The business model is selling a dream, and VCs know it, and they don't mind, on the off chance that a company takes off. And that's the whole Indiegogo model. Your listed prices seem great but reasonable, but that's very far from $1000 for a $5000 ebike.
Reminds me of this quote.
The reason why there are so many Chinese re-branded E-bikes in the US market is that the cost of doing things right is prohibitive and people always shop for the lowest-priced item. At least in the <$2K category.
Still, the barrier to entry to the E-bike market is WAY lower than the car industry. To be able to build a great electric car on a small scale, one needs at least $4-5 billion.
But, RadPower can grow from $320K Indigogo to a fairly sustainable business at $30M+, then it proves thing that, if you are shrewd enough, do aggressive marketing, it is possible to put 50K bikes on the market.
Again, the barrier to entry is low but the next 3-4 years will see tremendous growth and reorganization in this space.