Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

I'm disappointed it doesn't (seem to) do regenerative braking... so elegant, don't waste that power, reuse it! But I don't think this is a big selling point, and you can always add it later.

I think your marketing approach is what will make or break it: "non-sweaty to dates/interviews" and the phone-charger could be the killer app (perhaps look into what segment actually experiences this pain most? Many of today's phones have adequate battery life for some people's usage; target those phones + usages that don't).



Regenerative braking often doesn't pay off. Note that you don't need a whole lot of energy to put your bike into motion, while you need quite some energy to keep it moving due to friction. Putting in numbers, if you go 5m/s=18km/h=12mph, your kinetic energy is 100kg*(5 m/s)²/2 = 1.25kJ, which at 125W can power you for ten seconds.

You can cast longer than ten seconds in front of a red light in most situations. And keep in mind that for regenerative braking to work, you must walk twice through the whole efficiency chain, which is generator -> electronics -> battery -> battery -> electronics -> motor), giving you an efficiency of about 0.85^6=37%. So 3.7 seconds.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: