@Neil_Mager , We just added a treadmill (she’s an ultrarunner.) No room for a 2nd bike!
I did my first Zwift run today, then I did a Zwift 5K, which is the first time I have ran more than 1/2mi since 2016 (coming back from a kidney transplant – most of my exercise is on a bike.)
Hi All,
Please bear with me as this is a bit of a long post but completely relevant to this thread…
I’m really glad that I found this thread as I just started on Zwift a month ago. I’m not a cyclist (at all), and I’m using a Bowflex C6 and having tons of fun paired with Zwift. I have Crohn’s Disease and only Zwift 2-3 times a week for cardio as I don’t need to be burning tons of calories. I’m in really great shape otherwise, but was a little surprised by how well I was doing on Zwift. However, I didn’t think much of it as I’m not in it to compete with others, I usually just ride by myself and pedal as hard as I can for an hour, until I did one of the Tour de France Discovery Stage group rides the other day…
I had registered for the A group using the metric that Zwift had given me for my w/kg, not knowing that this was severely skewed where it’s just a virtual number they calculate. At the beginning of the ride a couple of others that were in the group started talking about zpower and people cheating using trainers. I wasn’t sure but had a bit of feeling that they might have been referring to me as I was out front so I politely asked who they were talking about and what was zpower. Another person in the group politely replied and said to google it and I asked a legit question on my behalf: “If I’m using a Bowflex C6 and my w/kg is anywhere between 5-6w/kg, is that not an accurate assessment of my power rating?” The guy replied that it wasn’t unless I was an elite athlete. As I said, I’m in really good shape, but definitely not an elite athlete, hahaha.
I think this is a bit of a problem for a couple of reasons, the first being that it seems to generate a bit of angst among some “real” cyclists who feel like they’re being cheated by people using spin bikes/trainers that over-exaggerate power ratings - I’m sure there are others in the same boat as me and have no idea that this is the case, and that the power rating that Zwift gives you using the C6/IC4 is only a virtual number. The virtual power rating given to me by Zwift is so far off what the actual number seems to be is a little crazy. Thanks to Matt Larson for posting the image with the calibration process. The C6 connected with Zwift so easily when I did my first ride that I had no idea anything was off in terms of power rating and other metrics. I followed the calibration process that Matt posted and I think it worked as my average w/kg is now anywhere from 2-3.5 w/kg when riding. I’m still passing some people, but I’m not winning any jerseys anymore, lol.
This doesn’t seem to be an issue with Zwift at all. I’m no expert, but is it not possible for Schwinn or Bowflex to have the computer properly calibrated when it leaves the factory so it’s set up properly for use by consumers to give a sane measurement of power, speed, etc? If the bike is not calibrated properly then it makes sense that Zwift will give you an insanely high power rating and all other metrics will be off. If it is calibrated properly then the power rating seems to be more realistic. As I said, I’m not a cyclist and have no idea about power ratings and what not, and obviously using a power meter is the best way to get a true number. Maybe Zwift or Bowflex could give people a heads up that this is the case and avoid some of these issues. I didn’t read anywhere in the Bowflex manual about calibrating the C6 after assembling it, and in reading some of the info about “your first ride on Zwift” I did not see this issue come up at all.
One quick question about the calibration process: after I calibrated the the C6 I found that cranking the resistance up to level 20 was super hard, would that make sense? I had been setting the resistance between level 40-50 in most cases prior to calibrating, and it was nowhere near the resistance that I’m now getting, even at level 15. As someone else said above only being to calibrate the computer/bike 3 times does seem a little crazy, could this be fixed with a software update? If I did the calibration process incorrectly and had to do it again then I would be on what the computer says is the third calibration process. Any info on this would be greatly appreciated. Cheers!
I have 2 IC4 bikes that my wife and I work out on. They both needed calibration of the magnet out of the box. What tipped us off was that resistance could be at 100 and we could still pedal slowly until we turned the knob 3-4 more times. After calibration, we come to a stop 1 turn after 100. Numbers much more in line with expected watts, and we’re not flying by everyone easily. Will probably eventually get pedal power meters for both bikes, or at least one to verify that the virtual numbers are close to the actual watts, but for now, it’ll do. We’re not super competitive and just trying to get a good workout despite COVID, but don’t want to be cheating anyone either. I think we should get the word out that most of these spin bikes need to be calibrated before using Zwift, if shelling out an extra $500 for a power meter isn’t an option.
I think the Tempo Power Meter solution highlighted above looks promising. I checked out the prices on their website and they are around $200, which is very reasonable as power meters go. I don’t think you can get any pedal power meters for that price, correct me if I am wrong.
I just think it is worth waiting if they are going to have an ANT+ & Bluetooth solution, so I can run Zwift off my laptop.
