Enduro Carbon 27.5 Rig: It's just a prototype, for now…

When a company spends upwards of $100,000 per carbon mold and makes three of said molds, it's a safe bet that something new is moving quickly down the pipeline toward public availability. That would certainly appear to be the case with Giant and the burgeoning realm of 27.5-inch mountain bikes.

The proof? During the bike maker's recent mountain bike team unveiling at its U.S. headquarters in Newbury Park, California, there were four stealthy black prototype tweener-wheel-sized bikes on clear display, including three with carbon fiber front triangles, meaning a ton of R&D money has already been invested.

And while company PR man Andrew Juskaitis wouldn't divulge specifics about the yet-to-be-named steeds, it appears that Giant is all in on 27.5. That's big news considering it's the world's largest bike maker, and makes you wonder how long before the likes of Specialized and Trek get in the mid-sized-wheel game. (It's also worth noting that Giant says it will not use the "650b" nomenclature because it's too confusing for the consumer).

"Across the board, we have a very strong belief in the future of 27.5 bikes," said Juskaitis, who himself has been riding and providing feedback on the new bikes. "We've been testing for two years now and have found that 27.5 takes the best characteristics of a 29er - traction and stability - and brings the zip of a 26-inch wheel. It's a total cliché, but it really is the best of both worlds in our eyes."

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Juskaitis also bluntly acknowledged that he didn't expect all three wheel sizes to exist very far into the future. "It's a tremendous pain to make all three, and have our shops understand three different technologies, and have our shops carry all those wheels and tubes," he said. "We just cant sustain three wheels sizes. It's too many skus. You have to kill something."

Presumably that means the eventual death of 26-inch mountain bikes, but Giant wasn't willing to make that leap just yet. Instead, Juskaitis pointed out that the still-in-development bikes have been designed from the ground up to fully compliment the qualities of 27.5.

"We maintained the Maestro suspension design, but everything else is tweaked to accommodate for the new wheel size," continued Juskaitis. "We feel like a lot of our competitors are just throwing 27.5 on whatever established frame they have. That's not our approach. We have been working on this for a long time. We started from white papers and didn't rush."


Giant MTB Team: PR man Andrew Juskaitis intros the 2013 team.

Because the bikes are still in prototype phase, Juskaitis claims Giant could still back out. But the fact that the likes of Adam Craig, Carl Decker, Josh Carlson and Kelli Emmett will all be racing the mid-sized-wheel bikes in the field this year speaks for itself. And then there are those molds.

"A carbon mold per size costs between $75,000 and $100,000 per and you cant change them," said Juskaitis. "Once they are cut, they are cut. So make your own guesses as to where we are."

Sounds like we'll be seeing production Giant 27.5 models sooner rather than later, which is something Craig certainly approves of. Just ask him which wheel size is best for enduro racing?

"I honestly think the 27.5 might be it," said the former cross-country Olympian who will be racing enduro full time this coming summer. "We spent some time on samples last fall at home on familiar stuff and it really clicked. For enduro you need to be able to run thick tires, maybe not downhill thick, but something pretty close. But once you start putting a tire that heavy on a 29er, which you would need to do when you got into tighter, steeper terrain that is rockier and burlier and requires a heavier casing tire, you end up with a really heavy tire, say 1300 grams for a 29er. And we know that makes any bike ride poorly."

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Craig sees the 27.5 as a perfect compromise. Even thicker casing tires will only run in the 900-gram range, and the new bikes handle really well, he says. "It's easier to get the back end where you need it, easier to keep the bottom bracket low and not have a ton of bottom bracket drop. So far I am really happy with it, and that is coming from someone who mostly likes the way 29ers handles."

As for those four prototype bikes, here is what we learned during our one-day visit with Juskaitis, Craig, and the rest of the Giant mountain bike crew:

Adam Craig's Alloy 27.5 Enduro Bike: The former Olympian will attack the world enduro circuit on this stealthy steed.

-- Four 27.5-inch bikes were on display, one full alloy and three with carbon front triangles and alloy rear ends. Drivetrains were SRAM XX1. Wheels were DT Swiss LTD Edition.

-- The full alloy rig, which had Craig's name on the top tube, and one of the composite frames looked similar to Giant's Trance model trail bike. Geometry was relaxed, and spec included 140mm RockShox Revelation fork with a 15mm thru-axle, ISCG chainguide tabs, RockShox Reverb dropper posts, 142mm rear thru-axles, RockShox Monarch Plus RC3 shocks, and Schwalbe Hans Dampf Super Gravity tires. Other features included internal cable routing and tapered headtubes.

Alloy Rear-End

-- These are the bikes Craig, Carlson and Decker will ride during the upcoming enduro season, which for Craig and Carlson means spending extended time in Europe, chasing glory on the newly launched Enduro World Series circuit.

-- The other two bikes bore great resemblance to the existing cross-country-oriented Anthem X model line, utilizing more aggressive geometry and spec'd with a 120mm RockShox SID RCT3 forks and 100-120mm RockShox Monarch RT3 shocks. Like the longer travel rigs, these bikes included internal cable routing and tapered headtubes.

Kelli Emmett's new toy

-- During an afternoon ride on nearby trails (which were fantastic, by the way), Giant Factory Team rider Kelli Emmett was piloting the smaller sized XC-looking bike, opening up the possibility that Giant might be adding to its women's specific Liv / Giant line with a 27.5-inch Anthem.

-- This could indicate Giant's answer to the issue of creating small framed 29ers, which poses engineering challenges and can be unwieldy on the trail. The 27.5 wheel size provides more design options, and might just end up being the better option for women who want an alternative to 26-inch bikes, but don't want to jump all the way to a 29er.

That's all we know for now, but we'll keep eyes and ears open, providing more details as they become available. Until then, here's an extended photo gallery of the prototype bikes and the team that will be piloting them.

Photos courtesy: Jake Orness / Giant Bicycles