If bikes could be scored on looks alone, the expensive but stunningly built Occam TR M-Ltd would be well ahead of the pack. The clean full carbon frame mates well with the semi-concealed Fox Float DPS shock, while the kit hanging off the frame is a who’s who of high-end bike machinery.
As it turns out, we can’t just score on appearances alone, but that’s no bad thing for Orbea. In this case the looks aren’t cashing cheques the ride can’t handle.
Fast and furious
The Occam TR is built around Orbea’s UFO suspension technology. The carbon rear end has no pivot at the rear axle, but relies on the seatstays’ flex as it moves through its travel. Orbea says this not only keeps weight low (as there’s no metal pivot) but stiffness is also improved. On the trail there’s no stiffness issues and, with a complete weight of 11.9kg, it’s certainly no heavyweight.
No pivots back here, thanks to cleverly engineered carbon seatstays
The suspension is smooth, no doubt helped by the large DPS air can on the shock, which we’ve found to be a top performer in the past. Sat down and spinning uphill, there’s a ton of traction from the rear wheel on rough surfaces, despite the skinny Ardent Race tyre, although it can flounder in the mud.
Putting the power down along the flat is equally impressive, and the suspension allows you to remain seated for longer, saving energy. When you stand up, the pivot’s placement relative to the chainring means there’s enough anti-squat to keep the suspension’s bob in check for those mid-trail sprints.
This suppleness continues when the trail points down. While there’s no pivot at the back, the suspension remains compliant and active under braking, while the only skitteryness from the back end again comes from the Ardent Race, which looses traction a bit sooner than we’d like on a trail bike.
A 28t ring limits top speed, especially on long cross country rides
The shock, in its stock tune, is a touch travel-happy though – we feel it could do with a more progressive tune to help it ramp up a bit as it goes through its travel. In compressions and repeated impacts it’s prone to blowing through its travel, and we’d like a bit more mid-stroke support to keep the bike composed in such situations. To do this, you’d need to fit some volume spacers to the shock – thankfully a relatively easy job.
The front end is singing all the right numbers. 450mm reach (size large) might not be sled-like, but it’s definitely not short, and when matched with the 68-degree head angle and 35mm BB drop, the Occam is confidence-inspiring and stable at speed, while still retaining an element of agility in the corners. The carbon front triangle is stiff too, giving accurate and predictable steering, despite the Fox 32 forks (more on them later!).
So with plenty of speed on offer, we enjoyed riding the Occam but, and there’s almost always a ‘but’, we were left confused over the spec of the TR.
The frame is versatile – it’s light and efficient enough to race cross country or marathon on (although the Oiz is Orbea’s XC platform), but the suspension, with added progressivity and shape, would make for a great short?travel trail shredder. The spec seems to come from both camps though.
The Fox 32 fork and Ardent/Ardent Race tyre mix is more suited to an XC bike. The 32 is a Boost model, with the new 110mm axle width, which helps stiffness, but we feel the 34 would be a better match for the bike’s intended purpose, given its stiffer chassis for minimal weight gain.
The front end of the bike is prone to fore/aft flutter on rocky trails, and can be disconcertingly bendy in very hard braking zones. That said, lighter riders may find this less of an issue, and steering accuracy is improved over non-Boost 32s, thanks to the wider chassis and improved hub interface. The Ardents roll well, but lack bite in loose surfaces, hindering aggressive handling performance on man-made trails.
Fox’s 32 fork has improved stiffness due to its Boost spacing
On the flip side, if you’re after a more XC bike, the 28t ring is too low for longer XC rides where you might want to blast along the top of the moors. We suspect it’s chosen in part to help with the aforementioned anti-squat. However, there’s the option at purchase to spec a 30 or 32t ring, which may impact on this aspect of the frame’s performance.
Likewise, more cross country-focused riders may not need the XTR Trail brakes’ sheer power, or the Reverb Stealth dropper (although we certainly weren’t complaining!). Orbea has cleverly fitted an XT cassette – unlike XTR cassettes this gives you a 42t lowest gear, giving plenty of gear range.
As such, it seems odd to say, but we reckon this is actually the perfect bike for 24-hour racing. The handling is fun and predictable, and the suspension effective and efficient. The kit is reliable, light and, in terms of braking and dropping the saddle, ideal when you’re knackered and making mistakes – as is the 28t ring, which would be a godsend at 4am. Like looks though, a bike has to be scored on its overall performance, rather than on its suitability for a niche subsection of mountain biking.
The Occam is a supple performer on descents, though the shock could use a few volume spacers
Not as many bikes as we’d have expected have come with Boost spacing this year, but while a new standard is a pain for consumers and shops, there’s a benefit in wheel stiffness. The 29in Boost hoops on the Occam feel more like we’d expect a 650b wheel to. It could be argued that this new standard means that to get a 29in wheel as stiff as a 650b wheel now won’t cost extra in terms of needing a stiffer rim in the wheel.
Falling between two stools
Scoring the Occam is a tricky business. The frame is clearly a capable beast, one which we’d be happy to build up in either an XC or trail guise. Unfortunately we think Orbea has missed the mark with the TR M-LTD’s build.
It’s light and dripping in top-performing kit, but it’s neither an XC flyweight, nor a true trail thrasher. Transforming it into the trail bike we suspect it would love to be would be pricey, requiring a sturdier fork and chunkier tyres.
This article was originally published in What Mountain Bike magazine.