Does your bike have a wheel misalignment when folded? Because right now, my wheels come apart when rolling.

To clarify, my bike is a b'twin tilt 500 with a catch system that supposedly keeps the wheels together. Nowadays, it fails to keep hold of the wheels for more than a revolution.

Any ideas, suggestions or past experiences to help please?

Would a velcro strap work for you?

Most folding bikes have the same issue when folded,... As suggested, use a velcro strap.

... and tilt it so you roll it on only one wheel, not two.

I'll try the tilt thing above but the velcro strap is impossible because of the catch system it is built in with.

Can't post any links either yet since I'm new.

I have a BTwin tilt 500 & had the same problem. The clip bracket the bike folds into can be adjusted. It needed doing on mine & all is well after adjustment. Same goes for the handlebar stem side.

Wait really?

Last time I checked, there weren't any screws or nuts to adjust them except for the front wheel's ball.

The clip side the ball joint goes into is where the adjusting screws are, that's where they are fixed to your frame, should be the same on all tilt 500 models but who knows

Surly Junk straps.. they're a super long with a toe-strap buckle .

Use the velcro to keep it closed,...strap the front fork to the rear of the bike frame. The wheels will still roll. There's nothing special about the fold,...use the velcro strap right where the connecting latch is.

You're right, they can be adjusted! Just checked on mine this morning and all's well and good now. Thanks!

Keep the velcro strap in mind,...just in case. I carry some with me when I use my folders. It comes in handy when you least expect it.

Pleased to be of some assistance, however I would still take the precaution of carrying a Velcro fastener just in case.
I know there is at least 2x Btwin tilt 500 owners on here. If there are any more wouldn't mind starting up a new post on the pros & cons of this bike. It's not all bad , at least the frame is guaranteed for life & it's backed up by a large franchise company, " Decathlon"
Not trying to promote anything about the Btwin, I have a list of more cons at the moment & am upgrading a lot of components to make it the way I want it.