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Amy Dombroski's Primus Mootry custom

By:
Emily Wren/www.emilywren.com
Published:
December 02, 2009, 10:19 GMT,
Updated:
December 01, 2009, 23:44 GMT
Amy Dombroski (Schlamm p/b Clement and Primus Mootry) will finish out the 'cross season on a custom-built Primus Mootry.

Amy Dombroski (Schlamm p/b Clement and Primus Mootry) will finish out the 'cross season on a custom-built Primus Mootry.

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Up-and-coming cycling superstar Amy 'without a 'w' Dombroski (Schlamm p/b Clement and Primus Mootry) made an unusual move in late October by walking away from an existing agreement with then-sponsor Richard Sachs just six weeks into the terms of their contract, thus putting her on unfamiliar equipment – and unsure financial backing – right as the some of the biggest races were coming up.

Whichever side of the story you wish to believe (Sachs says Dombroski wouldn't honor her verbal and written contract commitments; she claims she couldn't be competitive on the sponsor-supplied equipment), Dombroski will now finish out the rest of the year on an aluminum and carbon fiber frame custom made for her by local builder Joe DePaemelaere of Primus Mootry and dressed for success with a host of gear sponsors she lined up after the break with Sachs.

Dombroski may pack a lot of power into her legs but she is also one of the smallest and lightest racers on the pro circuit at just 1.55m (5' 1") tall and weighing only 48.5kg (107lb). As such, she considers bike weight to be of prime importance and her new rig certainly fits the bill at a barely UCI-legal race-ready weight of just 6.88kg (15.2lb). Frame weight is just 1,340g (2.95lb).

"Lightness is a huge thing because you are picking it up and so much of 'cross is acceleration," said Dombroski.

Lying at the bike's core is a TIG-welded butted 7005 aluminum frame punctuated with a carbon fiber top tube and down tube from Edge Composites to both shave grams and soften the ride. The front triangle is devoid of fancy shaping with round cross-sections throughout; DePaemelaere instead relies on the carbon tube's directional lay-up to get the desired performance characteristics.

It's a different story out back as the S-bend stays are more dramatically massaged. The Dedacciai SC61.10A seat stays are flattened out below the brake bosses to ameliorate the pounding of rough courses and help maintain drive and cornering traction while the tapered chain stays are very tall and thin for drivetrain stiffness and mud clearance.

Up front, a standard non-tapered head tube surrounds a Ritchey WCS Carbon fork while DePaelemaere fits the special machine with an oversized BB30 bottom bracket shell. In total, Dombroski says her new machine is over two kilograms lighter than her previous setup and yet is still as rigid as she wants it to be.

"It's snappy and responsive when I accelerate and sprint on it and it's wicked smooth as well," she said. "There's also no fork chatter."

Also contributing to the bike's feathery weight is the premium build kit. SRAM provides its Force drivetrain and transmission (though technically second-tier it's virtually the same weight as Red), Reynolds supplies its MV32T UL carbon tubular wheels, FSA and fi'zi:k the seating and cockpit components, and TRP lends its ultralight EuroX Magnesium wide-profile cantilevers.

Interestingly, Dombroski's tire sponsor is Clement – a brand that just recently came back into the limelight but still doesn't actually have product to supply. As such, her bike was fitted with Challenge Grifo tubulars when we caught up with her a few weeks ago.

Two notable breaks from the standard Force group include a Red Powerdome cassette – which Dombroski says she only uses for dry conditions – and the crank set-up, which includes a single elliptical Rotor Q-Ring and secure-looking outer and inner guides from AceCo. Of course, the left-hand DoubleTap lever is also free of shifting internals to save weight.

Dombroski's unusual circumstances also necessitated an accelerated timeline. DePaemelaere reportedly built her two frames in the span of about a week and mechanical sponsor Excel Sports bolted them together in even less time than that, using fit numbers from the Boulder Center for Sports Medicine and the measurements off of her outgoing Richard Sachs bikes to make the switch as seamless as possible. Dombroski says she received the bikes on Friday, November 6 at 5pm and her first ride was her warm-up lap for a local race the next day – which she won.

Dombroski has in fact gone on to win more since then, taking the top step both days at the recent Super Cross Cup in Southampton, New York. Earlier in the year – and before the break with Sachs – she had hoped to make a trip to the UCI world championships in Tabor, Czech Republic, too, but that's now out of the question as her next sponsorship agreement with the Luna squad will kick in January 1 and she says they've asked her to back off of 'cross to prepare for the following mountain bike season.

Dombroski is understandably disappointed but at the same time realistic. Even at the ripe young age of 22, contending a full road, 'cross, and mountain bike season takes its toll.

"Worlds was my goal. But at the same time, presumably next year I'll hopefully be going even faster and will be able to do that much better in Europe and everything. They'll be plenty more times to go there."

The revised list of goals now focuses on the upcoming US national championships in Bend, Oregon, and the previous weekend's races in nearby Portland.

As for her chances at another stars-and-stripes jersey – Dombroski currently holds the US U23 title in both road and cross-country – she's hopeful but realistic. After all, also planning to attend is none other than current 'cross queen Katie Compton (Planet Bike).

"It's clear that Katie's on a different level," Dombroski admitted. "It was awesome to be able to race with her in Boulder and even for the short period that we were actually racing with her, it was cool to try and stay on her wheel. I lasted not very long – a lap or something like that – but it was very similar to Providence when I was trying to stay on Katerina's [Nash] wheel. They have the power and finesse down to an art. Out of every corner they're just so powerful but they go into it and don't even touch their brakes. It's just so effortless and efficient and that's something I've been working on. She's the best rider in the world right now. She's phenomenal."

Full Specifications

Complete bike specifications:

Frame: Primus Mootry custom, butted 7005 aluminum w/ Dedacciai SC61.10A MTB seat stays and Edge Composites carbon fiber top tube and down tube
Fork: Ritchey WCS Carbon Straight
Headset: FSA Orbit X CX
Stem: FSA OS-99, 9cm x -6º
Handlebars: FSA K-Force Compact, 40cm (c-c)
Tape/grips: fi'zi:k bar:tape
Front brake: TRP EuroX Magnesium w/ TRP carbon-specific pads
Rear brake: TRP EuroX Magnesium w/ TRP carbon-specific pads
Brake levers: SRAM Force DoubleTap
Front derailleur: SRAM Force
Rear derailleur: SRAM Force
Shift levers: SRAM Force DoubleTap w/ empty left-hand lever
Cassette: SRAM OG-1090, 11-25T (dry conditions only)
Chain: SRAM PC-1090R
Crankset: SRAM Force BB30, 170mm, w/ 42T Rotor Q-Ring
Bottom bracket: SRAM Force BB30
Pedals: Crankbrothers Candy 4ti
Wheelset: Reynolds MV32T UL
Front tire: Challenge Grifo 32
Rear tire: Challenge Grifo 32
Saddle: fi'zi:k Antares k:ium
Seat post: FSA K-Force SB0
Bottle cages: n/a
Computer: n/a
Other accessories: AceCo K-Edge outer chainring guard and inner chain watcher, Gore Professional derailleur cable set

Critical measurements:

Rider's height: 1.55m (5' 1")
Rider's weight: 48.5kg (107lb)
Saddle height, from BB (c-t): 633mm
Seat tube length, c-t: 495mm
Seat tube length, c-c: 450mm
Tip of saddle nose to C of bars (next to stem): 435mm
Saddle-to-bar drop (vertical): +10mm
Head tube length: 100mm
Top tube length: 500mm
Total bicycle weight: 6.88kg (15.17lb)

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