2015 Orbea Oiz M20 mountain bike long term review and actual weights

First revamped in 2012 as a 26” World Cup race rocket, the Orbea Oiz switched to 27.5” and 29er wheels for the 2015 model year but kept it’s XC race pedigree. At the launch event, we rode it through the mountains of France, putting it through plenty of uphill and flowing pedaling sections and some steep, aggressive descents. First impressions were very good, so we brought one in for long term review.

The upper/mid-range Oiz M20 29er arrived, offering a mix of SLX, XT and XTR components, DT Swiss wheels and Race Face cockpit parts for $4,999. The Oiz is offered in both 27.5″ (S/M/L) and 29er (M/L/XL) wheel sizes, and carbon fiber levels. The M20 uses their OMP level carbon frame, which is about 200g heavier than the top level OMR carbon found on the M10 and higher models…which start at $6,299 and go way up from there.

On paper, the bike would be perfect for our very XC-ish local trails in Greensboro, NC. The rear suspension is efficient, travel is short and the frame was now proven under Catharine Pendrel. And for a while it lived up to the hype…

DETAILS & ACTUAL WEIGHTS

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The spec at this level leaves little to be desired, using respected name brand parts everywhere. Like virtually every bike, it ships with tubes, but I immediately set up the Maxxis Ikon 29×2.20 tires tubeless.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The frame is heavily shaped everywhere, which is typical for Orbea. It’s done mainly for stiffness here, but as you’ll see, it also adds functionality. All internally run cables enter at the front of the head tube (shift cables and rear shock remote). The rear brake hose runs outside the downtube.

Stack and reach on the Oiz follow linear, proportional growth across frame sizes, and head tubes are short on all of them so the rider can get in a low racy position if desired.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

If you appreciate having a lockout, you’ll like knowing the front and rear CTD suspension is controlled by a single lever, but it creates a very cluttered cockpit. Honestly, the rear suspension is so efficient here (thanks to the high leverage and compression ratios used, which are detailed in our post from the bike’s launch), that I kept it in Trail mode almost exclusively, even when descending because the “D” mode on Fox’s 2015 32-series forks was simply too soft and blew through the travel. Unless you’re racing for the rainbow stripes, it’s my opinion this bike would be better served (and lighter) by ditching the lockouts and going with the RS-1 up front. Or the new 2016 Fox 32. Considering the intended use, this bike screams for a better XC fork.

It’s worth mentioning that when we rode the Oiz at launch, several of us jimmied the cable’s position to set the fork in Trail while the shock went to Descend, which worked great.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The rear suspension linkage is minimal and sleek. Smaller frame sizes lack the split top tube, but it helps reinforce the seat tube on the XL we tested.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The frame is ready for any drivetrain and shock system, mechanical or electronic (Di2, iCTD). In fact, our first ride on the new XTR Di2 was on one of these.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The most unique feature of the Oiz is the small steel strut (looks like a spoke) used to tie the seatstay pivots together. It’s not there to keep each side from acting independently, rather to keep the linkage from spreading apart under compression and wearing prematurely. That’s the stated intent anyway, in reality it seemed to have a massive impact on rear end stability. Keep reading…

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The bottom bracket shell is extra wide, sized for PF92. It, along with the angular downtube shaping made for a solid pedaling platform with negligible if any pedal bob while seated and minimal bob while standing. Putting the suspension in “Climb” mode made it feel like a hardtail.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

On the other side of the BB, the rear derailleur cable housing exits the downtube and runs through a liner between the BB shell and swingarm and through a guide to redirect it along the bottom of the chainstay. Another cable port just above the one visible here is for Side Swing front derailleurs, but this bike used a traditional FD.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The seatstays are slim, designed to bow upward to make up for the lack of a rear pivot near the axle. Orbea stuck with a 135mm QR to save weight and make for quicker wheel changes. More opinion on this coming up soon, too…

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The inside face of the dropouts is metal to prevent wear and tear between hub shell and carbon.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

Plenty of clearance top and bottom for the Maxxis Ikon 29×2.2 tires.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

The complete bike, size XL and without pedals, came in at 25.49lb (11.56kg). Spec includes alloy Race Face bar, stem and seatpost, DT Swiss X 1700 wheels, Maxxis Ikon TLR 120tpi tires, Selle Italia SL XC Flow saddle, SLX shifters/brakes/front der., XTR rear der., and Fox Factory suspension. Retail is $4,999.

