I've recently bought a new bicycle for my daily commuting and fitted my old bicycle with studded/spike tires as a dedicated winter commuting bicycle. (They're Schwalbe "Winter" tyres, not "MarathonWinter" as I initially wrote on Twitter. I'd have bought MarathonWinter, but they're not available in 16".)
Now I wonder when I should choose which bicycle (both are Bromptons), especially under which weather conditions?
I've seen and read When are studded tires necessary?, but on the one hand the question's focus is a little different and on the other hand, none of the answers really answers my question.
A little background:
- Two years ago I had a self-caused bicycle accident on a dry and sunny winter day due to snow melting, flowing over the street and there freezing immediately again.
- I've thought about using studded/spike tyres for quite a while and after that accident I'm sure that there are cases where they would help.
- I live in a hilly city (Zurich) and there are a few weeks per year with snow and icey conditions, usually in January and February.
- I have been convinced that riding with studded/spike tyres all winter long is a bad idea if most winter days are probably fine for normal tyres, so I've come to the two-bicycles solution to be able to decide on the right tyres without any time penalty for switching wheels.
- Since my commuting bicycle is a Brompton with six gears and dynamo hub, switching wheels in the morning depending on the weather isn't an option anyways.
- When I fetched my winter Brompton from the mechanic and did a test drive with the studded/spike tyres, I noticed that they're really loud and that indeed will only ride that bicycle when necessary.
- I don't care about rolling resistance or possible speed. My daily commute is a inner-city ride of about 5km.
So far the winter was really dry and there was no need for studded/spike tyres.
But when should I switch to my winter bicycle with studs/spikes? My current idea is the following:
- When there's snow or snow mud on the streets. (Deep snow is seldom and usually gets cleaned up rather fast, but there's often still a thin layer of slippery snow mud on the streets, especially if the city runs out of gritting/thawing salt.)
- When the previous days were rainy and the weather forecast talks about freezing temperatures. (→ chance of water freezing over)
- When a sunny day follows cold and snow days to avoid the case where I had my accident two years ago. (→ chance of water freezing over)
Are there any other conditions on which I should use studded/spike tyres? Or am I overcautious due already having had an accident on unexpected ice? E.g. many years ago I easily survived this kind of weather with normal Schwalbe MarathonPlus tyres.