Valve type
Presta valve (SV): stem size, locknut, cores and pump heads
How to recognize a Presta valve, its nominal 6 mm stem and locknut, removable cores and core tools, and the pump heads and chucks makers list for it.
Also listed as Sclaverand, SV, French valve
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Short answer
A Presta valve is the thin one with a small locknut at the top that you unthread before pumping. Park Tool gives the stem as nominally 6 mm. Some Presta cores unscrew (look for two wrench flats), which is why a core can come out with a pump head. Confirm yours with the valve finder.
Key facts
- How to recognize it
- A thin stem with a small locknut at the top that must be unthreaded before air can enter the tube. Park Tool suggests tapping the valve after unthreading so it is not stuck.[1][2]
- Stem diameter
- Nominally 6 mm, thinner than a Schrader stem (Park Tool).[1]Park Tool gives no tolerance.
- Valve core
- Some Presta valves have removable cores, recognizable by two wrench flats at the end of the valve; not all are removable. Lezyne attributes many cores coming out with the pump head to cores not tightened enough at assembly, and advises checking that cores are tight.[1][3][4]Lezyne's explanation is a maker's, not independent data.
- Pump heads makers list
- SILCA states its Pocket Impero pumps work only with Presta. Lezyne lists its Dual Valve floor-pump head for Presta, Dunlop and Schrader, and says its Slip Fit head on hand pumps and CO2 systems is Presta-only.[5][6]
- Adapters and extenders
- Park Tool's VC-1 fits Presta valve extenders that have 5 mm wrench flats. Lezyne warns that its Speed Chuck is for valve extenders only and will fail on a regular threaded Presta valve.[3][4]The VC-1 statement covers extenders with 5 mm flats only.
- Schwalbe code
- SV (Sclaverand)[7]
- Adding sealant
- Tubolito says its Presta (SV) valve cores are glued in, so on its tubes only the Schrader (AV) valves have removable cores that accept sealant.[8]Applies to Tubolito tubes only.
- Heat caution
- Not confirmedFor plastic valves on TPU tubes, see the TPU tube valve page.
- Tools
- Park Tool's VC-1 removes and installs removable Presta cores. Lezyne's ABS button releases hose pressure so the chuck can come off without unthreading the core.[3][6]
- Not confirmed
- Park Tool gives no tolerance for the nominal 6 mm stem, and no source we read says which bikes come with Presta valves.[1]
Watch out for
- Lezyne's Speed Chuck is for valve extenders only and fails on a regular threaded Presta valve.
- Not every Presta core is removable; look for two wrench flats.
- Tubolito glues its Presta cores in, so sealant goes through its Schrader version instead.
- SILCA's Pocket Impero works only with Presta, so it will not take a Schrader valve.
What fits
Product details below are the seller's own description unless a source is shown. Pick the variant named for each item.
Mini pump
Lezyne Pocket Drive mini pump (160 psi, ABS Flex Hose)Choose the light gray Pocket Drive; it is the only version listed.
Lezyne lists an ABS Flex Hose for Presta and Schrader valves.
Floor pump
Park Tool PFP‑10 Home Mechanic floor pump (160 psi)Choose the PFP-10; it is the only version listed.
Park Tool lists a head for Presta and Schrader valves.
Electric pump
CYCPLUS AS2 Pro electric mini pump (120 psi, Presta and Schrader)Choose the AS2 Pro in black, not the AS2, AS2 Pro Max or AS2 Ultra.
CYCPLUS says it switches between Presta and Schrader without extra parts.
Multitool with Presta core tool
Topeak Hexus X multitool (21 functions, chain tool, tire levers)Choose the Hexus X (TT2573B).
Topeak lists a Presta core tool among its functions.
Next: Presta vs Schrader vs Dunlop, Presta core came out with the pump? and dual-valve pump heads explained.
Questions
Why did my Presta valve core come out with the pump head?
Lezyne attributes many such cases to cores not tightened enough at assembly and advises checking that cores are tight. A removable core has two wrench flats. See Presta core came out with the pump?.[4][1]
How do I know if my Presta core is removable?
Park Tool says removable Presta cores have two wrench flats at the end of the valve, and that not all Presta cores are removable.[1][3]
Can I use a Lezyne Speed Chuck on a Presta valve?
Only on a valve extender. Lezyne says the Speed Chuck will fail on a regular threaded Presta valve.[4]