NAHBS 2013: Guru Unveils 670 Gram Photon HL Road Bike & More!

Guru’s new Photon HL was built from an engineering standpoint first, then they looked at design, with a goal of creating the lightest, stiffest bike on the market.

To accomplish this, the bike uses squared off tubes to maximize the “tangential surfaces,” which basically means there’s more of each tube surface that’s in tension, which is where carbon fiber gets its strength. Then, the layup uses patches and strips of carbon in a zippered layup called Quantum Carbon Concept. The result is a frame that’s just 670g for a size 54.

Check out detail frame pics, complete bike weights and the Photon R & SL and more after the break…

*Updated with prices for the SL and R models.

Construction is tube to tube. Cable ports, shown further down on the Photon R, are ready for mech or electronic with no parts swapping or retrofitting.

The bike uses a PFBB30 and straight headtube.

Compared to their previous bikes with a thinner dropout on the non-drive side, the new Photon models use symmetrically thick dropouts for equal strengths from side to side.

The complete bike weighed in at just 11 pounds. Of course, the frame is only part of the story for a bike this light, so here’s a bit of the build:

Extralite New Ultimate cockpit.

THM Clavicula carbon cranks and KCNC spiderweb chainrings and brakes. Wheels are Reynolds RZR tubulars.

Available late April. The Photon HL will be custom only, no stock sizes. Frame is $8,500. Rider weight limit is 220lbs.

The Photon R is the stiffest bike they’ve ever built, and they say it’s stiffer than any competitors’ bike they’ve measured, too. Unlike the HL and SL, it has a tapered headtube and thicker 31.6 seatpost (others use 27.2). It also switches to a PF86 BB.

Layup is optimized more for stiffness, but it still comes in under 800g (54), giving it a very, very good stiffness to weight ratio. It gets their FFR racing geometry. The Photon R is $5,000 for stock frame and fork, or $6,000 for full custom.

The SL uses essentially the same tube shapes as the HL, but uses different carbon and layup. Frame weight is 750g for a 54. It gets their FFX (Fast Forward Flex) geometry, which falls between race and endurance set up. Price is $4,500 stock frame and fork, and $5,500 for full custom.

All bikes come with ENVE 1.0 or 2.0 forks depending on model.

Not shown, the titanium Praemio R is now available in stock sizing with framesets at $3,600 with ENVE tapered fork (compared to $4,500 and up for custom). This bike was introduced last summer as a high performance crit race bike with oversized tubes to give it the stiffness needed for that discipline.

The titanium Meta XC hardtail now available in 650B/27.5. This one is a shop’s bike that built it up around 22 pounds. The model has been slightly updated in the stays to better accommodate the current range of drivetrains.

They also have a new singlespeed commuter bike with disc brakes.