I hate you Zwift! (But I love you more…)
Like some other Zwifters I have a mild self-diagnosed OCD which among other things makes me get up at 4am every Friday for my BoOCD2000 ride which is my own route including the Radio Tower, Alpe, and a u-turn on the way down the Alpe to hit precisely 2000m.
And the reason I hate Zwift (well not really but…) is they choose to roll out a new (buggy) update almost every single Friday which isn’t really what you want to see early in the morning when trying to ride before work.
A few Fridays ago, the story repeated, and a new update was forced on my Win10 setup. Fortunately, I’m on a quick connection and decent hardware so when they roll out an update it downloads quickly. I got the update and started riding. Went on the forum while getting some heat in the legs, just to see how many bugs people already has discovered, and discovered that the new steering feature had dropped like a bomb.
First thought was “Nah… don’t really want steering, I’m here for the pain.” And a few hours later the order confirmation from the Zwift store hit my mailbox. 😊 (Of course… guessing that the Sterzo units probably would be sold out very quick I couldn’t resist ordering one, just in case I would change my mind about that pain thing.)
The package from Zwift arrived very fast (Tuesday) here in Denmark and installing the Sterzo on my old Neo trainer setup was a 5-minute job. The Stages SB20 next to it looked a little sad when it realized that it was “outrun” by a well-used Neo and an old Trek fitness FX bike.
The first test was quite impressive, and a few rides on the Repack Ridge MTB course was a lot of fun. Especially if you ignore that I got slightly seasick!
Finding the Line
The next Friday after some outdoor riding and zwifting on the Stages bike I decided to jump on the Neo for my Friday BoOCD2000 and just activated the steering because I could. A few miles into the ride an idea popped up: why not try to steer on the optimal line up the Alpe?
So while trying to figure out if it was a great idea to climb 2000m fasted early in the morning I was also trying to estimate if actively steering for the optimum line would make any difference. But I didn’t really come to any conclusion, so I kept climbing.
No steering Steering, optimal line
At the top (well more like on the way down when trying to find some oxygen) comparing the photos from a non-steering BoOCD2000 ride with the active ride I realized that I actually rode 600 meters less during the 40km ride by actively keeping the optimum line!
Bad, On Purpose
Of course, my mind had to mess with me, so for the next Friday morning ride there wasn’t really anything to do but try riding the same route while taking the worst line and see what distance that would result in on the top.
For some weird reason Zwift didn’t have an update ready that morning and I just hopped on. The legs weren’t quite as enthusiastic as I was, but at the top, the distance ridden was 500 meters longer than the non-steering ride – making the difference between the optimum line and the worst line 1100 meters!
Conclusion
The distances stated above are from the photos included in this article. There might be a slight difference where they are shot, but Garmin connect shows the following distances to the same point at the top of the Alp which confirms everything:
- Normal no steering: 40.79 km
- Steering optimum line: 40.25 km
- Steering worst line: 41.90 km
For me, the surprising conclusion is that line choice does affect the distance ridden. Well done Zwift! 1100 meters less on a 40km ride is quite a lot if you are racing.
This isn’t a scientific test, just me having fun trying, so you might want to do a few tests of your own. It’s fun and you get to be on Zwift so why not? Ride on!
Questions or Comments?
Share below!
This is a really interesting article. As a non-zwift user (but planning a set up for winter) I’m intrigued if there is a gradient change from the ‘worst’ to the ‘best’ line(inside to outside of corner) , as on a real mountain you might take the longer, less steep route round the outside of the bend. Does Zwift account for this?
Yes https://youtu.be/84HJCkpvtQs
Thanks for posting this. This is really interesting and positively surprising.
Unlike a flat TT, I wonder if taking the perfect climbing line is more sapping or takes longer as you are on the steepest albeit shortest route. Therefore a heavier rider could not spin as efficiently and gather as much speed or have mini-rests. Maybe it’s not enough to make any difference.
Climbing same amount of vertical meters but on steeper grades will actually be faster (take less time) at the same power.
Not in the real world. But I doubt Zwift is modeled that precisely.
There are 3 components to energy used in the standard model: wind resistance, rolling resistance, and potential energy. The potential energy depends only on the altitude gained. Wind resistance and rolling resistance depend on distance. Just considering rolling resistance — it adds 0.3% to the effective grade, typically, on Zwift. So for L’Alpe, that’s approximately 3.5% of the total (8,5% grade). So cutting 1% off the distance w/ steering would reduce energy required by approximately 0.035% off the energy required. Time = energy / power so this is around 1 second saved in a 50 minute climb.