RIDE REVIEW

2015 Orbea Oiz M20 mountain bike long term review and actual weights

Lemme start this off with a list of pros and cons, as it’s mostly positive bullet points:

PROS:

  • The Oiz very fast and efficient both sitting and standing, with great power transfer even while leaving the suspension fully active. Catharine Pendrel is pedaling this to World Cup XC wins, albeit with a bit different spec, and there’s no doubt why.
  • It rockets uphill and along the flats, whether they’re smooth or rooted.
  • Along those lines, you can keep hammering through roots, rocks and other trail chatter with no fear of pedal strike. This particular feature stood out as I could pedal through rough sections that I’ve clipped pedals on with other bikes. The BB height is 325mm (12.79″), with a BB drop of 45mm. That’s more drop than both the Specialized Epic (40mm) and Niner JET9 (35mm), two 100mm travel bikes, the latter of which I ride as my daily bike, yet the Oiz felt like I could pedal through stuff more cleanly. This could be due to the lower sag recommendations on the Oiz combined with the firmer rear suspension. Whatever it was, it worked…
  • …and without giving up a capable suspension. The Oiz handles aggressive terrain far better than its XC branding would suggest. I wouldn’t throw a bigger fork on it, but it handled some Pisgah Forest exposure just fine.
  • Decent front triangle stiffness meant the bike felt solid when rocking it back and forth in sprints or driving into a corner.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

CONS:

  • It could do without the lockouts, doesn’t really need it in the rear unless you want to feel like you’re racing a hardtail.
  • This bike was made for a fork like the RS-1 and would be made much better by spec’ing the newer Fox forks or similar. It’s not the bike’s fault, but the entire 2015 range was spec’d with CTD forks.
  • While the front end was plenty stiff, the rear end could be stiffer. This is my only real performance complaint, so I’ll elaborate:

If there’s one thing we can give Orbea credit for, it’s going for it. They had an idea to do it differently and they went for it. And for some riders, it probably works just fine. The Oiz suspension’s design was done to save weight wherever possible. There’s no pivot at the rear axle, instead relying on the seatstays to flex. And they stuck with the quick release to save grams compared to a thru axle.

Another key design choice they made was to make the upper linkage out of carbon rather than aluminum. That saved ~45g, but it required a spoke-like strut to keep the pivot arms from splaying outward. It was this explanation of the strut’s purpose that made my experience with the bike all the more flummoxing.

2015 Orbea Oiz M20 mountain bike long term review and actual weights

After a month of riding, the rear end started getting sloppy, like a sailor that hadn’t found his sea legs. The rear end would lag behind in corners, and the overall stability of the bike just fell apart. I could grab the top of the rear tire and wobble it back and forth almost 2cm. Problem was, everything seemed to be tight. The upper and lower suspension pivots were tight. The skewer was tight. The hub and bearings were tight. Yet there was a tremendous amount of play at the rear wheel, making the bike unrideable.

Turns out, the strut worked itself loose, but not so loose as to be apparent. But once it was loose, the quality of the ride went to pot.

Fixing it literally amounted to a turning the strut’s outside bolt (I also gave the inner bolts a few small turns to be safe) and the rear end was back to normal, and it stayed that way for the duration of our test. Considering it’s not marketed as a structural stiffening component on the bike, the strut’s impact on performance was very surprising.

Once fixed, the rear end is stiff enough. It’s not the stiffest, but it worked for my admittedly-large-for-an-XC-racer frame of 6’2″ and 190lbs (188cm / 86kg). For comparison, Pendrel and her teammates look to be maybe 100lbs soaking wet and they’re killin’ it on this bike. My feeling is that a rear thru axle and using a larger diameter hollow axle in place of the strut, even if only 10mm round, would provide massive gains in stiffness with minimal weight penalty. And that would make an otherwise very good bike an excellent race bike for XC and marathon for any size rider.

Orbea.com

23 COMMENTS

  1. Who rides bikes without pedals? Can anyone actually do it?

    Why not just weigh the bike without tires, grips, saddle, etc – someone may choose to put their own preferences of these items instead…

    Too bad the full weight would make the bike seem heavy and overpriced per weight..!

  2. bikeduder – we weigh them without pedals because it’s consistent for any bike we weigh, apples to apples, and because that’s how you’ll pick up the bike at the shop unless you want cheap plastic flats used for demo rides in the parking lot. There are so many different brands and types of pedals that it’s not practical to include them in complete bike weights since the pedals you use are likely different. Best bet is to weigh your pedals, then add that to any published weight you see for a bike.

