Triathlon equipment is shaped by both race rules and component specifications. The figures below cover authority-specific wetsuit thresholds, IRONMAN bike and transition requirements, and manufacturer measurements for training electronics and bicycle parts. Dates and event scope matter: these are rules or specifications, not a sales or ownership survey.
Contents
- Wetsuit thickness and coverage
- Water temperature thresholds
- Bike, brake, hydration, and drafting limits
- Transition bags and race labels
- Watch and heart-rate sensor specifications
- Drivetrain measurements
- Brake and equipment-fit figures
Wetsuit thickness and coverage
World Triathlon’s current FAQ sets equipment boundaries that depend on swim distance, water temperature, and athlete age. For swims up to 1,500 m, wetsuits are forbidden at 22°C or higher and mandatory at 15.9°C or lower. For swims of 1,501 m or longer, the corresponding upper threshold is 24.6°C, while the lower mandatory threshold remains 15.9°C. These thresholds are from the Triathlon FAQs, accessed in 2026.
For age-group athletes aged 60–64 and older, World Triathlon uses 24.6°C or higher as the wetsuit-forbidden threshold for all swim distances. At 15.9°C or lower, wetsuits are mandatory for those athletes across all swim distances. The race authority therefore has distinct rules for distance and age rather than one universal temperature cutoff.
World Triathlon also limits the suit itself. Maximum wetsuit thickness is 5 mm, and the overlapping section of a two-piece wetsuit may not exceed 5 mm. When a wetsuit is permitted, it may cover 2 arms, but it may not cover 2 hands. It may not cover 1 face or 2 feet. These are coverage and construction limits, not recommendations about a particular brand or model.
Water temperature thresholds
The 2025 USA Triathlon Sprint and Olympic Distance National Championships guidance gives a different event-specific frame. The expected race-water temperature range was 64–71°F. At that event, wetsuits were forbidden at 76.2°F or above and mandatory at 60.6°F or below. The figures come from 2025 USA Triathlon Sprint and Olympic Distance National Championships race guidance.
The Celsius and Fahrenheit values should not be treated as a single global rulebook. World Triathlon’s current FAQ describes its own thresholds, while USA Triathlon’s numbers describe the 2025 Sprint and Olympic Distance Nationals. A local race can publish additional instructions, so athletes should check the event authority and the measured race-day temperature.
World Triathlon says the head referee announces the official water temperature and wetsuit decision 1 hour before race start. That timing makes the final decision a race-day operational detail, even when the threshold is known in advance.
| Authority or event guidance | Wetsuit mandatory at or below | Wetsuit forbidden at or above | Scope |
|---|---|---|---|
| World Triathlon, swim up to 1,500 m | 15.9°C | 22°C | Current FAQ, accessed 2026 |
| World Triathlon, swim 1,501 m or longer | 15.9°C | 24.6°C | Current FAQ, accessed 2026 |
| World Triathlon, age-group 60–64 and older | 15.9°C | 24.6°C | All swim distances |
| USA Triathlon Nationals | 60.6°F | 76.2°F | 2025 Sprint and Olympic Distance Nationals |
World Triathlon’s cold-water aquathlon variant below 22°C uses a 1 km swim followed by a 5 km run and requires wetsuits. That figure comes from the Triathlon FAQs and the World Triathlon aquathlon page, with the aquathlon format and threshold applying to that variant rather than to every triathlon.
Bike, brake, hydration, and drafting limits
The 2025 IRONMAN Competition Rules, effective February 25, 2025, require 1 working brake on each of a bicycle’s 2 wheels. The rules also prohibit 1 tandem bicycle, 1 fixed-gear bicycle, 1 recumbent bicycle, and 1 bicycle fairing in the race. They additionally prohibit 1 add-on device designed exclusively to reduce cycling resistance. These figures describe 2025 Competition Rules, not a general equipment law for all triathlon events.
Hydration limits are quantified too. Front-mounted bicycle bottles and hydration systems have a combined cap of 2 liters. No more than 2 rear-mounted water bottles are allowed, excluding bottles inside the frame, and each rear-mounted bottle is capped at 1 liter. In other words, the rule distinguishes external rear bottles from bottles located inside the frame.
IRONMAN’s 2025 drafting rules define the clear-space target as 6 bike lengths behind the leading bicycle. This is a race-positioning measurement, not a recommended frame size or wheelbase. Athletes should read the complete event rules because equipment legality and drafting enforcement operate together on course.
