Every figure on this site is either a manufacturer spec or a calibrated estimate. Here is exactly where each number comes from, how the drawing is built, and where the limits are.
Seat height and wheelbase come straight from the manufacturer’s published specifications, verified across the maker’s own site, media reviews and spec databases. These are the two numbers we treat as ground truth — and the wheelbase does double duty as the scale for everything else.
No manufacturer publishes where the grips and pegs actually sit, yet those points define the riding triangle. Where a true side-profile photo of the bike exists, we mark five reference points on it — both axles, the seat, the grip and the peg — and convert pixels to millimetres using the known wheelbase (the distance between the axles) as the scale. From those, the grip and peg positions fall out in real-world millimetres.
Where no straight side-on photo exists, we don’t guess blindly: grip and peg heights are researched, and the horizontal reach is estimated from the geometry typical of that class of bike. Those bikes are flagged with a lower data-confidence rating.
Each bike’s calibrated posture is checked against how reviewers describe it — upright, sporty or committed — and the computed lean angle has to land in the matching band. Every bike page then carries a data-confidence badge so you can see at a glance whether its numbers are photo-calibrated or class-estimated.
Every bike is drawn in the same clean line style — one shared body template per type (naked, sport, cruiser, adventure, touring, dirt), anchored to that specific bike’s real seat, grip and peg points. Using the same template for every bike keeps the comparison about riding position, not paint jobs or marketing photos.
The rider is a stick model built from your height and inseam using standard body-proportion ratios, then posed by inverse kinematics — hips on the seat, hands on the grips, feet on the pegs — with the exact same posture solver applied to every bike. The riding angles you see — lean, knee bend, hip angle — are solved purely from those three points relative to the seat, which is why grip and peg calibration is what drives the posture; wheelbase only sets the drawing’s scale, and seat height places the bike on the ground and drives the feet-down reach. That is what makes two bikes genuinely comparable: only the machine changes, never the method. (Not sure of your inseam? Here’s how to measure it.)
Seat height and wheelbase are hard data; handlebar and footpeg geometry, and the ground-reach preview, are calibrated estimates. The feet-down preview assumes a typical seat width — a wide seat will spread your legs and cost you reach — and boots add sole height the model can’t see. Your weight matters too: a heavier rider compresses the suspension more, so the bike settles lower and you reach the ground a little better than the figures show; a lighter rider sits slightly higher. We deliberately don’t compute that — it depends on each bike’s springs and setup, which no maker publishes — so treat every figure as a strong guide, and always sit on the real bike before you buy.
Try it now — enter your height and inseam and see your fit on any bike, each with its own confidence badge.
Bottom line: seat height & wheelbase are hard data; handlebar/footpeg geometry and ground reach are calibrated estimates (see each bike’s data-confidence badge). Always sit on the real bike before you buy.