Height charts get you in the right neighbourhood. They don't tell you how a frame actually fits once you're on it. This chart uses the three numbers that matter for trail and enduro frames: reach, stack, and standover, the same numbers you'll find on a geometry chart from any serious frame builder.
Why Height Alone Isn't Enough
A height-based chart assumes every rider with the same height has the same proportions and wants the same fit. In practice, torso length, arm length, and riding style all shift what size actually works. Two riders at 5'9" can end up on different frame sizes depending on whether they want a stretched-out, stable position for aggressive descending or a more compact, playful setup.
Reach and stack solve this because they describe the actual cockpit shape, not just a size label.
The Three Numbers That Matter
Reach is the horizontal distance from the centre of the bottom bracket to the centre of the top of the head tube. It's the single best indicator of how stretched out you'll feel on the bike. Longer reach means a more stable, confidence-inspiring position at speed. Shorter reach means a more compact, agile feel.
Stack is the vertical distance from the bottom bracket to the top of the head tube. A higher stack means a more upright riding position; a lower stack means a more aggressive, stretched-out posture.
Standover is the clearance between your body and the top tube when you're standing over the bike. You want 1 to 2 inches (2.5 to 5cm) of clearance minimum, more if you're riding technical terrain where you need to get a foot down fast.
MTB Frame Size Chart: Trail Frames
| Size | Reach (mm) | Stack (mm) | Standover (mm) | Rider Height |
| S | 420–440 | 590–610 | 700–720 | 5'2"–5'6" |
| M | 445–465 | 605–625 | 715–735 | 5'6"–5'9" |
| L | 470–490 | 620–640 | 730–750 | 5'9"–6'1" |
| XL | 495–515 | 635–655 | 745–765 | 6'1"–6'4" |
MTB Frame Size Chart: Enduro Frames
Enduro frames typically run 10 to 20mm longer in reach than an equivalent trail size, favouring stability on steep, technical descents over climbing agility.
| Size | Reach (mm) | Stack (mm) | Standover (mm) | Rider Height |
| S | 435–455 | 605–625 | 705–725 | 5'2"–5'6" |
| M | 460–480 | 620–640 | 720–740 | 5'6"–5'9" |
| L | 485–505 | 635–655 | 735–755 | 5'9"–6'1" |
| XL | 510–530 | 650–670 | 750–770 | 6'1"–6'4" |
These ranges reflect what we see across current trail and enduro frames in stock. Every brand's geometry differs; always confirm against the specific frame's published geometry chart before buying, especially if you're between sizes.
Sizing Up or Down: When to Break From the Chart
Size up if: you ride predominantly steep, technical descents and prioritize high-speed stability over climbing agility. Longer travel enduro riders and taller riders near the top of a size range often benefit from sizing up.
Size down if: you want a more playful, easier-to-handle bike or you're on the shorter end of a size range and prioritize agility in tight, technical terrain over outright stability.
Stay on the manufacturer's recommendation if: you're building your first serious mountain bike or aren't sure yet what you prefer. Fit preferences develop with experience, and it's easier to adjust cockpit setup (stem length, bar width) on a correctly sized frame than to compensate for the wrong frame size.
Confirming Fit Beyond the Chart
Once you've picked a size from reach and stack, confirm in person:
- Stand over the frame with flat shoes on. You should clear the top tube by at least an inch.
- Check that your reach feels controlled, not overly stretched, in an attack position (standing, knees slightly bent, weight forward).
- If ordering a frame-only build, cross-reference the frame's exact published geometry chart against these ranges before committing to a size.
Shop MTB Frames at Dunbar Cycles & Corsa Cycles
We carry a full range of MTB frames and enduro-specific frames at both our Vancouver and Squamish locations. Not sure which size is right for a frame-up build? Bring your current bike's geometry numbers in, or your height and riding style, and we'll help you land on the right size before you order it.