  3. archie – FWIW, it depends on the design if it really matters. On a true URT bike like the Niner JET9, the gains in stiffness were infinitesimal and the thru axle added weight (their words, not mine), but consumers demanded it so they did it. I have two JET9 RDO’s in my stable, one with QR and one with TA and they ride identical to one another. On this bike, though, which uses independent sides that are only joined at the chainstay yoke, I do believe a thru axle would make a noticeable difference for heavier riders.

  4. Tyler – To test your thru-axle theory try installing a bolt-on skewer like the Halo Hex Key and see if it makes any difference to rear-end stiffness.

  5. I don’t have problems at all with rotor position after putting the wheels back on the bike, with QR…XT brakes, maybe that matters.
    In fact, I’ve been using for some days a hardtail 29er with thru axles in both ends, and those’ve been a pain in the ass every time I had to put the wheels back after a car ride or whatever.Specially the front, with an evil Manitou QR, that takes quite a while to get used to.
    Every time I swap wheels in my QR equipped MTB, or road bike, feels like heaven.
    Ah, TBH, I didn’t find any advantage with the thru axle, even in stiffness.

  6. Pasabaporaquí – Probably the main reason those thru-axle wheels are a pita to put back on have to to with tight fitting disk pads and aligning them in. Axle system doesn’t change how a wheel goes in.

    Having grown up used to QR for many years, I could take of and mount QR wheels blindfolded, so changing to thru-axle might get a while getting used to, but that doesn’t mean it’s better or worse.

    Thru axles have other benefits, other than stiffness:
    – The interface with the fork/frame is designed by the same fork/frame designers, so it can be as good or bad as they want to! Hub designers just have to focus on their side of the problem.
    – Wheel alignment is always perfect, even if not tightened properly. Noobs are saved! Best of all your wheel isn’t going to fall off.
    – Larger diameter axles allow designers to play with newer materials and overall have better weight and strength. 9mm QR was designed when the best material available was wood.

  7. in XC theres a lot of steep uphill so weight actually matters quite a bit more than road cycling (or dh/enduro/blah .. specially dh where weight basically doesnt matter)
    500gr+ start to make a diff you really feel.

  8. XTC – it’s an Orbea helmet (Model: MTB1-Y-1), and it’s very comfortable and reasonably light. Much more normal looking and better fitting than some of their other models from years past.

  9. Thanks for the review. Do you think a smaller size, 27.5 version would still have the same cons? Also how did the bike perform on decents?

  10. I have this bike, and I can attest to everything written. Being 6’2 240 and riding everything from XC races to 24 hour Endurance Races. The bike has been nearly flawless. I too had the same issue with the strut loosening after about 200 miles, and I also wish the bike would have come with a 12mm thru axle like the 2016 Ocaam will… But all in all, this bike has been pretty awesome. 25.5 lbs for an XL 29er, full suspension with pedals…

  11. I have an OIZ M30, I have put over 1000 miles of single track trails in just about 11 months and I can say that it is the best mountain bike I have ever owned. (I had a 2013 Epic Carbon, and a niner RIP RDO 2013 ) This bike is a racing bike it isn’t the most comfortable for extra long rides but it is the most nimble and accurate bike of the three. As I have it set up today it is just under 25lbs (L) frame, XTR everything other than brakes, those are still SLX, the result are dynamics perfect for cross country riding. The tires have been excellent, the fork, shock and accesories have worked better than I expected. The only changes I have done have been out of pure stubbornness or as a result of a crash, with only regular maintenance I already can tell that this bike has the potential to outlast my old aluminum bikes.

    I honestly believe that this bike can be one of the best of bikes ever produced, it has a great design, excellent workmanship and so far great customer support.

  12. So I’ve read this review and despite the spoke problem, I got it anyway. Sounds more like an ajustment than a real problem. Anyone cam tell me how the spoke adjustment must be done? The manual says 0,5nm on it. Seems so few. When you guys retight the spoke, how much torque do you leave there?

  13. I have 1700 miles on my 2015 M20 OIZ, I have had specialized mountain bikes and without a doubt this bike is the best XC Carbon bike of them all. I have always been a fan of FOX and they don’t disappoint with the fork and shock. The stock tires are great (MAXXIS Ikon) the Shimano components are reliable and work perfectly as long as they are maintained. My large frame with XTR pedals is under 24 pounds I have upgraded most components to carbon and run single 36T chain ring up front. Overall the geometry and suspension design make this bike an excellent climber and great on the descends. I had an issue with the tension bolt but the dealer took care of it right away.

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