Same question for me, does the line you take make a difference to the gradient?
yes- see above youtube link to a guy testing that
Based on the final screenshot, I think this should say 40.90 km
And this should say 100 metres (the difference between 40.90 and 40.79 km)
And this should say 650 metres (the difference between 40.90 and 40.25 km)
Hi Oliver. Please notice the numbers you are referring to are the numbers from Garmin. The reference point for these numbers differs from the reference point for the screenshots. The screenshots are all done just after passing the banner. The Garmin numbers at the point where the loop on the top joins ( me trying to place the cursor at the same point… )
The distances using the screenshots is 39,8-40,4-40,9 using the Garmin with another reference point 40,25-40,79-41,90. Not exactly the same variation between the three but still significant numbers no matter what method I’m using.
Wow! I wouldn’t have expected such a huge difference. Were you steering throughout the entire ride or just up the Alpe? I figure it was the entire ride, but that difference sounds enormous.
The “Bad Steering” distance should be 40.9 km, not 41.9, according to your screenshot. That would present a significant difference.
Hi Renzo. Please take a look at my reply to Oliver 😊
Has anyone tried the sterzo smart on la reine or Ven top yet
What difference will having steering make on these routes
La Reine and Ven-top are much straighter routes with very few turns. Steering only saves distance when turning, so you wouldn’t see as much of a benefit.
Hi Daz Ellis. I might give the Ven Top a similar test at some point. Please notice the distance in this article also includes the Epic KOM and Radio TWR which makes it 3 times as long as the Zwift Ven-Top route, and probably also a higher percentage of turns vs. distance.
Nice article Boo, enjoyed it!
Thanks Mike 😀
Useful information for a vEverest of the AdZ… I’m reading stuff to prepare a vE. First I want to buy a new bike and than a Sterzo Smart. Less kilometers and same altitudegain + gradients will be a nice thing 😲
A standard lane width is 3.7 meters. So assume a difference of 3 meters taking an inside versus outside line within a lane (need room for the width of the rider). You saved approximately 900 meters taking the inside versus the outside line. This suggests 300 radians of cornering. That is approximately 48 complete circles, or 1.2 circles per km traveled, or for example a right-angle turn every 210 meters. Of course switchbacks are closer to 2 right-angle turns. So it seems in the range of plausible.
Correction: 1100 meters (not 900 meters) saved. So that’s 370 radians total, or one right-angle turn every 175 meters. Of course it may be moving laterally more than 300 meters, as well, for example using the shoulder, or overlapping the center line.
nice fan set-up in your pain cave!
Thanks Sven 🙂 It works pretty good combined with a large fan in the ceiling 😀
Now all the race cheaters are definitely going to buy a Sterzo since we know they will do anything to win a race.
pretty dumb comment
Except Steering is off automatically for all races (unless its a steering race or organisers allow it). It’s also hardly cheating, you can get a cleaner line, but you’ll pay for it by eating air…
Great article Bo! I’m new to Zwift (using a Peloton bike with speed/cadence sensors for now) and trying to decide on a full smart bike (like the Stages SB20) or get a used bike and attach to a smart trainer. Now that steering is an option, does that make many of these smart bikes a bit limited? I think I read the Stages bike has additional buttons that could possibly control steering, but not sure if/when that will be implemented. Do you prefer the Stages bike for Zwift, or do you prefer a real bike with a smart trainer so… Read more »
Thanks Jeff 🙂 Since steering is pretty low on my priority list I wouldn’t let it influence my choice of trainer bike that much – if at all… I can talk and write for ages about the pro and cons of the SB20 compared to my traditional setup, and I might do an article on it at some point. But the short version is.: If you like getting “in the zone” pushing constant high watts – especially on climbs – the experience on the SB20 is amazing and very smooth. If you are more into getting close to what you… Read more »
Thanks for the reply Bo, much appreciated. I’m leaning towards the SB20 since I like the idea of an all-in-one smart bike… now the big question is how do I tell my wife I want to sell the Peloton?!! 😁
You either don’t tell or just keep the Peloton AND buy the SB20 😉😄 You will love the SB20 🙂
This sends tingles straight down to my bike pedals Boo😉. Thank you for thinking outside the box and putting your thoughts🤔 to the ultimate test. Your mild OCD must have been on overload (which I can fully appreciate 😁) while you where analyzing the data. I look forward to testing this and having fun with it myself some day, but I will have to wait until my Kickr Bike buttons will be enabled to do so. Thank you for taking the time to share such a fun, interesting, and engaging topic. I look forward to your future posts and perhaps… Read more »
Hi Kris 🙂 Thanks and glad you like it. As you probably already discovered I have been collecting data for some more writing. let’s see if something shows up ? 😉 Looking forward to meet you somewhere in that orange world 🙂