What it is

A real road, seven riders, your turn on the front

Chainy is the Clifton chaingang loop near York, 48 km of real lanes, built from the Environment Agency's laser survey so the climbs, the dips and the bridges are the ones that are there. Seven other riders roll round in two lines. You're the eighth.

The chaingang, done properly

A fast line going up, a recovering line coming back. Do your turn on the front, pull over, drift back, go across onto the last rider when the one who just passed you flashes red. Nobody holds you up, and nobody tows you. The one time the bunch waits is when you stop pedalling: then it stops too, re-forms round you and waits for your legs.

Your watts decide where you sit

Push and you close up on the wheel. Ease and you drift back. Keep easing and you're off the back. Stop pedalling and the whole thing stops and waits for your legs.

Everyone rides at your FTP

Set it on the start card. The bunch is as strong as you, so a turn on the front is about 120% of your FTP and sitting in is about 80%. An hour on it is a proper session.

Real gears or a single speed

Tell it what your turbo bike is in and it works the resistance out from there.

The road is real

Rufforth, Long Marston, Cowthorpe, Wetherby, Wighill, Askham Richard: the villages, the junctions, the hedges and the fields, with the crops in them from the national crop map.

A Strava file at the end

Power, cadence, heart rate, speed and the route, as a Virtual Ride. Plus pictures to post with it.

Free, and no account

Chainy sends no ride data anywhere. Your settings stay in your browser.

How it works

Get on the turbo. Open Chainy in Chrome or Edge on a laptop, PC, Mac or Android. Turn the trainer on.
Put your FTP in and press Start the Chainy. The browser asks which trainer to connect to. Pick yours. A heart-rate strap is optional.
Start pedalling. The bunch rolls out from standing with you, about 30 seconds to pace.
Hold the wheel. The number on the back of the rider ahead is the gap to your front tyre. Keep it small.
Do your turn. When you reach the front you're the pace. When you've had enough, ease off and you pull over into the recovering line. The rider who comes past flashes red: that's your cue to go across onto their wheel.
Finish over the line and download the Strava file.

Questions

What do I need?

A smart trainer with Bluetooth. We've built and tested Chainy on a Saris H3. Other trainers that use the standard FTMS Bluetooth protocol should work too, and that's most of the last few years' models: a Wahoo Kickr, a Tacx Neo or Flux, an Elite Suito or Direto, a Zwift Hub, for example. If yours doesn't, tell us through the feedback form and we'll look into it. A heart-rate strap if you want heart rate in the file. And Chrome or Edge.

Will it run on my phone or tablet?

Android: we expect so. Chrome on Android can connect to the trainer and the screen lays out for a phone, but we haven't ridden it on a real one yet. iPhone and iPad, no: Safari can't do Bluetooth, so the trainer can't connect. You can watch the Simulator ride it, but you can't ride it yourself. We'd rather tell you now than after you've set the bike up.

Which browsers?

Chrome and Edge on Windows, Mac, Linux and Android. Firefox and Safari don't do Web Bluetooth, so no trainer.

Does it need a fast computer?

It picks a graphics level on the first load and drops down if your machine is struggling. We expect a laptop from the last five or six years to be fine. If it's choppy, press Q or the Quality button to go down a level, close other tabs and plug the laptop in.

What does my FTP do?

Everything. The seven others ride at your FTP, so the front rider's turn is about 120% of it, the line about 80%, and the whole ride is possible. Set it honestly. Set it high and you'll be dropped; set it low and you'll be bored.

How does the gearing work?

Tell it the chainring and sprocket your bike is actually in. "Auto gears" then changes the resistance for you so you spin at a cadence you pick; "Real gears" leaves it to your legs and your shifters. A single speed works fine.

The bunch waits and I'm pedalling. Why?

It's not seeing power or cadence from the trainer. Check the trainer's light, that nothing else is connected to it (a phone app, a head unit), and that the browser asked to connect. Reload and connect again.

Can I ride with a mate?

Not yet. It's you and seven riders made by the app.

What happens to my ride?

It stays in your browser. Chainy stores no account, sends no ride data anywhere, and the Strava file is made on your machine and handed to you as a download. Upload it to Strava yourself.

Where's the road?

The Clifton chaingang loop, from Clifton in York out through Rufforth, Long Marston and Cowthorpe to Wetherby and back through Wighill and Askham Richard. Heights and roadside from the Environment Agency's laser survey, the fields from the Rural Payments Agency's crop map, the roads from OpenStreetMap.

Found a bug?

Broken page, or got an idea? Tell us. We fix mistakes in the open.

Credits

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