Mark Cavendish, the best UK cyclist?

But the Isle of Man is not a part of the UK, it's a Crown Dependency, that's why my passport says "British Islands, Isle of Man" PLATINITRUFAX

Cav also has full British Citizenship.

Best (dead) UK cyclist? How aobut Tommy Godwin.

http://en.wikipedia.org/wiki/Tommy_Godwin_(cyclist_born_1912)

Holds the record for the most miles covered in a year: 75,065 miles.

Yes. 75065 miles. That's an average of 205 miles a day, every day for a year.

Not happy with that, he carried on to get the record for the fastest 100,000 miles by continuing on until May 1940. Then what did he do?

"
Godwin dismounted and spent weeks learning how to walk before going to war in the RAF.
"

That's proper HTFU.