PowerPod w/ ElliptiGo long-stride bike

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marksibert
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Joined: Thu Jul 30, 2020 3:24 pm

PowerPod w/ ElliptiGo long-stride bike

Post by marksibert »

I'm thinking about getting the PowerPod for my ElliptiGo bike. Wondering if there is anyone out there that is currently using one, and if there are any considerations/challenges to keep in mind when setting it up, calibrating it, etc.

I've never used a power meter on a bike before. (I never rode much before I got the ElliptiGo.) So I'm really curious about the calibration aspect, and how to know if the data is reasonably accurate. I don't expect it to be perfect -- just something that's in the ballpark.

Thanks!
Velocomp
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Re: PowerPod w/ ElliptiGo long-stride bike

Post by Velocomp »

We tried our power meter with an ElliptiGo some years ago, and it worked!

If you decide to get a PowerPod let me know and I will help you set it up on your ElliptiGo.
John Hamann
trailrunner
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Location: The Netherlands

Re: PowerPod w/ ElliptiGo long-stride bike

Post by trailrunner »

Hello,

I'm a Elliptigo 11R-rider and just bought the Powerpod V3. I'd like to use it on my elliptigo. My tiresize is 20x1.50 Schwalbe Marathon, as a bikecomputer I'm using Garmin 6x Pro. Do you have a setup for the Powerpod?

Kind regards Carl
LosAltos
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Joined: Fri Feb 10, 2023 9:27 pm

Re: PowerPod w/ ElliptiGo long-stride bike

Post by LosAltos »

John,
I also want to buy a PowerPod for my Elliptigo. How do I get the instructions you mentioned to set it up? Thanks.
Dan
Velocomp
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Re: PowerPod w/ ElliptiGo long-stride bike

Post by Velocomp »

LosAltos wrote: Mon Feb 13, 2023 11:37 pm John,
I also want to buy a PowerPod for my Elliptigo. How do I get the instructions you mentioned to set it up? Thanks.
Dan
Follow the same instructions that work with a standard bike, but make sure you enter the correct wheel circumference for your Elliptigo. Also, make sure you attach PP so that it can't rotate on your handlebars.

You can do a standard cal ride with your Elliptigo. Post a ride file afterwards and I will look at it. The CdA will need to be adjusted upwards, to account for the upright position you have when pedaling.
John Hamann
markw65
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Joined: Sat Jun 10, 2023 11:11 am

Re: PowerPod w/ ElliptiGo long-stride bike

Post by markw65 »

I've also just started using a PowerPod v5 with an Elliptigo. Would appreciate any help configuring it.

I initially tried setting it up through Isaac, giving the correct wheel circumference as suggested. The results were clearly off, but at the time I was on vacation, and only had a Mac, and although I could use it to configure the Powerpod, the rides wouldn't download. Also, while searching the forums for a fix, I deleted those rides (before finding that this is expected behavior on MacOS Ventura).

The next thing I tried was to increase Cda from 3.75 to 4, and recalibrate. Then I did a ride with a long hill, and (just looking at power vs heartrate) things looked a lot better, but it seemed like power was too low on flat to gentle up hills (relative to steep uphill, since I have no idea what my actual power output is). I tried increasing crr since I use Schwalbe Marathon Plus tires, which I believe have pretty high rolling resistance. I was going to repeat the previous ride, but I've had a cold the last few days and didn't feel up to it, so I've just got a gently rolling 5 miler with that profile.

I'm now back home, with a windows desktop, and able to download the rides into isaac. Looking at the longer ride, it thinks I was braking all the way down the hill. In fact, apart from a stop due to roadworks, I'm pretty sure I hardly touched the brakes (its a really nice descent, with long sweeping curves and a mostly good surface), and was actively pedaling some of it. I assume that increasing crr (as I did for the second ride) would help with that; but I also suspect that Cda is still too low? [edit: I tried using "Check Calibration" on it, and by changing to "Touring" tires at 80psi, some of the downhill changed to coasting, but most was still braking; then I increased Cda gradually, and at .65 all the braking was gone. Is this a reasonable way to tweak things?]

I should add that I'm already pretty happy with it, but the perfectionist in me wants to get the best possible results. So any help would be appreciated!

