15 kilometers on steep hills with my Hill Topper

I have now completed the test ride of my newly installed Hill Topper Conversion Kit. Some juice remained in the battery even after 9.32 miles (15 kilometers). I used Topeak V10x bicycle computer to measure my ride.

I rode with a total equipment weight of about 30-35 kilos. That is assuming my bicycle with the heavy battery and motor hub has a total weight of 25 kilos. I pulled an empty 10-kilo child carrier when I did the test ride. If I add my weight of about 59 kilos, the total riding weight is between 89 - 94 kilos. Surprisingly, the motor can still spin the front wheel with this weight even on 18% grade hills as long I assist with pedaling.

I want to record my climbs accurately but my bicycle computer does not include an altimeter, so I searched the net for some ideas. The important thing in measuring climbs is to measure the grade of the hills.

One anecdote says that you know if the grade of the hill is more than 10% if:
a) your legs are burning
b) your lungs are about to explode
c) you are about to pass out and roll into a ditch.

I surely don't want to try that method but I did feel that way before when I tried to climb one hill on a paved road for the first time. I later found out that that hill was actually 10% grade, with about 97 meters ascent. That climb is more than 2 kilometers long and takes me 15 minutes to pedal. I start to feel the 3 conditions hilariously described above at 1.5 kilometers on my climb. This was when I have not installed my Hill Topper Conversion Kit yet. It took me about 2 weeks of climbing that hill everyday until I got used to it. I pace myself to avoid the 3 things in the anecdote. It gets very heavy by the time I reach the steepest part of the climb with the 18th of my 27 gears engaged.

Now back to my Hill Topper test ride. Since I'm not sure if I have measured my test ride correctly, I also consulted MapMyRide.com. Here are the details that came out from that site's calculations:

Total distance: 8.5 miles
Start/End elevation: 101.9 meters above sea level
Highest elevation reached: 136.5 meters above sea level
Ride distance accumulated at highest elevation: 2.5 kilometers (1.55 miles)
Accumulated ascent at highest elevation: 34.7 meters

Grade of hills
First hill climbed spanning 844 meters: 6% (16-meter ascent)
2nd hill climbed spanning 830 meters: 10% (30-meter ascent)
3rd hill climbed spanning 630 meters: 6% (13-meter ascent)

4th hill climbed spanning 980 meters: 18% (81-meter ascent)
I used the motor assist all the way on this 4th hill while pedaling with the 14th gear engaged (note: I have a 3 x 9 gears or a 27-gear set up, so the 14th gear is actually 2 x 5).

5th hill climbed spanning 130 meters: 7% (2-meter ascent)
6th hill climbed spanning 740 meters: 3% (9-meter ascent)
7th hill climbed spanning 191 meters: 12% (7-meter ascent)
8th hill climbed spanning 141 meters: 12% (7-meter ascent)
Last hill climbed spanning 140 meters: 9% (4-meter ascent)

The average steepness I engaged the motor with is 8.12 % grade. Since I covered 4.6 kilometers of climbing with the motor on my test ride at 13 kilometers per hour speed, I would say that the test shows that the motor can last (with the same climbing power as a fully charged battery) on a 8.12% grade average hills up to 5 kilometers (3.1 miles). That's 30% of the Hill Topper's advertised capacity in a presumably flat riding condition. That is, if I ride my Hill Topper (using the standard Sealed Lead Acid SLA battery) on flat roads without hills, it should last with the same full battery power for 10 miles (about 16 kilometers). Assuming the speed is constant at 30 kilometers per hour, that translates to about 30 minutes of riding time. In my test ride, the power stayed on for 40 minutes but my average climbing speed is 13 kilometers per hour with pedaling.

I felt the motor losing its power after about 11 kilometers (6.8 miles) of engaging it on steep climbs.

I am generally satisfied and happy with the results, especially because I still got to exercise and pedal on steep climbs, but without the heavy panting and without feeling very tired. I did not have to dismount my bicycle even if I was climbing an 18% grade hill as long as the motor is engaged and I still pedal with the 14th gear engaged. Of course, the downhill rides were also fantastic.

NOTE: More posts on e-bike conversion projects are available here.