650c Innertubes

650c Innertubes are ERTO 571 for 'Triathlon' sized wheels.
Innertubes can be made of Butyl or Latex.
Valves must be compatible with rims and pumps.
Most road bikes use Presta valves and most MTB's use Schrader or car valves but some use Presta.
Always carry a spare and it is good to keep several on the shelf.