iBike import to Strava not grouping with other riders

rstrom
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iBike import to Strava not grouping with other riders

Post by rstrom »

Hello,

I've been importing iBike ride files (after merging the FIT file from a Garmin 500) to Strava for close to a year now and the only issue with group rides not matching up with other riders was last fall when there was a switch from daylight savings time to standard time (the iBike used PST local time, not UTC/Zulu and there was an issue with that - FYI - I am in Arizona and there is no DST. That is the reason that there was an issue when changing back from DST to standard time. This was fixed pretty quickly by the iBike folks by exporting GMT time to the CSV file).

For some reason the issue has sprung up again starting this past weekend.

On Saturday I rode with 6 other riders that were using GPS/posting to Strava and the uploading of the iBike file matched none of these riders. As a test I uploaded the Garmin file and it did match all of those riders.

On Sunday I rode with another rider and when I uploaded my iBike file Strava failed to group the two of us together but when I uploaded the Garmin file we were grouped together.

Here is the original ride file posted using the iBike CSV

http://app.strava.com/activities/52579384 (no rider groupings)

Here is the one uploaded using the Garmin file

http://app.strava.com/activities/52355560 (rider groupings)

I have submitted a ticket to the folks at Strava and they are looking into it but I wanted to throw it out here to see if anyone else has experienced this or knows what it might be.

The Strava support person has said this so far.

Mat Gordon, May 05 02:58 pm (PDT):
Hello-

That's a good question. I'm actually not sure what's causing the iBike version to not be grouped appropriately. It's got the same start time and all the same segments - which is the important thing. Unfortunately I don't really have any insight into the matching process other than the fact that when I prompted it to re-check for group activities, it didn't find any.

I'll see what I can dig up, but in the meantime at least the Garmin version grouped properly.

Sorry for the trouble.

Mat
strava.com/athletes/mat_gordon
Strava Support Team


I am uploading the iBike CSV and the Garmin FIT files in case they might provide clues.

Any thoughts or solutions that anyone has will be appreciated.

Thanks,

Robert
Attachments
Garmin files.zip
Saturday & Sunday, May 4 & 5 Garmin FIT files
(429.22 KiB) Downloaded 515 times
Saturday & Sunday iBike CSV files.zip
Saturday & Sunday, May 4 & 5 iBike CSV files
(806.49 KiB) Downloaded 489 times
Davis6022
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Re: iBike import to Strava not grouping with other riders

Post by Davis6022 »

Do you accept the Garmin timestamp when you merge the ibike file with the Newton fit file?

Another thought - will it work of you export the combined file to tcx instead of csv and import the tcx to Strava?

I do both of these and I've not had a problem with Strava not finding the other riders on a group ride.
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

Yes I do accept the Garmin timestamp (this is checked by default during the merge process)

I don't know about exporting to a TCX file but that is just an extra step that I would need to take. Since it (importing the CSV file directly to Strava) worked previously I see no reason to have to add an extra step.

I haven't had a problem with this either until this past weekend (except for the previously mentioned DST issue).

As the Strava support person mentioned "I'm actually not sure what's causing the iBike version to not be grouped appropriately. It's got the same start time and all the same segments - which is the important thing." ... etc. ...

Thanks,

Robert
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

FYI - an update from the Strava support folks

Mat Gordon, May 06 08:58 am (PDT):
Hello-

I do have a feeling this is an issue on our end... I'll see what I can do!

Thanks for your patience.

Mat
strava.com/athletes/mat_gordon
Strava Support Team
texmurphy
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Re: iBike import to Strava not grouping with other riders

Post by texmurphy »

For the past several weeks I have found the quality of Strava finding/matching fellow riders has been decreasing.
This is especially true for riders commuting to a common start point and commuting home from a common end point - but the ride itself will fail to match as it once did.
Strava has also been changing the segment match algorithms so I now seem to match neighboring unridden segments at times.
Of course the Strava Android/iPhone apps are poor data loggers for matching.
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

Here's the latest communication from the Strava folks.
Mat Gordon, May 13 01:24 pm (PDT):
Hello-

Thanks. It looks like a timing issue... Could you check what time settings you have on your iPhone - is it set to use automatic network configured time, or a manual time of day?