Other issue is the cost of the crank: it seems crazy having to pay $60 for a crank on eBay (even if flat taper square and 25mm)… there’s got to be a cheaper way to get a crank… those that come on the IC4 look really cheap.
Hi Brad, did you ever manage to find or create some IC6 meetup groups, would love to get involved!
Same situation here, power numbers seemed way too high. So i actually did buy the Garmin Vector 3s pedal power meter. Very rough FTP estimate is now about 100W lower than before. Feels a bit low, but probably the truth.
I could post some comparison numbers, but would like to know the crank length of the IC4 (IC8) first, as it is an input for the pedal power meter. I measure it around 172mm.
Also, I have not calibrated the IC8 yet (it felt somewhat too early with no reference and only 3 tries)… but now I could do it… or pair up for a ride for comparisons…
For what it’s worth, with the new IC4 I got about a month ago, it’s completely out of the box with no recalibration. 3 days ago, I averaged 114w over 15 miles in Zwift according to Strava (but apparently I’m too new to embed the screenshots as evidence).
My most recent outdoor ride today (estimated by Strava because I don’t have a power meter) averaged 89w over 16 miles in Strava.
Accurate enough for my needs (but I’m just getting back into biking more regularly again, so I admit the resistance levels are in the 0-30 range most of the time). Hopefully that relative accuracy keeps up as I build strength.
The difference between 89w and 114w is pretty significant—a factor of 1.28. If I were riding around at 300w and then applied the same factor increase, I’d be at 384w (easily the difference between merely participating in cat A races and winning them outright).
Good point, except it’s also not quite apples-to-apples and I should have pointed that out. I live in a major city, so the outdoor bike ride had a lot more stopping and starting for traffic lights.
I just received my ic4, the resistance is crazy hard out of the box, over 50 is barely doable. Also the speed on bike does not match the speed on swift. Should I return the bike or work on it ?
Thanks
The speed on the Spinning bike won’t match Zwift. The spinning bike does not know if you are going up or down in Zwift. Ignore the speed on the spinning bike.
I assume the resistance will be hard at the higher levels.
thank you
Got my IC4 a couple months ago but just starting on Zwift. Power readings do seem high (20-25%?) so will have to try the recalibration. Any IC4/C6 groups/rides info appreciated.
Curious about the groups as well. When you do the calibration, watch the 100 end. I set it way too high and had to recalibrate, so I’m at the magic 3 and now I fear I’m on the high end still. I wish I saw the speed test post before I did the calibration. I’m going to try that tomorrow and see where I am.
50rpm at 0 should be 5mph and 75rpm at 25 should be 23. Now I don’t know if that is just on the IC4 monitor or if that is in the game at Zero incline. I’ll try it and see what I get.
Hi, newbie here, Just set up the Bowflex C6 yesterday, and did the short FTP test, and did a GCN tempo training ride today. I am a decently strong rider for a 50 something, but I also think my test result is overrated a bit. Will keep learning and see if I can do a calibration. I am also looking into installing a used Stages power meter crank as a possible solution.
This bike will work for our family, and if I can use it to get some good training in, with reasonably accurate feedback, that is good for me. I don’t have the dough for a super spendy smart trainer. Thinking with some tweaks, this should work out.
Also interested in connecting with other Bowflex C6 and Schwinn IC4 riders for training, social, group rides?, fun races? Cheers! Steve
Hey Mike,
Did you ever see if you got the calibration to line up with the speeds? I just re-calibrated mine twice now and they aren’t lining up. The 50 RPM at 0 is at 13 KPH for me (should be 9) and the 75 rpm at 25 is at 31 KPH for me (should be 37). I have now calibrated twice so have to call Schwinn/Nautilus for a new meter I guess. Really frustrated. Was just wondering if you got yours to work? This test I did with the power meter on the bike, not Zwift.
I have never really biked before and I am slightly injured but an ex college athlete that is 28 so I’m not in terrible shape. I couldn’t even hold 130W for more than a minute without dying so something definitely isn’t right…
Hey Andrew,
I recalibrated just the same as you did and get those same numbers (13kph at 50 etc) I really think this is something that we should be contacting Schwinn about and asking for a firmware update, I have to imagine this is solvable via an update to the console if our numbers match after calibration
Patrick,
That’s extremely interesting that we have the same values after calibrating. I talked to Nautilius/Schwinn last week and they are currently sending me a new power meter. It’ll take about 3 weeks to ship. I also asked for someone to come over and install it in hopes of learning more about this and if something doesn’t go right I can actually talk to someone about it immediately that is considered an “expert”. I’ll make sure to update on my results when the time comes
Those spin bikes do not have a real power meter so they will never be accurate no matter how many times you replace them.