Route Builder

Click the map to add waypoints, drag them to move, right-click one to remove it. Export a route for the trainer app, or a GPX for your bike computer (Garmin, Wahoo, Karoo, …).

Route

Roads for Find a place

Import

A GPX track (elevation looked up when it has none) or a route CSV. It replaces the drawn route.

Shaping

Point every (m)

Smoothing (m)

Grade limit (%)

Map elevation is noisy (±several meters): smoothing over 100–300 m gives grades that feel like the road.

Workout

Name Description

Rolling resistance

Air (ρ·CdA, kg/m)

Estimate

Steady power (W)

Rider + bike (kg)

–distance

–time at that power

–climbing

–descent

–steepest

–steepest down

Map tiles for the app's map page

The area around the route from the map shown here, darkened, at the scales the app's map page shows it (some 30–60 tiles, a few hundred KB in the CSV). Without them the page shows the route alone.

Run it with trainer --workout route.csv, or drop the file on the trainer's window.

The GPX is a track with elevation for a cycling computer (Garmin Edge, Wahoo ELEMNT, Hammerhead Karoo, Bryton, …) or for Strava, Komoot and RideWithGPS.

Rolling resistance (Crr)

How hard the tyres roll on the road: the force is Crr × weight (rider + bike), about 3.3 N at 0.004 and 84 kg, the same at any speed. It belongs to the road and the tyres, so choose it for the surface this route follows.

Surface and tyres	Crr
Velodrome, race tyres	0.0025
Smooth asphalt, good road tyres	0.004
Average or worn asphalt	0.005
Rough chipseal	0.007
Hard gravel	0.010
Cobbles, dirt	0.015

It matters most on flat and gentle roads at low speed; on a climb the grade outweighs it. The trainer gets it with the grade (simulation), and the speed on the road follows from it. Tacx trainers controlled through FE-C take at most 0.0127.

Air resistance (ρ·CdA)

The drag of the air: the force is ½ × ρ·CdA × speed², so it grows fast with speed. Above about 25 km/h on the flat it is most of what you push against; on a climb it hardly counts.

CdA (m²) is the rider's frontal area times the drag coefficient: how you sit on the bike. ρ (kg/m³) is the air's density: thinner high up and when it is hot.

Altitude (m)

Temperature (°C)

Position	CdA	ρ·CdA

A taller or heavier rider has a larger CdA than the typical values here. The trainer gets ρ·CdA with the grade (simulation), and the speed on the road follows from it.

The route on your bike computer

Export GPX gives a standard GPX 1.1 track: the route as drawn, a point every "Point every" meters, with the smoothed elevation, so the computer shows the same climbs and grades as the profile here. Any device or app that takes GPX can follow it.

Device or app	Where to load it
Garmin Edge	Garmin Connect: Training & Planning → Courses → Import, then send it to the device
Wahoo ELEMNT	ELEMNT app: Routes → import the file, or open the file with the app on the phone
Hammerhead Karoo	Hammerhead dashboard: Routes → Import, it syncs to the Karoo
Bryton, Coros, iGPSPORT, …	The brand's phone app, in its routes or courses section
Strava, Komoot, RideWithGPS	Import the GPX as a route, then sync it to the computer from there