At the recent Santa Cruz Mountain Bike Festival we had a chance to ride back-to-back the two hottest new carbon 29ers, the Ibis Ripley and Pivot’s Mach 429. We’re attaching our unique “On The Bike Review” videos here but also wanted to elaborate a bit now that we’ve had a chance to think the rides over.

At first glance, you’d assume these bikes are pretty much “carbon” copies of one another. They both spring from boutique backgrounds, they’re produced by two of mountain biking’s leading designers (Scot Nicol and Chris Cocalis), they both feature Dave Weagle’s DW-link suspension and they both aim at the top tier of quality, workmanship, esthetics and, of course, pricing.

What impressed us most about our rides, however, was how different these bikes are.

In a nutshell, the Ripley rides more like a really fast cross-country racer, while the 429 feels more like a ripping trail bike. Both can cross over into other disciplines, of course. But rider orientation is a big deal in choosing which of these bikes to go with.

What we noticed first about the Ripley was its flabbergasting climb prowess. Riding up forest trails, we easily were scaling step-ups, switchbacks and loose stuff that would have stopped us on a standard 26er, no matter how light and stiff. The bike tracked amazingly well, going right where we pointed it and offering effortless control, even when the front end was unweighted on the steeps.

At first we figured we were drunk on adrenaline, riding the cool new Ripley. And feeling really strong that day. Something we had for breakfast, perhaps.

Nope. The bike itself was the difference.

Hands-down, the Ripley is the best climbing bike we’ve ever ridden. There isn’t much more to say.

Part of this is the Ripley’s short chainstay (17.5 inches) and wheelbase (44.1 inches for a Large). Part of it is the DW-link configuration — built right into the frame rather than external. And part of it lies in Ripley’s fairly steep geometry — 70 degree head and 73 degree seat angles. The bike we rode was also pretty light, in the 26-pound range.

The Ripley’s climbing chops wrought an inevitable tradeoff, however.

On the downhill side, the bike felt less secure. It was a bit too upright to really settle down into. Although it cornered well and responded snappily on tight sections, there seemed to be a slight latency on drops, jumps and technical sections. We never were completely comfortable and never felt truly “centered” on the Ripley.

The caveat here, of course, is that we only had an hour on the bike and in no way could say it was completely dialed for our riding. But it’s also true that the climbing DNA of the Ripley may exert a tax on its downhill capability.

Note in the Ripley video that our take was shared by another rider testing out the Ripley whom we ran into heading back to the festival.

Our Ripley impressions also were confirmed by the ride on the Mach 429. While the 429 climbed better than our 26 and was certainly no slouch, it couldn’t touch the Ripley on the ups. A quick look at geometry gives a clue: The 429 has longer chainstays (17.65) and wheelbase (44.96), and slacker geometry (69.3 head, 71.9 seat). Also, as we note in the video, the Pivot’s front end sits noticeably higher, the head tube being 4.7 inches long v. 3.9 for the Ripley.

(All comparisons are for Large size, 120mm of travel and 2.1-inch tires, with similar Fox forks.)

Pointed down, though, the dynamic flipped. The 429 just railed. The cockpit felt immediately comfortable, the bike ate up berms, drops and jumps, and the suspension was supple and responsive. The bike felt more stable at speed and flickable on sketchy sections. Sitting on the 429, you really sink into the suspension, like the feeling you get when you manual a long-travel 26er.

The simplest way of putting it: The 429 was the first 29er we’ve ridden that really “disappeared” under us. We weren’t constantly reminded we were on a 29er. We were just out riding and having a blast.

You can’t go wrong with either of these bikes. But choosing which one may ultimately lie in your riding style and orientation as well as the trails you prefer. There was a time — when we were more racer boy and loved climbing better than anything — that the Ripley would have suited us better. But for all-around trail riding and just plain fun, we’d have to go with the 429. Beyond those two admittedly broad categorizations, the choice is up to you.

Mountain biking icon Joe Breeze, whose return to the sport he helped create we documented earlier in the summer, is about to unleash another round. At Dealer Camp in Deer Valley, Utah on July 29 (Thursday), Breeze will be showing two personal breakthroughs: His first carbon fiber frame, and his first set of 29ers.

Going by Cloud 9, a name we love, the new hardtails will hit the streets this fall, available in full builds (Limited Edition at $5,899 and Pro at $2,999) or as $1,799 framesets. It will have Breeze’s innovative twists, including rear brake calipers mounted on the chain stays for less howl and greater rigidity.

More to come! For now, here’s the eye candy …

Cloud 9 Pro (top) and Limited Edition