|The bearded one has spoken...|
Mudguards are required during winter (when the clocks are at GMT).
This means full mudguards with a mudflap that covers the rear wheel to at least the level of the rear hub.
Mudflaps can be made from a variety of things. Google is your friend here: http://bit.ly/1Ef6SNf .
Mudflaps are to cyclists like light-sabers are to Jedi- having one shows you are the real deal. The more elaborate and longer coverage, the greater your cycling powers!!
You will NOT be 'kicked off' a clubrun without them. There is also a ''no mudguards" group that meets at the same time as the clubruns, and is listed on the calendar.
If you go with any other group, you will probably be asked to ride at the back and be subject to some gentle ribbing from people with mudguards. After all, not everyone likes chewing on Belgian toothpaste for hours at a time.....