Mobility
Why a 13.8 kg chair carries 100 kg and a 25 kg chair carries 130
Rated capacity is not a marketing choice. It is tube wall, weld schedule, castor size and the test standard — which is why the lightest chair is rarely the strongest.
Buyers often ask why they cannot have the lightest chair and the highest capacity. The answer is that the two numbers are the output of the same set of structural decisions, and those decisions pull in opposite directions.
What sets the capacity figure
Rated capacity is decided by the weakest link in a chain of parts, not by the frame alone:
- Tube diameter and wall thickness — the main lever. Thicker wall, more capacity, more weight.
- Weld schedule — a joint is where a frame fails. More passes and post-weld treatment cost weight and money.
- Castor size and fork — small wheels transmit every kerb directly into the frame.
- The test standard behind the number — static load, fatigue cycles, and how the load is applied.
Our range, sorted by what it is built for
- 100 kg class: JYW002 at 13.8 kg, JYW5919 at 15 kg — both aluminium, both built to be lifted.
- 130 kg class: T100 at 15.5 kg (carbon), JYW5903 at 23.5 kg (steel), JYW001 at 25 kg (aluminium).
The jump from 100 kg to 130 kg is 30 % more load. Between JYW5919 and JYW5903 that 30 % costs 8.5 kg of chair. Between JYW5919 and T100 it costs 0.5 kg — because carbon carries the load without the mass.
The number buyers forget: the user, not the chair
A 100 kg rating means a 100 kg user on a flat floor, sitting down gently. Real use adds:
- Dynamic load from dropping into the seat — commonly 1.5 to 2× body weight at the moment of impact.
- A bag on the back, a shopping basket, a heavy coat.
- Kerb drops and potholes, which load the castors far beyond static weight.
This is why a 95 kg user on a 100 kg chair is not “within spec” in any meaningful sense. If your market runs heavy — and several do — sell the 130 kg class and stop apologising for the weight.
What to put in your listing
State the capacity and the chair weight, next to each other. A buyer who sees “13.8 kg / 100 kg” and “25 kg / 130 kg” understands the trade-off immediately. A buyer who sees only “lightweight!” will order the wrong one and blame the product.