The IRONMAN Leeds Bike Course: 180km of Rolling Yorkshire Roads

What we know about the course

The IRONMAN Leeds bike leg is 180km through the Yorkshire countryside, starting and finishing in the Roundhay Park area. For the 2025 edition the described structure was: an opening stretch of about 6km towards Shadwell, then three laps of roughly 55km. Do the maths: 6 + 165 doesn't make 180. The sources we checked don't close that gap, so the exact layout needs verifying against the official map when it's released. Don't build a kilometre-by-kilometre pacing plan on numbers that don't add up.

The elevation figures also differ by source: the technical sheet lists 1,800m of climbing, while other descriptions mention around 2,500m. The truth probably sits somewhere in between, but the practical message doesn't change: this is a hilly course, not a flat one. The most talked-about section is Black Hill Road, used in the 2018 Tour de Yorkshire. It's not an Alpine climb: it's the classic English hill, short or mid-length, repeated every lap, stacking up fatigue without you noticing.

The real problem: the surges

On a lap course with constant rolling terrain, the enemy isn't any single climb — it's the sum of the surges. Every time you come out of a corner or a ramp and push to get back up to speed, you burn glycogen. Do that a hundred times and you pay for it all on the marathon.

Practical rules:

• Ride the first lap defensively. Keep your power below your Ironman target for the first 60km. The race is decided in the second half of the bike and on the hilly marathon that follows.
• Cap your power on the climbs. Set a power ceiling for the ramps (roughly no more than 10-15% above your average target) and stick to it even when riders come past. At Leeds you'll pass plenty of them back on lap three.
• Descents and fast sections: eat and drink. On a rolling course the good opportunities to fuel are limited: use them.

Gearing and equipment

Without a verified official elevation profile for 2027, think in scenarios. With 1,800-2,500m of climbing over 180km, a generous cassette is the safe call: better to have one gear you never use than to grind a ramp at 50rpm. If you have both deep-section and mid-depth wheels, remember that Yorkshire weather brings wind and rain even in August: a mid-depth profile is often the right compromise. Pick tyres with good wet grip, not the absolute fastest: English country lanes after rain are unforgiving.

How to train for this course

• Find the hilliest routes in your area and do your long rides there, not on the flat.
• Work on repeated short climbs at a steady effort: 8-12 reps of 2-4 minutes at race power, with easy spinning recovery. It simulates the cumulative effect of the surges.
• Do at least two 5-hour long rides on rolling terrain holding your target power, followed by a 30-40 minute transition run on a slight incline. It's the most honest test of whether your pacing holds up.

The weather plan B

The event descriptions and common sense say the same thing: English weather can change in a few hours. Put a rain jacket and lightweight gloves in your bike bag, and practise putting them on in training, either on the move or in a quick stop. Losing two minutes to get dressed is nothing; riding 120km wet and cold can end your race.

Decision to make now: choose your cassette and wheels for a 2,500m-of-climbing scenario with possible rain. If the official 2027 map then shows an easier course, you'll just have extra margin.