Just risked it with only the front brake now that I got it to turn on... the front brake is only engaging at half strength (thankfully there's a nearby parking lot that's safe to test things at), the pedal assist takes a year and a half to engage. It just randomly powered off twice -- pretty much when I started going into deep turns -- and the overall feel of it is off since even with adjusting the derailleur (I don't like 'em, but I know how to work on them) the gears are utterly banjaxed... likely from the short chain since it seems to work better in higher gears.
The "fit" of the battery is so stiff it feels wrong almost like the cavity it goes into is too small for it (bent in shipping? that' down-tube is some thin-ass aluminum!), The buttons for the controls are too far from the hand to reach without letting go of the grip, Feels like I'm too far forward as if there's not enough rake on the fork...
My first Nakto may have died at the 20 mile mark, it's replacement may have died at the 30 mile mark, but in terms of mechanical quality they make this thing look like a rinky half-assed tinkertoy!
I can’t speak to the Aventon as I’m not familiar with the brand. However I did just order a $1500 Espin 21 Sport and so far my experience has been completely different.
The deraileur works just fine, though it needs a bit of fine adjustment.
The brakes worked fine out of the box.
The battery came 70% charged so I was able to take a test ride as soon as I got the bike put together.
Riding with pedal assist takes some getting used to, but there isn’t anything with the controller‘s start/stop behavior I strongly object to yet.
My bike has an adjustable stem so I was able to put the handlebars far enough back and high enough up to ride comfortably. That said I’ll likely replace the bars with some that rake further back like on a cruiser.
This is my first bike with a front suspension and I’ll have to say I’d just as soon skip the weight and complication if I had to do it again. On the other hand I haven’t really tried riding offroad or adjusting the pre-load on the fork yet.
In any case maybe you should buy an ebike through a dealer? This way you can test ride the bike, check how it fits you, and check mechanical quality and fit & finish before putting your money down. Also a local dealer is likely to do things like adjust the deraileur and brakes as well as charge the battery before letting the bike go out the door.
I’m not well versed in troubleshooting hydraulic brakes but it does sound like yours need to be bled.
Aventon does have a reputation for their pedal assist taking forever to engage. Check on the Aventon forum to see if you can override this with different controller settings.
I do think it is possible to get a decent ebike for > $2000, however your expectations need to be set appropriately.