Track Day Fuel Calculation.

Fuel is the one consumable on your bike that is heavy, sits high, and changes through the session. Get the load wrong in either direction and it costs you — just in opposite ways. Under-fuel and you risk the engine starving on the final lap, which on a fast bike in a group is genuinely dangerous, not just embarrassing. Over-fuel and you carry kilograms of dead weight perched above the tank, blunting every direction change for no benefit.

The goal is simple: carry enough to finish the session with a sensible reserve, and not a drop more than you have a reason to. That means knowing two things — how long you’re out, and how fast your bike drinks. The first you control. The second you measure. Everything in this guide is about turning those two numbers into a confident fuel level before you head out.

The whole calculation is two short lines. The first gives you the volume of fuel to put in; the second tells you what that fuel weighs so you can judge the handling cost.

• Litres= session duration (min) × burn rate (L/min) + safety margin (L)
• Weight (kg)= litres × 0.74 (petrol density, about 0.74 kg per litre)

That’s it. Three inputs — duration, burn rate and margin — and the output is a target fuel volume plus the weight penalty you’re accepting. The only one that takes any thought is burn rate, because it isn’t a fixed property of the bike: it moves with pace, track and even temperature. The next section is about pinning it down. This is exactly the maths the Apex Wizard Fuel Managerruns for you, but it’s worth understanding by hand so the slider positions mean something.

Burn rate is the number everyone wants a single answer for, and there isn’t one. A sportbike at track pace typically burns somewhere around 0.5 to 1.0 litres per minute, but where you land in that window depends on real variables:

• The bike. A 1000 cc superbike at full noise drinks far harder than a 400 or a middleweight twin.
• Your pace. A novice session at 70% throttle and a fast group chasing lap records are not the same draw, even on identical machines.
• The track.A power circuit with long straights at wide-open throttle burns more than a tight, technical layout where you’re off the gas more of the lap.

Because of all that, a generic figure is only a starting point. The honest method is to measure your own: note how much fuel you put in, run a known session length, then refill and record what went back in. Divide litres used by minutes ridden and you have a burn rate that’s true for your bike, your pace and that track. Do it a few times and a tight, trustworthy number emerges.

Take a typical club track-day group: 20 minutes out, on a 1000 cc sportbike, at a solid intermediate pace. Suppose you’ve measured your burn rate at 0.8 L/min on this track. Run the numbers:

• Fuel needed= 20 min × 0.8 L/min + 1.5 L margin = 17.5 L
• Weight = 17.5 L × 0.74 = about 13 kg

So roughly 17.5 litres covers the session with a 1.5 L reserve, and it adds about 13 kg of fuel to the bike. Now flex the inputs to see how sensitive the answer is. Drop to a milder 0.6 L/min and the same 20 minutes plus margin needs only 13.5 L — nearly 3 kg lighter. Push to a hard 1.0 L/min on a power circuit and you’re at 21.5 L, which may be more than a small tank holds for a single session.

That spread is the whole point. The difference between guessing “half a tank” and calculating from a measured burn rate is several kilograms of fuel either carried needlessly or missing when you need it. The same discipline that makes your tire-pressure targets repeatable applies here: measure, record, decide.

Fuel isn’t just a number on a gauge — it’s mass, and mass in the wrong place changes how the bike behaves. The tank sits high and forward, so fuel weight raises the bike’s centre of mass and shifts balance toward the front. A brimmed tank makes the bike feel top-heavy and lazy to flick from side to side; as it empties through the session, the bike gets lighter and more eager, and your braking markers and turn-in feel subtly shift.

That’s why a full tank on a 20-minute session is usually the wrong call: you’re carrying the worst-handling state of the bike for longer than you need to, with litres you’ll never burn. Carrying only what the session requires keeps the mass lower and the handling more consistent end to end.

Fuel load also feeds your chassis baseline. If you set sagwith a full tank and then ride sessions near empty, your effective ride height and front-to-rear balance drift as the fuel burns off. It’s the same cause-and-effect that turns a stable bike into one that runs wide— a balance change you didn’t consciously make. Knowing roughly where your fuel level sits when you set your baseline keeps the rest of your setup honest. The deeper picture lives in the suspension tuning guide.

The single biggest upgrade to your fuel planning is keeping a record. Every session, note three things: minutes ridden, litres burned, and how hard you pushed. Over a handful of sessions you build a personal burn-rate table — one number for a relaxed warm-up group, a higher one for the fast session, maybe a track-by-track breakdown if you ride several circuits.

With that history, fuel planning stops being guesswork. You can trim your margin because you trust the measurement underneath it, and you arrive at each track knowing roughly what to put in before the first session even starts. The same logging habit that makes your suspension changes traceable makes your fuel load predictable.

• Log litres in and litres outper session, not per day — pace varies between groups.
• Note the track and conditions, so a hot, fast day and a cool, technical one don’t get averaged together.
• Keep your margin until the data earns its removal— tighten it only when several clean sessions agree.

Fuel is just one more setup variable worth treating with the same rigor as pressures and clickers. Browse the full guides library for the rest, and if you ride a Yamaha or a Ducati, the model pages under Yamaha setup and Ducati setup give you a starting point to log against.