Clifton CC

What about this!

http://www.oneupcomponents.com/

Works on 10 speed 1by systems by droping the 17t sprocket.

Any thoughts?

It's interesting Simon.
Looks like it shifts the standard “10-speed-built-for-2-chainrings” cassette up one cog to this new 42 tooth, to make cycling up hills easier on just one chainring.
A low cost way to get the same wide gear range of a 11x1.

And then sell your front mech and shifter, to bring the total cost of converting to 10x1 down to just £20!

Here’s a gear calculator if anyone is thinking about trying it: http://sheldonbrown.com/gears/

… Or you could just try getting fitter, and then you wouldn't need to use a cassette the size of a dinner plate!!

Paul,Paul,Paul.... The problem with "1 by" systems is the high gear not the low gear!

Fitness always helps whatever gearing sysem you have but on "1 by" gears a dinner plate rear sprocket enables a 36 or in your case a 40 front ring, that with the 11 on the back gives more speed down hill