Frames

Why buy a frame only?

Building from a frame means every component is your choice. You can run the exact fork, wheels, brakes, and drivetrain you want rather than compromising on a complete bike's spec. It also makes sense when you already have components from a previous build, or when the frame you want isn't available as a complete. Buying a used frame and speccing it with a mix of new and used parts often gets you a better bike for less money.

What to check on a used frame

Inspect the head tube, bottom bracket shell, and shock mounts for cracks — these are the highest-stress areas. On full-suspension frames, check every pivot bearing for play by grabbing the rear wheel and rocking it side to side. Look at the derailleur hanger (ideally get a spare — they're cheap insurance). Carbon frames need careful inspection for impact damage on the downtube and chainstay. Ask about crash history. A frame with fresh bearings and a straight hanger is ready to build; one with worn pivots will need investment before it rides well.

Frame sizing

Frame size is the single most important spec on a mountain bike. Too small and you'll feel cramped and twitchy; too big and you'll struggle to move the bike around. Reach and stack are more useful measurements than traditional seat tube length. Most manufacturers publish geometry charts — compare reach numbers rather than relying on S/M/L labels, which vary between brands. If you're between sizes, go smaller for a more playful bike or larger for stability at speed.

Carbon vs aluminium frames

Carbon is lighter and can be shaped for better stiffness-to-weight, but used carbon needs careful inspection for hidden damage. Aluminium is tougher, cheaper, and easier to inspect visually. For aggressive riding (enduro, DH), many riders prefer alloy for its durability. For XC and lighter trail riding, carbon's weight advantage is more noticeable. Both materials make excellent frames.

Frame disciplines

Browse by type: trail frames (120–150mm), enduro frames (150–180mm), XC frames (80–120mm), downhill frames (200mm+), hardtail frames, and dirt jump frames. Need complete bikes instead? Browse mountain bikes.