Could I, in theory take the pedals off a stationary bike at a gym, put my power meter pedals on, and do a TR workout? I assume that seeing the gym bike isn’t connected to TR I would have to run the workout through my Garmin?
Also, I’m guessing you measure crank length from centre to centre?
Thanks in advance
You wouldn’t be the first TR user to do this, so it’s not completely crazy. You can run the power pedals to the mobile app, no need for a Garmin.
Thanks mate
Yes, center of the holes is the functional length and what matters for power calculation.
Additionally, many/most cranks will have their length listed on the inside surface of the crank arm, usually around the threaded pedal hole.
ETA: Here is the TR blog on training during travel that includes this scenario and others:
I’ve done it before without power, with my phone sticky taped to the screen, and just using RPE and ramping up the resistance for the intervals.
It was still a proper workout (even though it was not scientifically accurate on power). The lack of the usual hurricane force cooling fans meant that I ended up looking like someone had thrown a bucket of water over me and I got a lot of strange looks from the other users who were just pottling along at 50W.
Great fun. I’ll do it again when i’m next travelling for business.
If I’m traveling, I’ll bring my HR strap and just do the workout according to RPE and heart rate. Way less of a hassle than bringing pedals and wrench.
And given a choice, I’ll select workouts that are simpler, i.e. longer sustained efforts at the same wattage or Vo2 work that is more on/off.
Yes, you can. I brought my favero pedals, hr strap and a trainer with me to my parents’ home while visiting for Thanksgiving - banged out an hour of sweet spot on an old bike and got’er done. Used my ipad to load the workout.
Yes, I’ve done it
If you can check what tools you need for the gym bike pedals first it will save disappointment or taking a tool box
They can be rusted on so a little grease too
Perfect. Thanks.
Bugger. I should have checked last time I was there. Assumed it was just an Allen wrench.
I’m pretty sure, @Nate_Pearson has done this in the past. I remember him talking about it several times, including how to evade suspicious eyes when you bring tools with you and start wrenching on gym equipment.
I’m trying to picture Nate attempting to be inconspicuous in a public place. 
Not easy, being 6’ 13” and all 
I’ve done this when I used to work construction and stayed in a camp. Camp had a gym with spin bikes so I took a pedal wrench, my vector 3 pedals and heart rate strap. I also used a quad lock case and mount that used rubber band to connect phone to bars and run TR mobile app. Worked great but one issue I ran into was the limited fans in the place so ended up bringing my own small lasso 4900 as well.
Do you do the workout in the mobile app (so heart rate is recorded) or treat it as an outside RPE ride?
Someone made an open-source piece of hardware to do exactly the same thing and essentially make it a smart bike. Works great with TrainerRoad. I use one on my peloton. Does still require power meter pedals for most bikes.
I’m currently doing all my TR workouts on the spin bikes in my condo gym due to a lack of space in my place. It’s a minor inconvenience to get set up each time, but overall hasn’t been too bad. I bring down a musette bag with pedals, pedal wrench and a tablet and/or phone to run TR and watch something as well as a Lasko style fan which is small and has a handle for carrying. I keep the stock pedals on the bike well greased so it’s easy to swap them each time - that would be less of a possibility on a hotel bike but since I’m always using the same bike it’s easy enough. I was grumbling about it when I found it would be my only option for the foreseeable future but it honestly hasn’t been too bad.
I’ve been in the gym and paired Stages SC3 stationary bike with TR app, Zwift app, RGT app, Garmin 530, and a sometimes two at the same time: TR/530 and TR/Zwift and … (iPhone using the old Wahoo ANT+ dongle).
The Stages bike has a flywheel with some weight, but without electronic braking the only weird thing is that the bike is like a fixie and after say a 30-second sprint I’ll try to briefly freewheel like outside or on the trainer, but the flywheel will keep the crank and pedals spinning like crazy and force my legs to keep moving
I use the mobile app and record my heart rate — the first option.
Every week. Just use rpe and run them as outdoor workouts. I fly frequently for work and lugging power pedals and a wrench just isn’t practical for me.