Thanks very much!
I replied
Mat,

There is no iPhone or Android device in use here. There is an iBike and a Garmin. The Garmin file is merged with the iBike file and then the iBike file is uploaded.

I just checked and the iBike time is correct and so is the Garmin time.
And Mat @ Strava replied
Interesting... Admittedly I'm not too familiar with the iBike - I was assuming it was the mobile app. The iBike upload is 2min 10seconds behind on every segment start time - that's what is preventing it from grouping activities. Is there any way to double check that?
I told Strava that I would post here and see if I could get any answers on what might be going on. I mentioned that the timing issue may possibly be in the way that the iBike file and the Garmin FIT file are synchronized.
Interesting. I'll pass that along to the folks at iBike and see what they have to say.

I wonder if it has anything to do with the way that they synch the iBike data and the Garmin FIT file data.

Thanks for that detailed information! I will post it to their forum and ask for someone to take a look at it / get a response.
Would definitely appreciate the iBike folks taking a look into this / providing some feedback regarding the issue.

REMINDER: When I uploaded the Garmin FIT file directly to Strava the other riders that I rode with were all grouped together. We were not grouped together when using the iBike GPS synched file that was uploaded.

Thanks in advance,

Robert
FirmwareGuy
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Re: iBike import to Strava not grouping with other riders

Post by FirmwareGuy »

Hi Robert,

The ride time set in the Newton is based on the time that is set in the Newton. It is my understanding that whenever you connect your Newton to Isaac, the time of the Newton is set to the current time of you PC, but I will have to double check this. One of two things could be at play here. Either the time on you PC has somehow drifted off, or it had been a long time since the Newton was communicating with Isaac so the time may have drifted off. I will double check a few things in the Newton code to see how the time is being maintained to make sure there aren't any obvious problems. I will also coordinate with the software developer responsible for the Isaac application to double check how Isaac is setting time on the Newton.

For the time being, I think the best workaround for you is to make sure the Newton time is set to the correct time of day before heading out on you ride.

It would be interesting to know what sort of time tolerance the Strava folks have built into their matching algorithms.

I will post again shortly as soon as I've had a chance to double check things on our end.
FirmwareGuy
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Re: iBike import to Strava not grouping with other riders

Post by FirmwareGuy »

Hi Robert,

I double checked things and it is as I thought. The Newton Time/Date should be getting set by Isaac every time you connect and download ride files. You can also force the time/date to be set through Isaac through the menus.

So, just to make sure your rides get grouped, please make sure you Netwon TIme/Date is set prior to heading out. The software developer that works on Isaac is looking into using the Time/Date information from the GPS file when the data is merged with the ride file in preparation for the upload. He actually thought he was already doing this, but there may be some issue that needs to be resolved.

Please let us know if you still have grouping issues even with the time/date is set properly.
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

Firmwareguy,

When I checked my iBike the time was set properly so I don't think that was the issue. My computer is set to get / synch time via the Internet and I just checked to make sure that it was synched and it was.

I've got a big ride on Sunday with a group of people that will be using Garmins. We will all be starting at the same time and taking the exact same route. We'll see what happens when I upload from the iBike file.

Thanks for checking!!

Robert
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racerfern
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

I'm doing the same thing, merging the Garmin data in Isaac then exporting as a CSV file for upload to Strava. I'm not having issues where others on the same ride don't match up. Most of us ride from our individual house to the common start point and it still matches up successfully.

Try this: Export as a CSV file like you normally do. Now open the CSV file in Excel or your preferred spreadsheet application and look at Row 2:
Col A: year
Col B: month
Col C: day
Col D: Hour (24h)
Col E: Minutes
Col F: Seconds

Now look at the file that you had a problem with and see if the date/time matches up with the actual ride as it happened according to Strava. Also take a look at cell T4, that is the UTC time. For me it's -8, the difference between GMT and Pacific Time. That's about all that can go wrong so see if the data in the CSV file meets your expectations. If not, we'll drill into it further.

FWIW, http://app.strava.com/activities/54907749 this ride has me and one other starting at different spots and still showing the same ride.
Fernando
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

Here's an issue that I've run into at least once before. I don't know how this relates to Strava grouping (or if it even does or not) but it certainly could be.

