Re: I can't find a gear...any ideas?
If there is absolutely no resistance to movement, its the gear linkage I would say.
It could be something as simple as the little swivelly bit at the end has just come off the ball its attached to.
Not sure where it is on a twinney, but it should be visible looking down the back of the engine. Its likely you will see a strong looking cable disconnected from it.
You could reattach this by hand easily, although it would be likely to happen again until fixed properly.
You can replace just the bit that attaches onto the ball at the end rather than the entire linkage, although I'm not sure can you purchase it seperately. I think the linkage is about 60 quid or something, but labour for full replacement would eb more.
Replacing just bit that clips onto the ball is 5 minutes work.
I'm not a doctor - but I really do recommend braking later