Thanks
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Velocomp
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Re: PowerPod w/ ElliptiGo long-stride bike

Post by Velocomp »

You have good intuition!

When coasting down a hill, CdA will be correct when the "braking" disappears.

In your case, applying a CdA of 0.65 to your profile 1, and applying this profile to your "profile 2" ride, results in everything looking great.

Load the attached profile into your unit, then you should get great results!
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John Hamann
markw65
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Re: PowerPod w/ ElliptiGo long-stride bike

Post by markw65 »

Great, thanks!

After sending that profile to the device, should I do a new calibration ride? Or is it good to go?
Velocomp
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Re: PowerPod w/ ElliptiGo long-stride bike

Post by Velocomp »

markw65 wrote: Sun Jun 18, 2023 8:20 pm Great, thanks!

After sending that profile to the device, should I do a new calibration ride? Or is it good to go?
You're good to go; no need to recalibrate.

I think it is really neat that you're getting power numbers from your Elliptigo. You might want to tell Elliptigo about how you are using PP as a power meter for the bike. It is a very novel solution!

In the mean time, post a photo showing your bike set up with PP :-)
John Hamann
markw65
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Joined: Sat Jun 10, 2023 11:11 am

Re: PowerPod w/ ElliptiGo long-stride bike

Post by markw65 »

I will definitely post my findings in the Facebook elliptigo group once I feel like I've got things setup well.

I've done another ride. I did tweak your profile slightly, increasing Crr to .0081, because that's what Isaac tells me for touring tires, 80psi, 20" diameter.

Things mostly look good (to me).
- Power always went to zero when I coasted, even when going fast down hill (I think that means that CdA isn't *much* too high)
- Wind speed seems reasonable (I started out mostly into the wind, and finished mostly with it behind me, and the isaac graphs agree)
- There's a rough correspondence between power and heartrate for most of the ride (but see below).
- The descent from the high point on the route is steep and winding; I really was braking most of the way down, agreeing with Isaac.

The problems I noticed are
- Around 10 miles, I tried pedaling hard as I was getting to the bottom of a hill I had coasted down; suddenly power was over 1000W. I was definitely pedaling harder *up* the hill when it was showing 200-250W. The same happened on a couple of later hills.
- between about 17 and 18.5 miles, it was mostly flat with a following wind. If I did any significant pedaling, power easily went up to over 600W. Here's a picture, power is vertical, hr is color.
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Out was right to left, into a head wind (with power mostly between 150 and 250, and relatively high heart rate), and back was left to right with a following wind. But the sections where I pedaled on the return show huge surges of power (~600), with low heartrate.

I think both of these point to CdA being too high - but the fact that coasting always returned power to zero suggests (to me) that its probably not *much* too high.

Any suggestions?

[edit: Answering my own question: I went back to the 31 mile ride where I had concluded I needed to bump CdA up to 6.5 on the basis of a long descent that I had coasted down. But as I said in my original post, I *did* have to come to a complete halt part way down due to road works. And all the braking *except* for that short section goes away with a CdA of around 5.75. So changing it to 5.75 works well for that ride; and it also works very well for this one. We'll see what happens tomorrow, but I think 5.75 is looking good]
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Velocomp
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Re: PowerPod w/ ElliptiGo long-stride bike

Post by Velocomp »

On an Elliptigo you stand up pretty straight, which means that CdA is higher.

If CdA is too high then you'll see high watts when traveling at high speeds.

I looked at your ride file with a CdA of .575; that does seem to fix the few outlier spots.

Let me know how your next ride proceeds.

PS: I used to live in the Santa Cruz mountains, just off of Summit Road in Los Gatos. You have a great area for cycling!
John Hamann
markw65
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Re: PowerPod w/ ElliptiGo long-stride bike

Post by markw65 »

On yesterday's ride I noticed I could still get some very high readings when pedaling down hill (although only 3-400W, rather than over 1000W), so I've dropped the CdA to 5.55. Today's ride looked fine, but was easy and flat. The next serious ride with hills will be Saturday. But I'm pretty confident that I'm homing in on the right values.

Anyway, thanks for all the help. You asked for pictures, so:
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Velocomp
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Re: PowerPod w/ ElliptiGo long-stride bike

Post by Velocomp »

I like it! Tell Elliptigo that you are using a power meter on their bike...and which one :-)
John Hamann
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