Did a long hard ride yesterday and went to synch the iBike and Garmin when I got home and Issac seemed to recognize that the ride was synch in the "before" scenario but for some reason things flat lined at about the 5.5 hour / 85 mile point in the ride (see pictures)


Things look great in the "before" but totally out of synch in the "after"
File_Synch_Results_2013-05-19.jpg
File_Synch_Results_2013-05-19.jpg (99.22 KiB) Viewed 24289 times
Merge_Signal_Results_2013-05-19.jpg
Merge_Signal_Results_2013-05-19.jpg (144.99 KiB) Viewed 24284 times
Also attached in the zip file are the iBike CSV file and the Garmin FIT file.

I did not even think about using this as a test for Strava grouping since the files don't seem to synch properly. I just uploaded the Garmin file to Strava.

And just in case you need it, or on the chance that it might help, here is the link to the ride on Strava - http://app.strava.com/activities/55201738

Like I said, I've this this issue before. Any idea why everything (speed, cadence, HR, and elevation) get messed up when Isaac tries to synch the files?

Thanks,

Robert
Attachments
iBike_05_19_2013_0615_112_Miles.zip
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racerfern
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

So the EXACT same thing happened to me yesterday on a 44 mile ride. I ended up deleting the portion of the ride that flat lined and uploading the first 37 miles to Strava. I'll go back and have a look to see if the Garmin 705 TCX file has the error or if something went wrong in the merge.
Fernando
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

I suspect that it has something to do with the merge since the upload to the Garmin Training Center program, the upload to Garmin Connect, and the upload to Strava from the Garmin unit all contain the correct data for speed, elevation, etc.

Robert
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racerfern
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

My TCX file has the info but interestingly enough the failure occurred when I stopped for the coffee break with the guys. For some unknown reason the Garmin did not record properly and I missed the last 6 miles. I wonder if I accidentally stopped recording? Oh well, one out of a few hundred rides is lacking info, however the Newton data is intact.
Fernando
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

I exported from Garmin Training Center to a TCX file and everything appears to be there as well (not really a surprise as the entire ride appears in Training Center and also when uploaded to Garmin Online).

I would agree with you that it's possible that something happens after stopping and then starting again.

On this ride we rode out to about 32 miles and stopped for a bit, then rode on another 23 miles to the top of the climb and stopped for a quick lunch (it's great to have a couple of the guys wives drive sag and serve you lunch after 57 brutal miles with over 5000' of climbing!!), that was at approx. the 57 mile mark. Then turned around and did the reverse, stopping at the same spot on the way back at about the 80 mile mark. But the flatline appears to come a good bit after that 80 mile mark - much closer to the 90 mile mark.

In the CSV file at the 90 mile mark the Longitude and Latitude still seem to be changing until you get to the 94.2169 mile mark (line 20191 in the CSV). After this the Latitude stays at 33.29468 and the Longitude stays at -111.09642 until the end of the file.

Another interesting observation is that the Timestamp stays exactly the same from this point (line 20191) until the end of the file but the moving time keeps incrementing.

So ... what, if anything does that tell the iBike / Garmin merge guru's?

Hopefully those observation are some kind of clue as to what's going on.

HTH ....

Thanks,

Robert
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

OK ... now I think I may have really found something significant pertaining to this issue

Line 13616 @ 56.6588 miles has a timestamp of 2013-05-19T19:17:49Z

I can pretty much guarantee you that's when I stopped at the top of the climb and had lunch.

The next timestamp is 2013-05-19T19:11:57Z

Isn't that going back in time?

The same thing happens when I stopped on the way back at the 81.129 mile mark (line 17220)

Look at the timestamps on lines 17220 - 17224

The time goes backwards on line 17221 and then back more on line 17224

I don't know if that's just a normal function of the synchronization or not but it sure seems a bit strange to me ... It was a really hard ride but I sure didn't feel like I'd ever entered any time warps during it :o

Thanks,

Robert
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racerfern
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

Mine probably has the same error since it happened after an extended stop. I have a TCX file that's easier to edit. If I can get mine working properly I'll work on yours. I'm pretty good at fixing these kinds of errors so hang in there, we'll get it.
Fernando
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

@rstrom

Please upload the iBike ibr file, I can't work with the CSV file.
Fernando
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

Here you go ... have fun ;)
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iBike_05_19_2013_0615_112_Miles.ibr
(2.65 MiB) Downloaded 381 times
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

Fernando,

Just to be sure ... it's not that I need the file for upload to Strava or anything else. From my perspective it's all about trying to figure out why files that should seemingly synch are not doing so.

