|My son is always ready with the snow shovel.|
About when this was all starting, I actually went out with a 60cm/2ft level and tape measure, and made a few measurements of the slope that I need to haul my son up, to reach his daycare. Of course I didn't want to spend too much time looking ridiculous measuring the public path, so I only measured the most interesting spots. To jump to the numbers, I can now say that I have definitely climbed slopes over 25% with two kids in the box (lets say 50kg of cargo total) on my 15 gear-inch Nihola. I can also confidently say that a 15% slope is doable with the same load on my 21 gear-inch Nihola (with a Shimano Nexus 8 hub, nothing exotic). So thats good to keep in mind. Niholas can do hills.
The more interesting question to a year-round utility cyclist might be how steep of a slope can be managed when its covered in snow. I've been testing this the past three weeks, but first a little about the hills I've been climbing. On the way to the daycare, there is in fact a small bit of 25% slope, rising suddenly after a tunnel under a road. This flattens to nothing in 40m or so, but its a definite problem spot. After some modest climbing, a 200m stretch that is up to 10% slope starts, then a stretch of 70m at 12% slope, with a measured max of 15%. Overall > 50m in < 600m with an average slope of 8-9%. On the opposite side of that hill, without children, I climb/descend 175m in 3km with slopes up to around 15%, and once in this period I also took a long way home, which ended up being un-plowed for 2km averaging 3% slope. Now none of this is epic on the scale of hills where snow accumulates, but its plenty hard enough, and since I don't see a lot of people doing it, I might as well share what I have observed. Perhaps people think its harder than it is.
First observation: I can pedal my Nihola some places and conditions where mountain bikes carrying no particular cargo can't be ridden. I shouldn't be too proud of myself; sometimes it might be faster to just pick up a bike and walk, than grind through the snow on a trike. But anyway, if a person is intent on bringing their trike with them, it can be done, and it doesn't involve falling over.
|This unstable snow caused a lot of trouble for bikers.|
The dark mark is where someone had to fight to remain upright.
|This amount of new snow was no particular problem, even with a shifting foundation underneath.|
The condition of the road surface is of paramount importance. On the same section the following day, I had a lot of trouble with the other Nihola. In that case, the snow was fresh (less than an inch), the temperature was more like -5C/25F, I had closer to 37kg in front, 10kg in back, a more impressive Nokia Extreme (26x2.1) rear tire, and 15 gear-inches to work with. I had to make multiple attempts at the climb, and only succeeded on the less-steep side of the path and with significant tire slippage. As the days passed, I continued to climb that nasty spot through various forms of snow, and generally higher temperatures, up to icy melting conditions this morning. In looser snow, this often meant spinning and digging, with very slow progress and sometimes with rolling backwards to use the excavated trench to build a spot of inertia. This morning with maybe 17kg in front and 6kg in back (I weighed my bag to see), on wet soft ice, I needed a run at it to clear the steepest parts and could make a little progress from a standstill somewhere over (estimated) 15% slope. I was carting both kids up the hill, and the older one had to walk there. Three-wheel balance allowed me to thoroughly confirm that there was no way I'd make it with both kids; usually after a run I was sliding backwards with all three wheels locked up.
|Here, the rear tire has scraped up snow shavings from a hard-packed surface.|
|Here we have dug a trench in semi-packed snow.|
Heavy load in front, not much on the rack.
I met various forms of snow in these three weeks, from unpacked to hard packed, and with lots of foot-trodden mushy middle ground. Obviously hard packed is preferable, but when that was not available, I was not able to determine if it was better to drive where people have made a mess, or where the snow was undisturbed. Lots of slow work in both.
On soft ice, the advantage of 15 gear-inches is reduced compared to something more like 20 gear-inches, because it was necessary to be very careful with the torque, to maintain traction. On the other hand, having really low gears allows comfortable crawling while waiting for all the kids sliding down the icy hill to get out of the way. Its best to keep moving, rather than stopping. Rolling the pedals backwards was possibly essential in really delicate situations, to avoid breaking traction and starting a backwards slide.
I suspect that hauling kids around on hills in the winter is not an activity that is about to go mainstream.
|The snow is melting away, and messy.|