Hi – after someone tried but failed to nick my bike I need a new lock , I had a kryptonite cable lock which is still useable but want to replace it. so for under £50 what's the best thing to buy, going to pair it up with a kryptonite cable to lock all the wheels etc.

I'd spend as much as you can on a U lock from someone like Kryptonite or Abus, don't really believe a bike is secure unless you run both a U lock through immoveable object, rear wheel and frame and a cable lock through everything… I have a kryponite mini evolution ulock and a cable lock, think I should have got the standard sized Kryptonite evolution as the mini is a bit too small sometimes…

Go for abus granite IMO. forget kryptonite. £50 is the bare minimum to spend on a decent U lock

Second Abus. I got one of the "new" Kryptonite locks that they brought out in the wake of the biro debacle, for clipping on to the work/pub bike. It's worked OK as a lock, but the bracket for mounting it to your bike is useless, the rubber bumpers that are meant to stop it rattling don't do anything, and the ridiculously wide key comes with a warning about breaking it off in the lock!

£50 is the bare minimum to spend on a decent U lock

Depends what you're locking up. I know that would double the value of my hack bike, and pretty much all the components could still be removed from the frame by a minimally tooled-up thief. I've seen a cheapo D-lock like this being picked but any decent "name brand" lock will be pretty good.

thurded for abus granit.

I own three of them.

I have a Kryptonite lock (the silver one) from the post-biro era.

It mounts fine on my commuter.