It will be interesting to see if there is a market for smaller size electric motorcycles
There isn't - at least not without a huge marketing push and dealer base.
Brammo tried with the 3.2 kWh Enertia in 2009. I don't think they had much of a euro push, and it was quite a bit less powerful. Pricing would have been around 8000 euros if released in europe.
Brammo tried again in 2013 with the 6.2 kWh Enertia Plus. This time they had a bit more of a euro push, and they sold a few bikes. Still less powerful than the Volta and still no storage, but double the capacity and around the same price.
Zero tried with the 2.5 kWh XU in 2013. I recall it being priced around 8000 euros. No storage, and a little less powerful / capacity. They discontinued the XU model a year later.
I don't think a market exists for a small electric bike priced at $8000 or the euro equivalent.
There's a saying, which I'm going to butcher: "bad products don't exist, only bad prices."
There's a market for these small bikes. Low weight, low range and performance requirements. This market is served now by 50-125cc gas scooters, which are great for urban riding at a cost of $3000-4000 (or euro equivalent). Generally speaking, these bikes are fuel efficient enough and are driven so few miles that fuel cost is negligible. Maintenance cost is not insignificant, but these scooters I suspect are ridden into the ground and then scrapped for another second-hand model every ~5 years.
There's another market for large bikes, and this is clearly what Zero is pivoting towards. Good street performance, useful highway commuting range and enough backroad range to do some reasonable pleasure rides. This market is less price sensitive and more prevalent in the US.
As mentioned above, both Brammo and Zero have tilted at the high-price small-bike market and withdrew bloodied. Chinese manufacturers selling questionable quality lead acid electrics are the only manufacturers that are successfully selling small electrics, and they're doing so by offering products at inexpensive prices. Various other manufacturers have essentially rebranded these small electrics and given them a coat of lipstick. None have really made it to market.
Last year, Yamaha discussed bringing the PES1 and PED1 small bikes to market. I suspect these could be sold at close to the $3000-4000 scooter price point if the concept-only bits are dropped and they are manufactured in volume (10k units/year). Yamaha hasn't announced anything since April, or any real specifications or pricing. So we'll see what they do.
Gogoro has made noise recently about targeting the urban scooter market in select cities, along with rolling out rental battery charging stations. It's an interesting approach with a lot of potential, but I hope their investors have deep pockets and very patient.
But Volta? Best of luck, but I don't see them succeeding where others have failed.