Tool

Tube Picker

Tell us your wheels and tires — we'll tell you exactly what tubes (and valve length) to buy.

Rim depth: 50mm
Internal width: 20mm
Used on: Canyon Ultimate CF SLX, Canyon Ultimate CF SL
Width: 25mm
Type: Clincher

Tire-to-rim fit

Tire may sit too narrow on a 20mm internal rim (suggested 28–48mm).

Valve recommendation

Valve type
Presta
Recommended length
80mm
Rim depth
50mm

80mm valve recommended — or use a valve extender.

Recommended tubes

Continental Race 28 Light
Butyl (light)Presta • Fits 20–25mm65g
Race day on shallow/mid wheels
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Continental Race 28
Butyl (standard)Presta • Fits 20–25mm100g
Daily training
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Vittoria Competition Latex
LatexPresta • Fits 25–28mm75g
Race day — lowest rolling resistance
Find it
Tubolito S-Tubo Road
TPU (ultralight)Presta • Fits 18–32mm23g
Race day & spare in jersey pocket
Find it

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Quick rules of thumb

  • Valve length should be at least 15–20mm longer than your rim depth.
  • Tubeless setups don't need tubes day-to-day, but always carry a TPU spare.
  • TPU tubes (Tubolito, Aerothan, SmarTube) save 50–80g per wheel vs. butyl.
  • Latex tubes have the lowest rolling resistance but lose ~10–15 psi overnight.
  • Most modern road tires (25–32mm) work best on rims with 19–25mm internal width.

Frequently Asked Questions

What size inner tube do I need for my tires?

Match the tube to your tire width range and wheel diameter — for example a 700x25c tire needs a 700c tube rated for roughly 23–28mm. Select your wheelset and tire above and the tool returns the exact tube size and valve length.

How long should my valve stem be for deep-section wheels?

Your valve should be at least 15–20mm longer than the rim depth. A 65mm deep rim needs an 80mm valve, a 50mm rim needs a 60–70mm valve, and a shallow 30mm rim works with a standard 60mm valve.

Are TPU tubes worth it for triathlon?

Yes for most racers. TPU tubes such as Tubolito, Schwalbe Aerothan and RideNow save 50–80g per wheel, pack down to a fraction of the size of a butyl spare and roll marginally faster. Butyl remains the cheaper, more durable training option.

Do I need a tube if I run tubeless tires?

Yes — carry one as a spare. Sealant and a plug fix most punctures, but a large cut or a torn bead means fitting a tube to get home, so keep a compact TPU tube and a valve-core tool in your saddle bag.

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