Transition bags and race labels
The 2025 IRONMAN 70.3 Tours athlete guide gives a useful inventory example for transition organization. The race package includes 2 transition bags: a blue bag for bike gear and a red bag for run gear. It also includes 1 white street-wear bag and 1 official swim cap. These quantities are specific to the Athlete guide 2025 - IRONMAN 70.3 Tours Métropole- Loire Valley.
The guide specifies 3 gear-bag stickers for the run, bike, and street-wear bags. It adds 1 sticker for the bicycle seatpost, 1 for the front of the helmet, and 1 for the athlete wristband. The race-kit sticker sheet includes 2 additional stickers. Taken together, the listed sheet contains 8 stickers: 3 gear-bag stickers, 3 identification stickers for the seatpost, helmet, and wristband, plus 2 additional stickers. The count is a direct sum of the guide’s listed quantities and is included only to make the inventory easier to check.
These bag colors and label counts should be treated as event instructions, not universal triathlon standards. A race guide can change the bag system, labeling locations, or included items.
Watch and heart-rate sensor specifications
Garmin’s Forerunner 965 specification lists dimensions of 47.1 × 47.1 × 13.2 mm, a weight of 53 g, a 1.4-inch AMOLED display, and a resolution of 454 × 454 pixels. It has a 5 ATM swim water rating, described as equivalent to pressure at 50 m depth. These product figures are from Garmin’s Forerunner 965 Watch Owner’s Manual, accessed in 2026.
The April 2026 Garmin owner manual lists several Forerunner 965 battery estimates. Smartwatch mode is rated for up to 23 days. GPS-only activity mode with wrist heart rate is rated for up to 31 hours; Auto Select GPS with wrist heart rate for up to 22 hours; and all-systems multi-band GPS with wrist heart rate for up to 19 hours. With music, the ratings are up to 10.5 hours for GPS-only activity with wrist heart rate and 8.5 hours for all-systems multi-band GPS with wrist heart rate. UltraTrac mode with wrist heart rate is rated for up to 34 hours.
| Forerunner 965 mode | Rated maximum |
|---|---|
| Smartwatch | 23 days |
| GPS-only activity plus wrist heart rate | 31 hours |
| Auto Select GPS plus wrist heart rate | 22 hours |
| All-systems multi-band GPS plus wrist heart rate | 19 hours |
| GPS-only activity, wrist heart rate, and music | 10.5 hours |
| All-systems multi-band GPS, wrist heart rate, and music | 8.5 hours |
| UltraTrac plus wrist heart rate | 34 hours |
The Garmin HRM-Tri sensor uses a user-replaceable CR2032 battery rated at 3 V. Garmin’s February 2024 manual rates the battery for up to 10 months of triathlon training at approximately 1 hour per day. The same HRM-Swim and HRM-Tri specifications list an operating temperature range of −10°C to 50°C and a wireless specification of 2.4 GHz at +1 dBm nominal. The HRM-Tri figures are from February 2024 and are retained with that date.
Drivetrain measurements
Shimano’s 2025–2026 DURA-ACE FC-R9200 specification uses 12 rear speeds. The 2025–2026 Specifications, version 3.5 dated April 15, 2026, lists 4 chainring combinations: 46-36T, 50-34T, 52-36T, and 54-40T.
The FC-R9200 chain line is 44.5 mm, its pitch-circle diameter is 110 mm, and it has 4 spider or gear arms. Shimano lists 5 crank-arm lengths from 160 mm through 175 mm. For threaded bottom-bracket shells, the specification lists 2 widths: 68 mm and 70 mm.
Average crankset weight varies by listed chainring combination. The 46-36T version is 693 g, the 50-34T version is 685 g, the 52-36T version is 692 g, and the 54-40T version is 714 g. These are manufacturer average weights, not independent measurements of every retail unit.
| FC-R9200 chainrings | Average crankset weight |
|---|---|
| 46-36T | 693 g |
| 50-34T | 685 g |
| 52-36T | 692 g |
| 54-40T | 714 g |
Brake and equipment-fit figures
Shimano’s current DURA-ACE BR-R9200 product specification gives the caliper a maximum compatible tire size of 28C. The figure appears in the DURA-ACE DUAL-PIVOT BRAKE CALIPER specification accessed in 2026.
The 28C figure is a component compatibility limit for that caliper specification. It should not be generalized to every DURA-ACE brake, every wheel, or every bicycle frame. Likewise, the FC-R9200 dimensions, weights, chainring combinations, and shell widths describe Shimano’s cited version 3.5 handbook dated April 15, 2026. Manufacturer specifications can change with revisions, so the version and measurement dates remain part of the equipment statistics.