A heads up on the Eurostar - there will be a maximum of 8 places available for bikes on any train (it's only 4 on some trains) but if the train is already booked up they will guarantee that your bike will arrive 24 hours (maximum) after you do. If there are lots of you travelling you might have to A) hang around at Kings X for your bike to come on a later train. B) come back to Kings X the next day to collect your bike.
A heads up on the Eurostar - there will be a maximum of 8 places available for bikes on any train (it's only 4 on some trains) but if the train is already booked up they will guarantee that your bike will arrive 24 hours (maximum) after you do. If there are lots of you travelling you might have to A) hang around at Kings X for your bike to come on a later train. B) come back to Kings X the next day to collect your bike.