Enlarge (credit: John Timmer)

Foldable bikes offer a pretty obvious trade-off: the convenience of something you can easily pick up and store in the corner of an office or small apartment, but with some compromises in the cycling experience. Typically, putting a greater emphasis on one of those will mean sacrificing a bit on the other.

But e-bikes offer the possibility to sidestep some of that trade-off, boosting aspects of cycling performance without adding much in the way of added bulk. And the Gocycle G4 provides an excellent demonstration of how well that formula can work out, offering excellent performance in a thoughtfully designed package that is easy to pick up and lug around. It's not so good that it will completely replace a regular bike, but it comes a lot closer than I expected, and it has a number of brilliantly designed features.

All that said, the bike still has a couple of issues that temper my enthusiasm a bit.

Enlarge (credit: John Timmer)

For many years, talking about fat-tire bikes meant you were referring to mountain bikes. But a more recent generation of bikes has dared to ask, "You call that fat?" These bikes, equipped with comically wide tires, promised to retain traction on just about any surface imaginable and to soften bumps without requiring a suspension.

Earlier this year, I had the chance to try out my first ultra-fat tire electric bike . Unfortunately, it was also my first mountain bike frame and the first folding frame I had tested. There were so many new things about the experience that it was tough to evaluate which aspects of the ride (good and bad) were due to the product and which were due to my unfamiliarity with the bike's features.

In an attempt to get a better perspective on things, I will be spending this spring riding a dedicated ultra-fat-tire e-bike, a dedicated folding e-bike, and a dedicated mountain e-bike. First up: the $1,500 Velotric Nomad 1 , which falls in the ultra-fat tire category.

Enlarge / The Vanpowers City Vanture. Spotting the "e" on this e-bike at a glance is trickier than most. (credit: Kevin Purdy)

A "city" bike could mean many different things. It could be cheap, so there's less angst when it is almost inevitably stolen. It might be simple, with fewer gears and add-ons because the commutes are short and relatively flat. Or perhaps it's a lighter bike, one more easily hauled onto a curb or up a flight of apartment or office stairs.

Vanpowers' City Vanture is cheap and light only compared to other e-bikes (fully assembled, it costs $1,750), but its belt drive, internal hub, and five-level assist make it somewhat simple. It's also limited by a lack of accessory mounts and a gearing and motor setup that makes it more difficult to start and stop often in traffic or climb steep hills. For the right kind of rider, it could be a good pick. But you'll want to look closely at the City Vanture before choosing it for your urban or trail commute.

Oh, and you can build it yourself if you want to save a few bucks. This bike is a collection of interlocking tubes held together by mortise-and-tenon construction and bolt collars. You put the tubes together, run the cables through them, bolt everything else on, and put the wheels in place. More on that in a bit.

Enlarge (credit: John Timmer)

Cyrusher offers a wide range of e-bikes , from basic around-town frames to rugged all-terrain bikes, with the unifying theme being very, very fat tires. I'd seen a number of people cruising around on extra-fat tires (as in, much fatter than a mountain bike's) and was curious about them. Just how much did the huge surface area of these tires slow down your ride? And is the traction they offer worth paying that cost in performance?

So, I was excited about getting the chance to try one out to see for myself. But then I noticed the XF690 Maxs and got excited about a bunch of other stuff, too. It was a folding bike, and I'd been wanting to try one of those. I've spent almost no time on mountain bikes and was curious about taking one across some rough terrain. The XF690 Maxs seemed to offer the chance to scratch a number of itches at once.

It didn't quite work out as I hoped, in that some of the things I wanted to try weren't especially compatible with each other. So, while the XF690 Maxs is an interesting bike, it's somewhat less than the sum of its parts, in that designs dedicated to just one of these capabilities will probably get you a better experience.

Enlarge (credit: John Timmer)

"You can let everyone know that people said it's a really nice-looking bike."

I'd never received comments like that when testing previous e-bikes, but I got compliments several times when out on the Vintage Roadster, and it's easy to see why. The bike is gorgeous, evoking classic motorcycles of a century ago, straight down to a battery shaped like a two-cylinder engine.

For me, it constantly called to mind the opening scenes of Lawrence of Arabia , which show Lawrence speeding off on one of those classic machines. Those who have seen the film know that the scenes end with his death in a motorcycle crash. This brings me to my mixed feelings about Vintage's e-bike equivalent of a supercar. I was introduced to the Vintage after I reviewed a Super73 e-bike , about which I expressed some concern over how easy it was to accelerate the bike to a very illegal (and potentially dangerous) 50 km an hour. Vintage's sales pitch for the Roadster was basically "we have one that goes even faster."