At 60miles an hour you could cover 480 miles in 8 hours which is about (if not less than) what the journey would have been at the time. Given he told me he left at 5am I find it quite plausible that he'd make it back to 'London the same night'.
Think I'll believe his account over your opinion but thank you all the same.
Well, maybe, but time lends a certain romanticism to these events in the past. The poorly lit, badly (non) sign-posted roads, and a dim 6V black-out headlamp all with an old bike of the 1930s casts a bit of doubt over the plausibility of this particular tale. Sixty average MPH would be a good figure now, never mind under those conditions.
Not saying the old boy is full of BS, but the journey times have possibly shrunk with the passing years, and maybe he actually started late afternoon and arrived some time the next day?
Something I noticed with my old Dad (now gone) was that in later years two (or more) tales ended up being rolled up together into one in his memory, and that one tale being rather tall gave the game away.....