Spam?

Yeah maybe not as bas ax I thought

To expand a bit more on my previous comments, in my case bicycling is just fine.  But walking can be bad.  I often find myself walking a bike up a hill.  And on my feet several hours after I make a campsite.  And usually take a couple hours from waking up to finally rolling out of a campsite and some of that time is standing or walking.

So, I chose not to risk a bike trip, not because of they cycling but because of the off-bike time when I am walking or standing.  There were other unrelated reasons I did not do a bike trip too. 

You might consider backpack rain covers. There’s a large selection of colours/sizes from Amazon,  and no doubt other retailers. Not a complete solution because the red would still be there when the covers have to be removed!

I can see two Raven tours on Gumtree, one in Edinburgh and one in Chepstow. Suggest you have a go logging in to Gumtree.com and search, Thorn bicycle, and they should appear.