Health and predictions

The Bikes tab opens with the bike's photo and, below it, a dashboard, like a car's: a row of warning lights, the two odometers and a line that says what to do. Further down are the upcoming inspections, one per component.

The app doesn't tell you "replace it": it tells you when to have each part inspected. Whether it needs changing is decided by whoever looks at it, you or your mechanic. That's CrankPal's rule: CrankPal forecasts, the mechanic diagnoses.

The dashboard#

The dashboard answers one question: what should I do now? The level is the one of the most urgent component, never an average, and it's read in time, because an inspection is planned in weeks, not kilometres.

Red is advice, not a block: the app doesn't stop you logging rides or doing anything else.

The lights are the component groups: drivetrain, brakes, wheels and tyres, steering and frame, contact points and, on e-bikes, the motor. Under the lights, the line gives the next inspection and the parts that set it, up to three, with "+N" if there are more. Next to it, two odometers: the bike's total and the kilometres since the last service.

Tap a light and its card opens: the part that sets the state and when it's due for inspection, how many components in that group are monitored, and Book an inspection. A light that's off doesn't mean everything is fine: it means no components have been recorded for that group yet.

Under the dashboard there's Book a service, which takes you to booking with the parts to check already ticked: see Workshops and bookings.

The upcoming inspections#

Under Upcoming inspections are the components, most urgent first. At first you see the ones that need attention; Show all components opens the full list, and at the bottom there's Add component.

Each row tells you three things:

• when the inspection is due, in words: "in 2 weeks", "in about 1 month". In the green, the row just says Ready;
• why: a bar that fills up towards the inspection and the three counters, with the one that comes first highlighted;
• what you can do: I inspected it and Book an inspection. On the row they appear from "in about 1 month" downwards; in the component's details they're always there.

Never a number of days: a due date to the exact day would be a precision the estimate doesn't have.

There's no health percentage for the part. It's an estimate of the life the part has left, and it's for whoever has the part in front of them: your mechanic sees it in the workshop system. What you need to know is when to look.

On bikes that are yours there's also the pencil for Edit component: name, brand, kilometres ridden, estimated lifespan, and Delete component if a part is no longer there.

With Maintenance alerts on, in Profile›Notifications, the app lets you know when a component enters the yellow and when it enters the red: one notification per bike, with the I inspected it and Book buttons. They open the app on that component, or on booking with the parts already chosen: nothing is recorded without you seeing it. Blue and green send nothing: they're information, not requests.

Three counters, whichever comes first#

For each component the app counts three things, from the last inspection or replacement (or from when the part was fitted, if there hasn't been one):

• Distance, from your rides or from the usage you declared;
• Hours ridden: we don't ask you for them, they're worked out from the distance and the average speed. The speed is the one measured on your rides; without rides, the one you declared when you added the bike; otherwise a typical value for the type of bike;
• Time: some parts age even when the bike isn't ridden, like brake fluid, tubeless sealant and tyres.

Each counter has its own expected life, and in the component's details it reads as "how much you've done of how much it lasts", with the deciding one highlighted. At the pace you ride, each one becomes a number of days, and the due date is the nearest. If the bike has neither rides nor declared usage, the app doesn't know your pace: the row shows the colour but not the time.

Expected life isn't the same for everyone. Four things make it longer or shorter:

• rain: from your rides with their weather, or from the percentage you declared until there are rides;
• where the bike is kept: indoors, outside under a roof, or outside in the open air;
• your weight, only if you've given consent to use it in your Profile;
• basic care, meaning how often you wash and lube: as soon as you log lubes and treatments, what you log is what counts.

As soon as real rides come in, measured data takes the place of declared data.

When you've inspected a part#

Tap the row, or I inspected it, and the component opens: the due date, the three counters and the question What did you do?, with three answers.

• I inspected it: all OK. The count starts again from zero and the next inspection comes at half the expected life. An inspection done early never brings the due date forward: whichever is later, the old due date or the new one, is the one that counts. Straight afterwards the app tells you when the next inspection will be and how the light changes.
• I inspected it and replaced it. The count starts again with the full life of the new part. You say when: Now, how many kilometres ago, or On a date. If you like, you also pick the part you fitted.
• Book an inspection at a workshop. It opens booking with that part already ticked.

Why half and not the whole expected life: a part that's fine today won't necessarily be fine after another whole life. If it keeps passing its inspections, the model learns that parts like it last longer, and the starting expected life goes up.

When the bike goes through the workshop, the mechanic records the outcome in the same place: OK, Worn (it still holds, but the next inspection comes soon), Needs replacing (the light stays red until the part is changed) or Replaced. You find it on the component under Last inspection, with the mechanic's note if they wrote one, and in the component's history.

Treatments. Some parts aren't replaced, they're looked after, and they have their own reminder. You log them from the part's row:

• Chain: I lubed it. The first time the app asks which lube you use and where the bike sleeps, because the interval changes with oil or wax, rain and storage. After a wet ride it reminds you.
• Tubeless sealant: I topped it up. Sealant dries out even when the bike isn't ridden, in the garage too: top-up and full replacement each have their own reminder, even if the bike stays in. If you run tubeless and the sealant isn't among the components, the app offers you Set up tubeless.
• Bearings: Bearings greased.
• Fork, shock and dropper post: Service done; for the e-bike motor, Motor serviced.
• Structural parts (frame, rigid fork, handlebar, stem, rigid seatpost, brake calipers): Inspection done.

Every treatment goes into the bike's logbook.

Usage, odometer and wear estimate#

How much you'll ride the bike you say when you add it, in the How you'll ride it step of the setup: the distance per month, the rain, where you'll keep it and how often you look after it. See Bikes and rides. Until rides come in, the prediction moves forward with that distance.

In Bikes›Bike settings›Usage and kilometres you type the odometer reading whenever you like: the reading corrects the total, and the difference from the kilometres already known goes to the components. On an e-bike you read it on the display.

Bikes added before the setup still have the wear estimate, in Bikes›Bike settings›Wear estimate: a slider with the bike's kilometres, then part by part whether it's the original or was replaced, and how many kilometres ago. At the end tap Apply the estimate, or Skip.

The Prediction tab#

The tab in the middle, with the CrankPal mark, shows where the estimate comes from for the chosen bike. On the left are the inputs: the bike with its components, the rides, the weather (how many rides were wet), what you log (treatments and the initial wear estimate) and the workshop. In the middle is the engine, which spins while the estimate updates. On the right is what comes out: the bike status and the component health, meaning how many need checking and how many soon will, plus the wheel sensor if the bike has one.

Each card that's missing something tells you how to fill it: connect Strava, log a ride, find a workshop. Tap the Prediction tab again to update the estimate.

At the bottom, in this tab as in Bikes, a few lines tell you where the numbers come from. One says what the timing rests on (Forecast timing based on: the sources of your rides, odometer readings or the usage you declared); another says which model the estimate comes from:

Where available, the average error appears next to it: "± 300 km" means that model's predictions, measured against real services, were off by three hundred kilometres on average. It's the most honest number on the screen, and it helps you judge how much margin to leave.

Common problems#