We're used to handling e-bikes that weigh 20kg and more here at ebiketips, but not every assisted bike out there is so weighty. If you're after something feather-light that'll still give you a bit of a shove then how about this: the Steinbach Sonnblick. In the high-end build shown here it weighs from just 8.5kg and will cost you a pant-wetting €12,150, just north of ten grand at today's rates.
"The Sonnblick E-Assist is the lightest production electric racing bike ever built", say Steinbach on their website. "The hand-made carbon frame encases an almost invisible drive module. The Sonnblick E-Assist glides over the asphalt. It's sporty, agile and almost weightless: so light that you almost forget to use the electric motor. The drive is available at any time and without resistance for 1000 meters of climbing, or 100 minutes."
What's the drive unit? Well, Steinbach don't say but we'd be surprised if it wasn't the Vivax Assist motor, or at least something like it. That system sits in the down tube and directly drives the crank axle, which looks like what's happening here. Vivax gives you an extra 100W of power when you're pedalling at 90rpm, so it's a much more gentle assistance than a full-spec e-bike. We've tried the Vivax though and it's certainly a useful extra help when the legs are getting tired. It's friction-free, so if the motor isn't running you're basically riding an 8.5kg full-carbon road bike, which isn't exactly a hardship. The video below shows the operation of the motor via a hidden button in the bike's brake lever.
Most builds including a down tube motor come in at around 10kg but this is a pretty special bike. Shimano Dura Ace is the top-tier Shimano groupset and pretty light. The Lighweight Meilenstein wheels are over £4,000 on their own. If you're not the highest of high fliers there's an Ultegra build for a somewhat more reasonable €6,990 (£5,900) or you can just have the frameset with motor and cranks fitted for €5,300 (£4,500) if you want to build it up yourself with bits from the shed.
Who's it for? It's "the ideal road bike for professionals and ambitious amateurs who are keen to tackle particularly long and steep routes or to compensate for differences in performance within the group", according to Steinbach. We're not sure it's really suitable for professionals, unless they're on a day off, and you'll need to add the qualifier "highly-paid" to all of that, but if you fancy what must be one of, if not the lightest e-bikes out there then at least you now know where to go.
