They play analogous role to cable releases on most bikes, e.g., those with V-brakes. They allow you to temporarily shorten the cable housing so that you can spread the brake pads farther apart and pull out or push in the wheel without deflating tires. They are so useful that, after living with them for a while, you ponder how you could lived without them before.

thanks for the info, if you find the tern spare let me know, interested for a lightweight solution :-)

In the case of the BYB the cable adjustment gizmo is not used when a wheel is removed but between the folded and unfolded states.

Is there something about the BYB's fold that affects a brake cable to where the brake drags on a wheel in the folded state?

+1. That's why I asked because the video didn't explain how it was used when folding the bike.

Can that Shimano or alternative be used on a Brompton?

It's a (small) pain to have to deflate the tires when I get a flat.

Sure, I have two of the Shimano ones on my Brompton. I even used them today when swapping tires for the studded ones :D. As to their use on BYB, I have no clue.

BYB seems over complex compared to Pacific iF Move - with same 20 inch wheels, roll when folded, belt drive options, one sided wheel mount (easy tire change) and faster fold ... or am I missing something ?

Tern BYB rack and pannier problems
 

I'm also perplexed about the lack of an actual platform on the rear rack of the BYB, but how could one be mounted?

Which "eyelets" do you refer to here? I would like to be able to mount panniers on this bike but there's no way of folding it with a pannier on either side and the one I can mount on the left side hangs way back and drags on the ground when I'm trollying the bike. Also no way of mounting the pop-cover to the frame even uf just one pannier is used because it blocks the frame locking bolt if mounted on the right.

Real screwey and I'm feeling so frustrated.

Suggestions?

QUOTE=tomtomtom123;21096328]The rear rack design is a bit strange on the BYB. It's offset to the right side. Not sure why. Only thing I could thing of is that it's because it has "low rider" rails instead of a full flat top rack, so the right pannier needs to be pushed further outward to clear the derailleur. And not having a full flat top rack means that you can't carry boxes or anything bulky. Although the frame appears to have extra eyelets so that you can mount your own rack.[/QUOTE]

Why would you want to fold it with panniers attached? I don't think you can fold any bags with panniers attached, not even Brompton. You can attach two panniers, just will need to choose ones suiting rear rack. You can also install front rack or front KLICKfix adaptor (either or). KLICKfix can accommodate different bags compatible with KLICKfix but max weight is 7kg. Front rack is also very useful and doesn't affect the fold.

Yes, I'm fully aware I'm answering an 11-month-old question.

The BYB does have a relatively complicated fold.

The BYB is some 16cm/6.3in smaller in its greatest folded dimension vs the iF Move.

Hmm. Bigfish, Dahon D-Zero, Dahon Nuwave, Jango Flik, Whippet...DiBlasi Avia, LePetit Bi...

I'd love to see some pics of these bikes folded with two pannier bags on the rear rack.