As I live fairly close to Lutterworth I thought I’d try and give you a different perspective to some of the replies so far – I’m assuming you already know there are no mountains nearby, and that if you want techy gnarr you’re going to have to travel.
Having said that, there is a vibrant MTB scene in South Leics. There are lots of informal groups that ride out from the local villages and several well run clubs on your doorstep including Welland Valley, Rugby Velo and CATS MTB. The Friday Night Summer Series is reckoned to be the longest running MTB race series in the country, and whilst it’s serious at the front, at the back it’s just a ride before a beer or two afterwards.
There is some reasonable riding in the Warwickshire direction, but I think the better option is to the east. If you get a map and draw a circle moving clockwise from Lutterworth through Fleckney, Kibworth, Market Harborough, Desborough, Rothwell, Birixworth, Crick and back up to Lutterworth – then look inside that circle. You’ll see a large area with miles of bridleways that can be linked using just country lanes, all of which you could ride from your doorstep.
It’s probably too far to ride from your doorstep, but if you go slightly further east you’ll find more good riding – draw a circle clockwise from the eastern edge of Leicester through Oakham, Uppingham, Corby, Market Harborough, Kibworth and back up to the eastern edge of Leicester – and again look inside that circle and you’ll see miles of bridleways and in this area it’s possible to build quite long loops that take in some reasonable hills.
A good thing about these areas is they’re rideable all year round – the bedrock is all gravel so it drains really well. Having said that, how much you enjoy it will very much depend on what floats your boat. If you only enjoy MTB when the trails are steep, rocky and challenging to ride then you’ll not get too much from the area. On the other hand if you enjoy getting out into the countryside with mates and messing about on bikes there’s lots of fun to be had.
If you ever get in the Fox (bottom of the hill into Lutterworth) on a Friday night you might see a bunch of guys drinking too much and regaling each other with tales of mountain bike daring- do, if you can ignore the bullshit do come and say hello!