Measuring your thigh while seated with riding jeans and boots on is the single most critical step for properly fitting motorcycle chaps, since the waist is adjustable but the thigh is not.
For the full breakdown, see our best Motorcycle Chaps guide.
Why Thigh Measurement Comes First
The thigh dictating the size because it has zero adjustment. A thigh measurement taken while standing flat-footed will yield chaps that bind painfully the moment you swing a leg over the bike. Sit in a chair with your knees bent at 90 degrees — that replicates the riding position — and measure the circumference at the thickest part of the thigh, typically right near the groin. Wear the same riding jeans and any cold-weather base layers you plan to use. The fit should be snug enough that you can slide one flat hand between the leather and your jeans with resistance; any looser and the leather will flap and shift.
Measuring Waist and Length Correctly
The waist is straightforward: measure around your natural waistline, inline with your navel, right where the belt sits. Eagle Leather confirms the waist adjusts 2 inches up or down in the front and up to 6 inches in the back via rear laces, so exact precision here matters less than the thigh. For length, stand with your riding boots on and measure the outseam from the top of your belt to the floor. Mark the leather so it sits just above the floor while standing, then sit on the bike — or do a deep squat — and confirm your ankle stays covered. Chaps ride up roughly an inch when seated, so cut 1 inch longer than that seated mark.
| Brand & Size | Waist Range (in) | Thigh (in) |
|---|---|---|
| Eagle Leather S | 31–39 | 23 |
| Eagle Leather M | 33–41 | 24 |
| Eagle Leather L | 35–43 | 25 |
| RevZilla Street & Steel SM | 31–35 | 21.5 |
| RevZilla Street & Steel MD | 34–38 | 23 |
| RevZilla Street & Steel LG | 37–41 | 24.5 |
| Fox Creek (Custom) | Any | Any |
Common Mistakes That Ruin the Fit
The most frequent error is measuring the thigh while standing — the measurement is always smaller than the seated measurement, and the resulting chaps will bind when you ride. Skipping base layers when sizing for winter gear is equally costly; chaps that fit perfectly over thin summer jeans become unwearable over thermals. Cutting length based solely on the standing mark leaves your ankles exposed when you’re actually on the bike, especially if your bike has mid-controls that create a sharper knee bend and more upward ride. If you’re between sizes on the thigh chart, always choose the larger size for safety. Chaps that are too tight at the thigh bind when sitting; chaps that are too loose flap dangerously at speed.
FAQs
Should I size up or down when my measurement falls between chart sizes?
Always size up when your thigh measurement falls between sizes. Chaps that are slightly roomy can be cinched tighter at the waist, but tight chaps at the thigh will bind painfully when you sit on the bike and can restrict leg movement for shifting or braking.
Can I trim the length on chaps that are too long?
Yes, leather chaps are designed to be trimmed. Mark the desired length while seated on your bike, leave 1 extra inch for ride-up, and cut with sharp scissors. The raw edge will not fray because leather does not unravel.
Do all chap brands use the same sizing chart?
No, each brand uses its own measurements even though all are in inches. Eagle Leather, Fox Creek Leather, and RevZilla’s Street & Steel line each have different thigh and waist values per size. Always check the specific brand’s chart before ordering.
References & Sources
- Eagle Leather. Chap Sizing Guide Details waist adjustability and standard size measurements.