I think my coldest ride was in 1964/65, 3 of us went to the elephant rally, at the nurburgring, just before we left to make our way home, we had a flat rear tyre, it was snowing really heavy, by the time we got it repaired, it was getting dark, we were on a BMW boxer, and the snow was coming over the cylinders, every mile or so the plugs shorted out and we had to clean away the snow and start again, it took us 10 hours to get to zeebruger to catch the ferry home to england. but by this time the clutch had given up. When we got back to england, we had to bump start the bike, run and jump onto the back of the bike, as once it was moving it couldn't stop. we rode right round the london ring road, to get to the M1 motorway, when we reached the slip road, to join the M1 it looked like a giant runway, as there were no central reservation at that time, and it was covered with snow, it took us another 8 hours to get up to Nottingham, a distance of about 120 miles when i got to bed i slept for 48 hours.