In reply to abr1966:
BTW - assuming you do take everyones advice and go to Whinlatter, then be aware that it's easy to miss out a big section on the South Loop
I say easy, the signing may have improved and it may just have been me with my head in the clouds, but I went round once, thought that was a bit shorter than expected, went round again and still didn't realise anything was amiss until I had a look at a trail map that evening.
Also, there's quite a good BW from Whinlatter down to Portinscale, but be aware that drainage ditches are quite savage and can easily rip the nobbles off your tyres, which is particularly fun if you riding down in the dark.
Another reason for going there is that the café is handier than at Grizedale - so if you've got a mixed group people can always sit out a lap