Originally Posted by
Grumpy McTrumpy
10 miles is common.
20k is also somewhat common.
40k is the most common championship distance, as you mentioned.
+1
Also super common in FL are the super short 3-4 mile TT's which are part of the very few stage races here.
I have rarely seen a 40k TT as part of something other than championships or stand alone TT's in amateur racing.