Bicycle tyres always lose a little air over time - even without a puncture. Therefore, check the pressure regularly and inflate if necessary.
In this compact guide, we explain step by step how to inflate a tube with a Sclaverand valve correctly and avoid typical mistakes straight away.
What is special about the Sclaverand valve?
The valve is narrow and is opened and closed at the top using a small knurled nut. It seals reliably as soon as there is pressure in the hose - which is why the correct sequence is important when pumping.
This is what the valve looks like:
- Narrow valve for small rim bores
- Top knurled nut for opening/closing
- Valve cap protects against dirt (optional, but useful)
Prepare the pump
Many floor pumps can use Presta directly. If your pump is only for car valves (Schrader), you will need a Presta adapter.
Inflate the air Step 1: Open the valve
- Remove the valve cap.
- Knurled nut anti-clockwise loosen (do not unscrew completely).
- Briefly press the valve pin once until it hisses (valve is free).
Inflate the air Step 2: Attach the pump head
- Pump head straight and attach firmly
- If your pump has a locking lever, lock it now
- Does it whistle on your head? Then it's not sitting properly - put it on again
Inflating the air Step 3: Inflate
Pump up to the desired pressure. The ideal air pressure depends on tyre width, surface, system weight (bike + rider + luggage) and comfort. The following table gives a rough guide. Alternatively, you can use an air pressure calculator
| Tyre width | Front (bar) | Rear (bar) |
| 25 mm (road) | 5,5-7,0 | 6,0-7,5 |
| 28-32 mm (road/all-road) | 4,0-5,8 | 4,4-6,2 |
| 38-45 mm (Gravel) | 2,2-3,6 | 2,5-3,9 |
| 2.3" / ≈58 mm (MTB) | 1,2-2,0 | 1,4-2,2 |
The table shows guide values that you can use as a starting point (typical for everyday to sports use). Usually +0.2 to +0.4 bar at the rear compared to the front.
Inflate the air Step 4: Remove the pump head and close the valve
- Release lever
- Pull the head off quickly and straight. A short hiss is normal; air usually escapes from the pump head, not from the tyre
- Knurled nut clockwise Close hand-tight (do not turn too tightly)
- Replace the valve cap (if present)
Common problems (and quick solutions)
Tyres do not become hard
Check whether one of the most common sources of error is present.
- Knurled nut really loosened?
- Valve pin pressed briefly (hiss test)?
- Pump head correctly locked?
- Is the seal in the pump head dirty/defective?
A lot of air escapes during extraction
- Do not pull off the pump head at an angle, but straight
- Pull off the pump head quickly
- Close the knurled nut immediately afterwards
Quick guide to inflating tyres
- Cap off
- Loosen knurled nut
- Press valve pin briefly (hiss)
- Attach + lock pump head
- Pumps
- Head off, knurled nut closed, cap on
Tip: Practise inflating at home before you go on tour. This will help you avoid stress on the road.
Sandra Schuberth
Editor
