Chromag has updated the Rootdown frame with a combination of longer top tube, shorter chain stay, slacker head angle, steeper seat tube and lower BB. For Chromag it was a significant progression of all mountain hardtail. The new 2019 version continues that legacy further with the additional clearance needed for 27.5 Plus tire compatibility.
Built with their custom-drawn tubes and featuring a 12 X 148 Boost rear end and stealth post routing, this is the evolution of Chromag frame design in 29er form compatible to 27.5+. An agile ascender and a dominant descender that is ready for anything.
- Midnight Blue
- Harvest Gold
- Hunter Green
S, M, M/L, L, XL
Almost all Chromag frames are made from quality 4130 chromoly steel tubing. Chromoly is an abbreviation for chromium-molybdenum indicating the materials that the steel is alloyed with.
The added chromium helps increase the steels hardenability and also provide some corrosion resistance. The molybdenum helps to increase the toughness of the steel.
It has a high tensile strength but is also malleable which is what gives our frames their notorious ride quality and feel. Chromoly is often used when more strength is required than that of mild carbon steel.
It falls under the AISI (American Iron & Steel Institute) 41XX designations which is where the “41” comes from. The “30” indicates it contains approximately 0.30% carbon by weight.
Chromoly is much stronger than traditional 1020 steel and it has a higher strength to weight ratio and high tensile strength, which means we can use less material and achieve a product that can withstand the abuse that riders love to throw at it.
Hub Spacing: Boost 148mm (Axle and Hanger Included)
Headset: 44-56 Semi Integrated
Seat Clamp Size: 35mm
Seat post Size: 31.6mm
BB: 92mm Press Fit (PF92)
Wheel Size: 29″ or 27+
Recommended Fork Length: 150 – 170mm
ROOTDOWN FRAME GEOMETRY
|Effective Top Tube||22.5||23.2||24.1||25.0||25.8|
Head Tube Badge
Your bike is special. The head tube badge is the finishing touch so they’ve always made a point of taking the time to do something interesting with it. Their head tube badges have changed over the years and are an indication of the time each bike was made. Whether it’s a cast bronze, or polished stainless steel, water cut aluminum or a 3D CNC carving, each one represents our commitment to detail.
As 12mm through axles have proven to be solid, reliable and convenient, they have committed most of their models to utilize this format. Their 12mm dropouts are accurate and tough and feature a removable derailleur hanger with a sturdy interface for strength and reliability. All 2017 models (excluding Monk and Nice Dreams) will follow the 148mm boost spacing.
Chromag’s ‘Yokel’ design is a small machined junction on the chainstay that helps accommodate both tire clearance and chainring clearance. Their first versions were huge CNC yokes that bridged the entire front end of the chainstays. Over time they refined this to minimize weight by arranging our chainstay layout asymmetrically and reducing the yoke to a minimal size. It’s one of their most unique frame features and has been copied by other frame makers.