In the exchange of views we have all had about fat bikes using the VASA Trail, all sorts of opinions have been expressed, from “there were crazy scary ruts” to “the effect on the trail ranged from not detectable to smoothing out skater marks.” I thought some more objective information might be helpful.
Cyclists generally say that, at temperatures 30 degrees or below, there should be no problem with fat bikes causing trail damage when riding on groomed, hard packed trails, but that at temperatures above that there are concerns, particularly if the snow is soft or just groomed. I think that is because, with almost 4 inch wide tires, if fat bikes are going to make ruts, they make big ones. Traverse Area Recreation and Transportation Trails Inc. (TART) simply says, "if it is above 30 degrees you should not be riding on the VASA Pathway."
The charts which follow, from www.weatherspark.com, show the weather in Traverse City for the past few years. Temperatures below 15°F are purple, 15°-32°F is blue, 32°-50°F is green, 50°-65°F is light green, 65°-75°F is yellow, 75°-85°F is light red, and 85°-100°F is medium red. Basically, during the ski season (December 1st to April 15th) purple or blue – fat bikes should be just fine (except for possible collision/safety concerns on our narrow trails if shared with fat bikes), green – you shouldn’t be out there on the trails.
Trailing 12 Months – “THE POLAR VORTEX” hourly temperature bands
2013 calendar year hourly temperature bands
2012 calendar year hourly temperature bands
2011 calendar year hourly tempurature band
You can draw your own conclusions from these charts, but I think it is important to remember that we are coming off one of the coldest winters northern Michigan has seen in many, many years. In fact, between January 15th and February 18th, there were 35 consecutive days the temperature never got above freezing. Outside of those dates last winter, there is a lot of green on these charts! When we did see trail damage last winter, it occurred on one or two days when it was above freezing, and it only took one or two fat bike riders to cause the damage.
At present, as I understand it, TART does not have the authority to close the VASA trail to trail users because of weather related trail conditions. So it seems to me these charts suggest that it would take a very well organized self-policing effort by cyclists, to make this work, if it even can be made to work. It’s a lot warmer here than it is in places like Giant’s Ridge Ski Resort in northern Minnesota where fat bikes and skiers do successfully share the same trails...