What do I check on bikes, helmets and race numbers before the start?

Bike check (World Triathlon rule 5.3):

• A visual bike check happens before athletes go into the transition area. Check that the bike complies with the rules: UCI time trial rules for draft-illegal races, UCI road race rules for draft-legal races.
• Each registered athlete may check in one bike only, and must rack it before transition closes. Anyone who can't must tell the Head Referee.
• Disc brakes are allowed. Platform pedals are allowed if they have a quick-release mechanism.
• Not allowed: headphones, headsets, technical earplugs or smart helmets in or over the ears; glass containers; mirrors; and any non-compliant bike or part.

Helmet (rule 5.2 g):

• It must be approved by a recognised national testing authority, and must not be altered or have parts missing, including the chin strap or cloth cover.
• Number stickers go on the front and both sides, unaltered, with 1.5 cm clear around each. No other stickers are allowed.
• In draft-legal races only: no visors, and the helmet must not cover the ears.

Numbers (rule 2.9), age-groupers:

• The bib may be worn in a wetsuit swim but is forbidden in a non-wetsuit swim. It is mandatory on the run, visible on the front.
• Arm body marking goes as close to the shoulder as possible, and one calf is marked with gender and category (e.g. F25).
• Numbering items may not be altered without the Head Referee's approval.

Transition setup (rule 7.1): remove marks, towels and objects used to mark positions. Athletes aren't told when you do this.