Primer - Mid Grey - M/L+
The Primer is a bike built for 29 or 27.5+ wheels with geometry designed for aggressive all mountain riding. It is handbuilt in Canada by local fabricator Chris Dekerf in small batches that are painted individually for each customer.
The Primer uses what we would describe as our most progressive 29er geometry to date (excluding the Doctahawk!), notably the short chainstays, lower than ever BB height, steep seattube with a slack head angle, low stack headtube and long front center. This combination is the most versatile 29er we've ever built.
Building a frame with 27.5+ compatibility means that we had to redesign our ‘yokel’ junction to maximize the chainstay layout clearance. Incorporating a BB92 bb shell and boost dropout spacing also accommodates the most room possible for tire widths as wide as 3.0.
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 Travel // 160mm (±10mm)
Builder // Chris Dekerf and Mike Truelove
Click here to view the frame user guide.
* We hand ream PF92 BB shells carefully to a high tolerance and BB cup dimensions from different manufacturers vary. We follow SRAM-Dub specifications and SRAM BB cups are our first recommendation for the most accurate fit. If there is a specific BB/Crank combo you wish to fit to your frame, we can assist in evaluating the fit and even potentially ream and fit the BB for your new frame.
FRAME | Primer |
SIZE | Med Large |
PAINT | Gloss Mid-Grey |
FORK | Rock Shox Yari RC 170 |
STEM | Chromag HiFi 50mm |
HANDLEBAR | Chromag OSX 25mm Rise, 800mm Wide |
HEADSET | Cane Creek Forty ZS |
CRANKSET | SRAM NX |
BRAKES | SRAM G2 RSC |
ROTORS | 180mm |
SHIFTER | SRAM NX Eagle |
CASSETTE | SRAM NX Eagle 10-50t |
REAR DERAILLEUR | SRAM GX Eagle |
WHEELSET | Stans 27.5 Baron rims on Chromag R3 hubs. |
TIRES | Maxxis Minion DHF 2.8 / DHR 2.8 |
SEATPOST | Truvativ Descendant |
SADDLE | Chromag Lynx DT |
GRIPS | Chromag Clutch |
CHAIN | SRAM GX Eagle |
PEDALS | Contact |
Buy it with

Ridge Sock
Primer Geometry
Frame Size | STypical Rider Height: 155cm - 165cm | MTypical Rider Height: 163cm - 174cm | M/LTypical Rider Height: 172cm - 183cm | LTypical Rider Height: 181cm - 192cm | XLTypical Rider Height: 190cm - 200cm |
---|---|---|---|---|---|
630 | 630 | 639 | 648 | 657 | |
421 | 446 | 463 | 487 | 503 | |
578 | 603 | 622 | 648 | 667 | |
95 | 95 | 105 | 115 | 125 | |
1177 | 1202 | 1223 | 1251 | 1272 | |
50.8 | 50.8 | 50.8 | 50.8 | 50.8 | |
320 | 320 | 320 | 320 | 320 | |
677 | 714 | 738 | 762 | 799 | |
420 | 420 | 420 | 420 | 420 | |
368 | 406 | 431 | 456 | 494 | |
188 | 226 | 251 | 276 | 314 | |
64° | |||||
76° | |||||
29" |
* Max. post insertion based on Rockshox Reverb















