A motorcycle jacket and trousers are sized with a different logic from everyday clothes. The aim is not only comfort; it is for the elbow, shoulder, knee and hip protectors to stay exactly over the joint in a crash. A loose jacket rides up in a slide and the protector slips off the shoulder; a tight jacket, on the other hand, pulls on your arms in the riding position and tires you on a long trip. In this guide we explain which measurements to take, how to read European size numbers and why you should do the try-on as if you were on the motorcycle.
Which measurements should you take?
Take the following measurements with a tailor's tape measure and a helper. Take the measurements wearing the clothing you will wear under the jacket (for a winter jacket, with a fleece or thermal layer).
- Chest circumference: arms at your sides, just below the armpits, at the widest part of the chest.
- Waist circumference: at the height where you wear the trousers, generally a little below the navel.
- Hip circumference: at the widest part of the hips.
- Arm length: extend your arm forward with a slight bend; measure from the tip of the shoulder over the elbow to the wrist.
- Inseam: without shoes, from the crotch to the heel along the inside edge of the leg.
- Height: some brands give a height range in the size chart too.
How to read European size numbers
Many European brands use numerical sizes such as 46, 48, 50, 52, 54, 56 rather than letters for jackets and trousers. These numbers roughly reflect half the chest circumference (for jackets) or, with a certain ratio, the waist circumference (for trousers); that is, a size 50 jacket is designed for a chest circumference of roughly 100 cm. But this gives only an idea: there is a 2–4 cm shift from brand to brand, and some brands cut a sporty fit narrow.
| Numerical size (men's) | Approximate letter equivalent |
|---|---|
| 46 | XS |
| 48 | S |
| 50 | M |
| 52 | L |
| 54 | XL |
| 56 | XXL |
This correspondence is a commonly used approximation, not a standard. In women's cuts the numbers are different (mostly 38, 40, 42); for women riders you can see women's-cut products on the women's gear page. Always look at the centimetre values in the brand's own chart.
Fit types: sports, touring, city
- Sports fit: cut close to the body, with the arms sewn curved forward. Narrow when standing, comfortable in the leaning-forward riding position. Leather jackets and leather suits are generally in this fit.
- Touring and adventure fit: loose enough to take a thermal layer inside, with longer arms and back. Comfortable in an upright seat; can be narrowed with adjustable belts and sleeve straps.
- City fit: a look close to everyday clothing, medium looseness. Check whether there are protector pockets and whether the protectors come fitted.
6 checks when trying on a jacket
- Riding position: extend your arms forward as if holding the handlebar. The sleeves should cover down to the wrist, and the fabric on the back should not ride up from your waist.
- Shoulder protector: the protector should be exactly over the tip of the shoulder. If it slides towards your neck when you raise your arm, the size is too big or the fit is not right.
- Elbow protector: when you bend your arm the protector should cover the tip of the elbow and not slide onto the forearm. In many jackets the protector position can be changed with the adjustment strap inside the sleeve.
- Back: when you lean forward the hem of the jacket should stay above the waist of the trousers; no wind should get in between. If there is one, try the jacket-to-trousers connecting zip.
- Chest and abdomen: with the zip closed you should be able to breathe in and out, with room left to wear an inner layer.
- Collar: with a helmet on, the collar should not squeeze your neck, and you should be able to turn your head left and right comfortably.
5 checks when trying on trousers
- Knee protector: not standing, but when your knee is bent in the seated position, the protector should be exactly over the kneecap. In many trousers the protector height is adjustable.
- Leg length: in the riding position the trouser leg rides up. The right length is one that covers the boot shaft when standing and does not leave the ankle exposed when seated.
- Waist: when you lean forward the trousers should not slide down at the back. The rear waist height is greater in sports cuts.
- Hip protector: if fitted, it should be over the outer bony prominence of the hip.
- Boot compatibility: decide whether the trouser leg will go inside or outside the boot, and do the try-on with the boots. The boot selection guide will help here.
Protectors and standards
The joint protectors in the jacket and trousers are tested to EN 1621-1 and the back protector to EN 1621-2; level 2 transmits less force, meaning it protects better. The garment itself is labelled according to the EN 17092 classes (AAA, AA, A, B, C). For details, see the protection levels guide. The point you need to know when choosing a size is this: even the highest-class label is useless if the protector is in the wrong place. Fit first, label second.
If your jacket has a back-protector pocket but it is empty or has only a thin foam in it, fitting a suitable back protector is a good upgrade. Separately worn knee and elbow protectors are also an option for short trips in ordinary clothes.
Size allowance by season
- Summer mesh jacket: choose it close to the body. If the mesh fabric is loose it flaps in the wind and the protectors shift out of position. Summer jacket options.
- Four-season jacket: try it on with the liner fitted. If it is loose when the liner is removed, see whether it can be narrowed with the adjustment straps. Four-season jackets.
- Trousers: if you will wear thermal leggings under them, do the try-on with them. Trouser options.
If you are between two sizes
If your chest and waist measurements point to different sizes, choose the jacket by the chest and the trousers by the waist. If you are between two sizes: think of the smaller in summer and leather garments, and the larger in winter and touring garments; but the decision should be made by whether the protectors stay in place. Models with many adjustment straps are more flexible at bridging the gap between sizes.
Staying flexible between summer and winter
Because of Turkey's climate, many riders try to get through the whole year with a single jacket. In this case choosing the size becomes even more critical: if you will use a four-season jacket without the liner in summer and with the liner and a fleece underneath in winter, you must do the try-on in both states. Without the liner the protectors must stay in place, and with the liner you must be able to extend your arms forward. Adjustment straps, waist laces and the hook-and-loop on the sleeve cuffs bridge the difference between these two states; in jackets with few adjustment points this flexibility is limited.
The situation is similar with trousers. If you will wear thermal leggings under winter trousers, assess the waist and hip measurement accordingly. If in summer you prefer mesh trousers or protective motorcycle jeans, choose a model where the knee protector is adjustable. Buying the jacket and trousers as two sets for separate seasons raises the budget, but gives better fit and comfort in both sets. Whichever combination, the unchanging criteria are that the protectors stay in place and that the wrists, waist and ankles are not left exposed in the riding position.
Conclusion
For jacket and trouser size, take your chest, waist and inseam measurements, find your starting size from the brand's chart, then be sure to try it in the riding position. If the wrists are not exposed with your arms forward, and the protector stays over the knee when it is bent, you have found the right size. For the overall gear budget, take a look at the gear guide.
Frequently asked questions
Should a motorcycle jacket be bought one size bigger?
No, as a rule it should not. A loose jacket rides up in a crash and the protectors slide off the joint. Try a winter jacket on with the layer you will wear inside it, and if the protectors stay in place, take that size.
What does size 50 mean in a jacket?
In European numerical sizes, 50 generally corresponds to size M and a chest circumference of about 100 cm. The exact value varies from brand to brand; look at the chart.
The knee protector slides below the knee; what should I do?
First check the protector height adjustment in the trousers. If there is no adjustment or it is not enough, the trousers are too long for your height; try a shorter length or a different fit.
Should the jacket and trousers be the same brand?
It is not mandatory, but with products of the same brand the connecting zip is compatible. This zip prevents the jacket riding up during a slide.