rallon, the Occam relies on sealed cartridge bearings at every suspension pivot. The one at the concentric pivot is no exception, and the dropout design allows the use of different axle types, including thru-axles. We have it configured here for standard quick release hubs, but conversion kits are available for 142x12mm thru-axles.

The Orbea Occam Carbon is available in Carbon/blue and Carbon/red, and it comes in four sizes – X-Small, Small, Medium, and Large. It has an English threaded bottom bracket shell and takes a 31.6mm seatpost and 34.9mm high clamp/bottom pull front derailleur. It has a tapered head tube and comes with an FSA 1-1/8” to 1.5” integrated headset. You’ll also get a post mount rear brake, eliminating the need for adapters if you’re using 160mm rotors. All Orbea frames have a lifetime warranty against manufacturing defect.