The Fat Unicyclist Posted November 20, 2016 Share Posted November 20, 2016 I'm not sure of the best place to put this post, so I am going with the IPS section, and will link it back to other relevant places... So today I rode my Lhotz from a full charge, directly uphill to check how it handled (while monitoring the stats). Leg 1 - Uphill Starting elevation: 100m Starting charge: 100% Starting temperature: 16°C Starting load: 115kg Finishing elevation: 250m Finishing charge: ~70% Finishing temperature: 49.5°C Distance travelled: 2000m So I wheeled hard on the uphill, while watching the stats. I wanted to see what the point of failure was... And while I expected my wheel to beep me (requesting a rest) I expected it to be due to the temperature - but the reality when I got the warning was that the app was showing the battery status as <15% but the temperature was still less than 50°C. But after stopping, and allowing the wheel to recover, the status ramped back up to around the 70% mark - so after a 30 second stop I was good to go. Now I should point out that this was 1800m (at pace) into the trip, and I did not let up at all along the way (though I may have slowed down a little as I passed the bakery to check out my options for the second leg). Previously I wasn't sure whether I needed to stop due to temperature or battery drain, but this is now confirmed. I am expecting to take some flak for this, but my statement now is that, "For a heavier rider going uphil, the battery drain can be more significant than the temperature." And in my case, the load became the limiting factor well before the temperature was an issue. Interestingly, it wasn't a torque issue, as the wheel still had a lot of pull in it, but it just didn't have enough stored energy available to draw on to power through? Is this a limitation of the battery technology? Leg 2 - Downhill This was a bit more experimental... The IPS app kept crashing (and I don't think I can use WheelLog) - It seemed to crash particularly when I was on the steeper downhill sections. I wonder if this was when the motor power was a negative value (regenerating) and it didn't understand how to present that? But what I did notice is that while the app showed power usage around 15-20% (while travelling ~10km/h) I did end up at the finish line with the battery charged to around 80% . Overall, my observations (and feeling) makes me think that on the "shallow" downhill, I am still using power to actively drive, but on the steeper sections, power is flowing back into the battery as one would expect. My conclusion is that, at slower speeds with a heavier load, it requires a steeper gradient to achieve regenerative power - and a percentage is actually used on the shallower gradients to maintain a constant (slower) speed. And continuing on that thought - I was interested to note the "stopped" effort - on the flat, I can hold onto something and the motor power to keep me upright is 1-3%. But on a good hill, it is 10-15% Okay, that is me - everyone feel free to shred my comments with science - I am more than happy to be wrong, I just want to understand all of this more! Link to comment Share on other sites More sharing options...
This topic is now archived and is closed to further replies.