calibration ride

[sjeffrey]

Hi,
just recently got my PowerPod and excited to use it. What had me decide on this product is because I want the ability to switch bikes easily.
More often I will be using a hybrid bike with a trailer and 1-2 kids riding with me. I set the my weight and add bike, trailer, kids, etc. to the profile and plan to adjust according to who is riding with me. I've been out 3 times now and particularly one ride had many instances of 0 watts. When I get numbers the power seems slightly high.

I attached the particularly bad ride. The wind was pretty nasty so maybe that explains the 0 watts. Around a quarter way in the ride I had lots of tail wind and rain which prompted me to cut the ride short and turn around which is then obvious how windy it was during the second half. I checked to make sure that: the mount was solid and cadence was not dropping out.

I would appreciate a quick review to see if there's something I can tweak.
I also attached the calibration ride that was done. You can see after 8 minutes my power output was way too high. Assuming I did everything correctly that ride was setup with the weight of only myself and the bike, no trailer or kids on that ride.

Thanks

[sjeffrey]

Ok well I've been trying all week to get this thing to work with little success.
Today however, I was able to take my road bike, on my own, and do a calibration + a 30km ride.
The graphs look much better to me but I think the power numbers are little high. My average watts was 230w which would be great but my last FTP test on Kickr was 207w.

I will more likely be pulling a trailer when I get to go for a ride so I would really appreciate getting some help dialing in the numbers correctly for that setup.
Assuming this profile is correct, would it be just a matter of correcting the total weight to get the right numbers?

I attached the calibration and 30km ride.
Thanks

[Velocomp]

Your rolling resistance is high.

Load this into your PP and you should get good results.

[sjeffrey]

Thanks for the reply John. That brought down the avg watts to 149w which is probably much closer to reality.
For riding with different bike with a trailer, any tips on getting proper calibration? Is the friction value what should be most different? I played with total weight and that doesn't seem to affect power that much.

Thanks again John, I really want to make best of use of this product and getting it dialed in properly is key.
Stephane

[Velocomp]

I'm not sure what you mean by a "bike with a trailer".

Please post a photo...

[sjeffrey]

Since I have 3 young children most of my rides consist of a hybrid/MTB pulling a child carrier. I attached a photo.
I saw your reply to a comment about pulling a trailer that you posted on DCRainmaker's review page about simply adding the weight off everything and Powerpod will take care of the rest. That comment is what prompted me to purchase the Powerpod. I figured I could calibrate it for the bike with the kids and when I can ride alone, simply swap profiles and mount on my road bike.
My concern is that surely adding the carrier will affect friction, rolling resistance, etc. That's why I ask how should I go about getting the right calibration for this setup?

Stephane

EDIT: Upload got blocked, added a smaller version.

[Velocomp]

The primary thing you'll want to get right is the total weight of your bike + all extras; including weight of trailer and kids!

Rolling resistance will be affected some, due to the two extra tires. But I don't think it will be a huge effect. Your 4/10 ride file has a rolling resistance equivalent to riding in soft sand!

CdA will increase some also

Note that, if you're riding on mostly level surfaces, weight won't be a huge factor except when you are accelerating.

Please do the following:

1) post a solo ride file, without trailer and kids

2) Post a trailer ride file, where you pedal with approximately the same level of effort.

We will use those two ride files to adjust things

[sjeffrey]

Here's the 2 files. It was the same ride with the first portion alone on bike without anything attached. 2nd is with trailer and kids.
I believe it was set to the profile of my road bike and numbers actually seem pretty close to me.
The weight of me and bike is about 92kg. With trailer and kids, 142kg.
Hopefully those 2 files will help. If you need an O&B of each I can do that later on the weekend.
The mounting position have a big effect on things? This bike is a hybrid with MTB style handlebars so I put hands on hoods as I guess it's the closest match.

Thanks again for the help!

[sjeffrey]

Bump please

[Velocomp]

Sorry for missing your earlier post...sometimes they don't show up as unanswered.

Your wind calibration is pretty far off. Because these are not an out-and-back rides I am reluctant to change things.

Please do a solo O&B ride and post the result.

If you want to know how to do an O&B ride, we've just posted a video. You'll find it elsewhere on our site.