Cycling Guides
Cycling Aerodynamics: What Is CdA and How Many Watts Does Getting Low Save?
Above 30 km/h, 70–90% of resistance is air — mostly your body. CdA ranges, the cubic law, and the cost-effective order for cutting drag, with a free in-browser wind tunnel.
How Much Does Drafting Save? Science, Distance Decay, Safety
27–50% behind one rider, more mid-pack; benefits decay with every half wheel. Rotation logic and safety rules — verify it yourself in draft mode.
DIY Bike Fit at Home: Film a Phone Video, Measure 4 Joint Angles Free
A 5–10s side-view video, browser-local pose AI, four joint angles scored against reference ranges. Filming checklist and result guide.
Wind Tunnel Testing Cost — and 4 Affordable Alternatives
$500–1500/hr for the real thing. Chung method, aero sensors, CFD services and free online simulation — and why position comes before equipment.
AI Bike Fit Analysis: Upload a Riding Video, Measure Your Geometry
What is bike fit analysis? Upload a side-view riding video and AI measures your knee/hip/torso angles, comparing them to three-tier targets with saddle and front-end guidance + a PDF report. ±3°, ~30s, re-check anytime.
🚴 The Complete Cycling Pain Guide: Every Pain and Its Bike-Fit Cause
Where does it hurt? A head-to-toe pain map — neck/back/hands/hip/knee/saddle/foot — each mapped to its common setup cause and fix direction, with a deep-dive link for each. Most cycling pain is an adjustable setup problem.
Knee Pain From Cycling? Check Your Saddle Height First
What anterior vs posterior knee pain points to, the three-tier BDC knee angle ranges (140–150° / 135–145° / 130–133°), the limits of the LeMond formula, and safe ±3mm adjustment steps.
How to Set Saddle Height: 4 Methods Compared
Heel method, Hamley 109%, LeMond 0.883 and the BDC knee-angle method — principles, accuracy, error sources, and the "formula as start, knee angle as calibration" workflow.
What Torso Angle for TT / Aero Position?
Elite TT 4–12°, national elite 8–18°, road aggressive 30–40°; the ~14% power cost of going flat (24°→0°), the hip-angle constraint, and progressive lowering.
AI Bike Fitting vs In-Person Fitting: How to Choose
An honest capability-boundary table: what video fitting can do (±3° angles, directions, cheap re-checks) and what it can't (cleats, insoles, palpation, pain management).
Low Back Pain From Cycling? Start With Your Bike Fit
How excessive drop, reach and setback increase lumbar flexion; using torso + TDC hip angle to decide reach vs stack; and the role of core endurance training.
How to Choose Crank Length: Are Shorter Cranks Really Better?
Power barely changes (145 vs 170mm <1%), but shorter cranks open the hip angle and cut knee flexion (150mm hip/knee 45°/67° vs 180mm 51°/75°) — who should switch and what to re-adjust.
How to Set Up Cleats: Fore-Aft, Rotation & Float
Fore-aft doesn't affect power (rearward is a free win for the Achilles), rotation must follow your natural foot angle, and 0° fixed float is associated with knee injuries — medial/lateral knee pain: check cleats first.
Numb Hands From Cycling? Which Fingers Tell You Which Nerve
Pinky + ring = ulnar nerve; thumb + index + middle = median. 70% of riders on a 600km tour developed symptoms. Root cause is weight on the hands: saddle tilt/height, reach — full troubleshooting order.
Saddle Pain or Perineal Numbness? The 3-Step Sit-Bone Check
Sit bones carry load, soft tissue doesn't: width (spacing +20–30mm), tilt (0 to -2°), height calibration to stop rocking. Narrow-nose saddles measured at 2x+ the perineal pressure — never tough out numbness.
What's Different About Women's Bike Fitting?
Not "shrink and pink": how a wider pelvis, greater sit-bone spacing and more pelvic rotation change saddle width/shape and front-end height. Research shows bars below the saddle raise perineal pressure in women (Partin 2012). Measure by anatomy, not sex.
Neck & Shoulder Pain From Cycling? Start With Your Bike Fit
Affects up to 60% of riders: back-of-neck pain from too much drop/low bars forcing neck hyperextension, shoulder ache from over-long reach and shrugging. Raise the front, shorten reach, bend elbows, change hand positions.
Hip Pain From Cycling? Start With Saddle Height and Crank Length
Anterior pinching is usually a crushed top-dead-center hip angle (saddle too low/forward, cranks too long); lateral/one-sided ache is usually a saddle too high rocking. Opposite fixes — measure hip and knee angles.
Foot Pain & Hot Foot From Cycling? Start With Cleats and Shoes
Hot foot is usually cleats too far forward + narrow shoes compressing the metatarsal nerves. Move cleats back (10–20mm behind the ball), widen shoes, met pad; heel/Achilles pain is usually a too-high saddle.
Cycling Position Q&A: Comparing Positions & Adjusting Cleats by Feel
Endurance vs aggressive, tops/hoods/drops, drop and reach, saddle setback, climbing/flat, trainer differences; plus a full "where your foot hurts → how to adjust the cleat" reference. Dozens of common questions.