Thanks,

Robert
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racerfern
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

@rstrom

Oh I get it alright. I have an obsession with making data work even when it doesn't want to work. There are enough programs out there that fix errors, change formats, etc. that you can usually get something to work.
Here's the file as an ibr that you can use as you wish.
BTW, I imported the FIT file into SportTracks, used an error checker then exported it as a TCX. Then I merged the TCX file in Isaac with your ibr file. This is why the Staples EASY button exists. :)

With the ibr you can export to whatever format suits your needs.

Enjoy!
Attachments
iBike_05_19_2013_0615_112_Miles_GPS.ibr
(2.81 MiB) Downloaded 393 times
Fernando
KenS
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Re: iBike import to Strava not grouping with other riders

Post by KenS »

I've had similar problems with merging files jumbling up the timestamps.
There's a possible clue in the graphs in the merge function. The attached one is from a short ride with several stops so you can see the details
The graph from the Newton does not include the stops whereas the one from the Garmin does. So the Newton data appears to be based on ride time whereas the Garmin data is absolute time. Trying to match up two datasets with different time base may be sending Isaac crazy.
If that reflects the data being processed by Isaac then I would guess that after each stop, Isaac detects that the speed profiles do not match properly and starts hunting for where they match again. In doing so it shuffles around the timestamps and this sometimes causes it to go backwards in time.
This would not be so bad if you could choose the Newton timestamps for the output file but I've also found that the Garmin timestamps are always used, after they've been shuffled about.
So one fix would be to ensure that the Newton data in Isaac is based on absolute time and not ride time as it appears to be.
I think there is also a much easier way to match the files that relies on the fact that devices like the Newton and Garmin have very accurate internal clocks.
Rather than trying to match the profiles all along the way it is only necessary to work out the UTC timing offset in each device by matching up the first few minutes of the speed profiles. If one is especially fussy, you could do the same at the other end of the ride to detect any timing drift but so far I've never found any.
Once the offset is known the files can be easily merged by adding the offset to one set of timestamps. I say this because I have done exactly that using a spreadsheet to merge the files after hitting the issue with the errant timestamps. Looking at the graphs below, the offset is about 30 seconds
Merge file graph
Merge file graph
2013-05-18.JPG (203.21 KiB) Viewed 24150 times
-- Ken
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

So the Newton data appears to be based on ride time whereas the Garmin data is absolute time.
Quite a while ago I suggested (it had nothing to do with merging files) that the iBike should keep track of both ride time and total elapsed time as I've always liked to see the two and have seen them on other computers. At the time the iBike folks did not appear to be receptive to the idea. I don't remember if it was just not possible to program the unit to do this or if it just wasn't something that they cared to do.

Either way, I would like to suggest that this feature / functionality be added if it is possible. Besides being a nice to have for everyone, it should certainly help in synchronization with Garmin files.

Robert
rstrom
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

Fernando,
I imported the FIT file into SportTracks
Is that accomplished via the GarminAPIDevicePlugin? A plugin that only appears to be functional in the full version.

Thanks,

Robert
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racerfern
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

Is that accomplished via the GarminAPIDevicePlugin? A plugin that only appears to be functional in the full version.
I don't know because I do have the full version and have never had to do anything special to import FIT files. I simply imported the FIT file you included in an earlier posting.

Have you looked at the file I sent back to you?
Fernando
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Re: iBike import to Strava not grouping with other riders

Post by KenS »

rstrom wrote:
So the Newton data appears to be based on ride time whereas the Garmin data is absolute time.
Quite a while ago I suggested (it had nothing to do with merging files) that the iBike should keep track of both ride time and total elapsed time as I've always liked to see the two and have seen them on other computers. At the time the iBike folks did not appear to be receptive to the idea. I don't remember if it was just not possible to program the unit to do this or if it just wasn't something that they cared to do.

Either way, I would like to suggest that this feature / functionality be added if it is possible. Besides being a nice to have for everyone, it should certainly help in synchronization with Garmin files.

