Best in Class: Comparing Our Favorite 27.5 Bikes

It isn’t easy to get a feel for a bike from geometry charts and images alone, much less an accurate comparison between similar models. For example, take the Ibis Mojo HDR 650B, Pivot Mach 6, and Santa Cruz Bronson Carbon. All three of these carbon, mid-wheeled trail-shredding machines have similar geometry, suspension, and intended usage, yet each is a distinctly different beast. Not coincidentally, these three frames are the basis for our upcoming 27.5-inch Featured Bikes Program this year. And since you may not have the luxury of logging hours on each bike, I’ve taken the liberty of doing precisely that. Hopefully, the experience will help point you towards the frame that best suits your needs.


With the Mojo HDR having the shortest travel of the bunch, it stands to reason that the handling is the most conservative. Its 130mm of DW-Link controlled travel is super-efficient under power, without giving up the small bump compliance that’s won DW-Link equipped bikes countless gravity races.


Photos: Re Wikstrom

Meanwhile, I found that the Bronson’s 150mm of VPP travel isn’t as snappy under power as the DW-Link bikes. However, if you run your suspension a bit stiffer than the recommended 25-30% sag, you’ll notice a marked improvement in its pedaling characteristics. As for the Mach 6, with 155mm of DW-Link travel, it flattens hairy terrain without giving up much under power. Admittedly, though, none of these bikes pedal like an XC race bike, but each of them pedals well enough for their intended uses.

Geometry & Handling

The Mojo HDR is the most reserved bike of the bunch. The higher bottom bracket and short reach contribute to this sensation, which tips the scale more towards quicker handling than stability. So, if you’re long of torso or arm, the Mojo isn’t going to be your cup of tea. The reach on the HDR is basically a full-size shorter than the Bronson or Mach 6 for any given size, with the long seat tube being a limiting factor if you ever want to size up. It has the same head angle as the Bronson, but because of the cockpit positioning, the steering feel is decidedly quicker.


I found that the Bronson is the roomiest out of the bunch, and with the longest chainstays, it’s plenty stable when you get it moving. Then there’s the longer front end. It gives you plenty of room to stretch out, making the Bronson surprisingly pleasant to climb on. In terms of fit, it’s a bit roomier, centering the rider between the wheels. Ultimately, this helps it to slice instinctively through corners.


With the slackest head angle, the Mach 6 is the most aggressive when it’s pointed down the trail. The short back end keeps it turning quickly, although the downside to the Mach 6’s high speed cornering stability is that it requires some added body English to change direction at slower speeds. And for the climbing-obsessed, the slack seat angle makes it less compelling than the others when grinding up steep singletrack.


The Mojo HDR is easily the stiffest bike out of the bunch. In fact, there are very few bikes that match it in terms of lateral stiffness. This makes it perfect for heavier riders, or for those that tend to land really hard. It’s not a free lunch, though, as the rigidity of the back end sacrifices a bit of grip at the limits of cornering traction — especially for lighter riders.


The Bronson is plenty stiff, but out of the three, it has the most give in the back end. However, this adds to its killer cornering manners. The finishing on the Bronson is arguably the best in this highly competitive group, though, with every detail being attended to by Santa Cruz. And in my book, the Bronson has the best tire clearance — a serious consideration for those who ride in muddy conditions, or for anyone that just likes big tires. Both the Bronson and the Mach 6 have exceedingly clean molded down tube and chainstay guards, which are easily overlooked, but a nice touch all the same.


The Mojo’s two main flaws are a tight tire clearance and a lack of stealth dropper routing. So, before you commit to a particular tire size, make sure that it’s not on the bigger end of the 2.3 spectrum. And lastly, the lack of a custom molded down tube or chainstay guard could also be seen as a drawback, albeit a primarily a cosmetic one.


The Pivot also has a relatively tight tire clearance, which is a price that you pay for the shorter chainstays. I also found that the cable routing above the Pivot’s rear shock requires very careful setup to avoid having it turning into a rat’s nest of cables. But what about the Bronson’s faults? Well, its VPP suspension design is more prone to packing up with mud than the DW bikes, So if you ride in wet conditions, a custom mud guard would be a good idea.

The Takeaway

The Mojo HDR is a burly trail bike with handling that, depending on your preference, is best described as either “old school” or “classic.” As for the Bronson, it’s a new school trail bike that’s confident at speed, and it asks the rider to push their personal limits. And lastly, the Mach 6 is really a purpose built enduro race bike, which is to say that it climbs acceptably well, while also being incredibly capable when pointed back down. Each is a sound choice for the right rider. So if you’re honest with yourself about how you actually ride, picking the right one shouldn’t be as daunting of a task as it appears on paper.

Love the builds in this article? Keep an eye out for them in our 2014 Featured Bikes Program in the next few weeks.

Shop the Selection

Santa Cruz Bronson Carbon

Ibis Mojo HDR 650B

Pivot Mach 6 Carbon

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