We have a carry bag for our Secret bike,please give someone a ring at Kudos. It has wheels like a wheel on aviation bag,£29.50 from memory.
Dave
Kudoscycles
Ian, if you mean a bag to put your folding bike in.. assuming it's 20" there's a good one sells for £22 with free delivery on Amazon which gets positive reviews...also folds up and stows under the saddle.
I used a Sport Direct bag for my Brompton (before the bike was stolen). It was pretty much a perfect fit. Price 59 pence. The bag was made of a similar material to IKEA bags and plenty robust enough for carrying the Brompton. You can see it here.. SportsDirect Medium Bag 4 Life - Sports Direct
I take delivery of my new Brompton at the end of the month. The £995 P6R model which I have managed to get for £675. I am well pleased. But that's another story. It will be carried about on buses ( to avoid exciting the bus driver) in a new Sport Direct bag.