Robert
Newton does record elapsed time as far as I can tell. When you export to CSV you can see the absolute timestamps. It just doesn't save them when the bike is stopped. So the data is there in Newton to display elapsed time but that would require finding a way to activate it (more button presses, screen space, memory etc...) which means firmware changes and I suspect Velocomp has bigger priorities like Powerstroke etc...
The merging problem is really an issue within Isaac which is either using the wrong timestamps or processing them wrongly.
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

@KenS

You're right, the issue is within Isaac. It's not easy to merge two data streams with such different info. Newton does not in and of itself record the time of day (other than the timestamp as part of recording when the ride started.

The timestamps you're looking at come from the merge with a GPS device.

That said, I believe the merge uses cadence as the common signal to merge files which makes sense although errant time stamps within the GPS file will always be a problem. It seems every time someone (including myself) has an issue like this it's when there is an extended stop for a lunch, or something like that.
Fernando
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Re: iBike import to Strava not grouping with other riders

Post by KenS »

But if you look at my attached CSV file which is exported from a .IBR straight out of the Newton (no merging, no other processing) it has a column O with a Timestamp in UTC whereas column N has Moving Time. Look at rows 92 and 93 and you see a gap more than 1 second (22 seconds in fact) in the UTC stamps where I was stopped, whereas the Moving Time ignores this. So Newton is in fact recording absolute time as well as ride time.
This file corresponds to the graph I posted earlier so you can see that 86 seconds into the ride for iBike I stop but there is no wait shown. For the Garmin, the stop happens at about 120 seconds because I paused for 30 seconds at the start of my ride. But the Garmin graph in red shows the 22 second wait clearly. Same thing happens at 109 seconds on the iBike and about 160 seconds on the Garmin. Note that the Garmin is now 50 seconds behind the iBike due to the missing 20 second
iBike_2013_05_18_1237.csv
Exported iBike file
(67 KiB) Downloaded 401 times
Based on what I see on the merge graph, the reason we have issues around stops is very likely because the merge program is using the Newtons Moving Tme info instead of absolute time and trying to compare to the GPS absolute time. Now that is hard to do as the program needs to resynchronise at every stop.
On the other hand, matching with the same time base is not very hard at all. I've done it many times with a spreadsheet using the speed info - similar to the way Isaac does. But instead of trying to synch up the files at every stop, with my spreadsheet I just match up the first few minutes (using a least squares fit on the speed profiles) to establish the time offset between the two files and shift them accordingly.
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Re: iBike import to Strava not grouping with other riders

Post by rstrom »

Fernando,

Yes I have, thank you very much!

Robert
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Re: iBike import to Strava not grouping with other riders

Post by racerfern »

KenS wrote:But if you look at my attached CSV file which is exported from a .IBR straight out of the Newton (no merging, no other processing) it has a column O with a Timestamp in UTC whereas column N has Moving Time. Look at rows 92 and 93 and you see a gap more than 1 second (22 seconds in fact) in the UTC stamps where I was stopped, whereas the Moving Time ignores this. So Newton is in fact recording absolute time as well as ride time.
This file corresponds to the graph I posted earlier so you can see that 86 seconds into the ride for iBike I stop but there is no wait shown. For the Garmin, the stop happens at about 120 seconds because I paused for 30 seconds at the start of my ride. But the Garmin graph in red shows the 22 second wait clearly. Same thing happens at 109 seconds on the iBike and about 160 seconds on the Garmin. Note that the Garmin is now 50 seconds behind the iBike due to the missing 20 second
iBike_2013_05_18_1237.csv
Based on what I see on the merge graph, the reason we have issues around stops is very likely because the merge program is using the Newtons Moving Tme info instead of absolute time and trying to compare to the GPS absolute time. Now that is hard to do as the program needs to resynchronise at every stop.
On the other hand, matching with the same time base is not very hard at all. I've done it many times with a spreadsheet using the speed info - similar to the way Isaac does. But instead of trying to synch up the files at every stop, with my spreadsheet I just match up the first few minutes (using a least squares fit on the speed profiles) to establish the time offset between the two files and shift them accordingly.
I have never exported an ibr file to csv without merging the gps data so this is the first time I'm looking it at this way. Very interesting. I assume you are in Australia with a UTC of +10 (Cell T4). However you have to know that the ibike clock is set correctly. I still think cadence matching is a better way but some allowance needs to be made for poor GPS info.

Regardless, I can't complain too much, hundreds of rides and one miscue? I'm happy.
Fernando
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