Weekend Ride: Hills & Di2Stats

I had an interesting ride over the weekend. I seem to have passed some cycling competency test or other and was allowed to move from the banks of the Thames to the hills of Surry and Sussex (Southern England, below London).

As well as seeing how much time I could spend in ‘first gear’ (34:28) it was, of course, also a time to make my carbon-framed bike as heavy as possible with 1-1.5kg of water bottles and numerous pieces of electronic wizardry.

Electronic Wizardry?

I mean, of course, watches and bike computers.

All four of the weekend’s devices seemed to play nicely together even broadly agreeing at how high above sea level they all were.

Like this…

I only have a passing interest in elevation details but one ‘tip’ is that you can apply post-ride elevation corrections to your workout. Lots of sports software does this.

In Garmin Connect, for example as shown on the right,  all you have to do is simply enable ‘elevation corrections’. The software then goes off and cross-references every GPS point on your workout with a database that ‘knows’ the elevation/altitude of those points. Hence your records of ascents are always ‘correct’. IIRC Strava is the same kind of thing, so you’re probably already seeing ‘correct’ values anyway, without realising.

Of course these are all post-workout changes that are made to the data. The metres-climbed shown during your ride could well be wrong. If you want to make in-ride data more correct, then some of the higher end Garmins will autocalibrate elevation to rider-specified elevations of POIs as you ride through them.

Obviously if your GPS position is wrong then the adjusted elevation will also be wrong. And I think I’m right in saying that the way the data is collected in mountainous regions may mean that the GPS-to-elevation mapping is not quite right.

However what I sometimes do is make a copy of the best GPS track I have for a workout and then apply the elevation correction to that workout. I can then compare the ‘correct’ workout with the elevation profiles from any other device I’ve used at the same time (as shown above). I use various plugins from SportTracks to do that…Other methods, no doubt, exist to do comparative stuff.

Image source (above, on right):https://www.broleur.com/top-10-toughest-climbs-in-the-surrey-pyrenees/ … the link does what it says in the name. You know what to do.

DCR Has Made me Nervous.

After a recent ride (link to my Tour de Yorkshire post) DCR commented that my Di2 shift rate looked high, possibly as high as once every 7.6 seconds over several hours. I am very nervous of this and have now become quite self-conscious. Especially because changing gear with Di2 audibly broadcasts to my fellow riders that it is the electronic ME who is shifting. Maybe they all think I change gears too much? Maybe they talk about me when I’m not there?

Or maybe they don’t care at all. Yeah. Probably that.

Maybe this explains all those strange looks I keep getting when cycling? Or that could be two cycling computers and two watches….hmmm…maybe.

But anyway, self-conscious cycling aside, I do like to do a bit of statistical, cycling psycho-analysis from time-to-time.

As my weekend’s ride was another ‘long and hilly one’ it seemed appropriate, once again, to visit di2stats.com. If you thought you already have too many stats then you are wrong.

Only when you regularly visit di2stats.com will you have too many stats 😉

Big/Little chain ring seems a good place to start….image to right

But the key stat for me to look as was the time between shifts

This still looks in the same ballpark as the TdY ride, linked to above. Conclusion: I just seem to shift gears a lot.

My contention therefore must be that I am super-efficient and fully aware of the road conditions and my cadence and hence shift gears accordingly to maintain optimal efficiency (err…yeah …right…maybe…not)

I had a quick chat with Mr Google to see how frequently pro’s change gear. I’m hoping it will be exactly once every 12.2 seconds, like me. But I couldn’t find any evidence to support my fanciful assertion.

Serious point: If you know how frequently pros shift gear with electornic kit (SRAM, whatever), I’d like to know (below, ty). And one of the ‘selling points’ for Di2 is that the correct gear can be more easily selected (psychologically easier).

To finish up with di2stats.com here are just 2 images that indicate the uber-depth of di2-detail on offer

And this

So if your boss/life partner has just left the room and you have an hour or so to kill; I mean, “invest in improving your cycling knowledge and technique“, then you know what to do: visit di2stats.com

Apparently UK Business Productivity is low. I wonder why?

Di2 Battery Life

As a consequence of my finger-twitching, gear changing riding style I ran out of Di2 battery. Grrrr

My Wahoo Elemnt (reviewed here) did give me a 10% battery charge warning but I was half way up a hill in Surrey with an hour or so to go and there was little I could do about it. So I ignored it. I thought I would make it…but didn’t.

Actually it wasn’t so bad. Di2 seems to enter an ’emergency’ mode once the battery further depletes. This mode stops front ring shifting and fixes you into the smallest front ring. So I had 30 minutes or so of spinning like crazy on the final flat bit going to the end of the ride – I had lost 11 gears but still had 11 and it was flatish.

I did attempt to charge up my Di2 a few days before the ride but what I did was to put the USB charger into the output of a laptop computer (plugged into the mains power). I suspect that didn’t charge either ‘at all’ or ‘efficiently’.

To finish: One thing I will look at (for me) in the future is if these stats change if I use the various synchronised gear chaning options on Di2 ie these should ‘properly’ change gears when a front ring change is made  Here are some images of the Di2 charging bits that I failed to use properly before my ride. If you are going away for a cycling holiday…DON’T FORGET THE CHARGER.