Unless you could crimp on a new waterproof connector. I wonder if Maplins do that sort of thing?
I've had a thought:
I might try cutting the finger off a rubber glove and then cable tie it over the speed restrictor link. That way water and dirt will be kept out of the connector, but I hopefully will be able to connect and dis-connect the link through the finger of the glove.
I don't know if anyone has any thoughts on this?
Ian