 Silvercross is an Italian student studying mechanical engineering. Since gas is getting up to 1.80 a euro per liter ($9 a gallon!), he needed a cheap way to get to school. This lead acid battery powered bike was definitely built on a budget, but the skill and creative spark of the builder was not on short supply! Read more  He started with some components from a donor bike. Then a new frame was built on top of it. It is lengthened, reenforced, and built up to accommodate the heavy battery pack.  It's very important to keep the weight as low and centered as possible when using heavy batteries. Most people won't even touch lead because they weigh so much (among other reasons!) I remember my first ebike had 40lbs of lead in the rear rack. It was so tail heavy that everyone I let ride it ended up dropping it when they tried to get off of it. It was just so heavy and awkward to handle! What silvercross has done by putting the batteries where they are on his bike is to make what would be a very poorly handling build into something that handles just fine. Even though I wouldn't consider using lead acid on an ebike again, when done properly like on silvercross's bike, it CAN work just fine. And since lead acid is so easy to deal with the difference in price can be massive! All you need for a lead pack is $100 in batteries, a $20 charger, and some wiring. It's almost beautifully simple.  He wasn't too satisfied with the original fork, so he adapted a new one from a donor moped. This oil shock may weigh a ton and not perform as well as a $1k DH fork, but it's cheap, overbuilt, and performs much better than most OEM bicycle forks. You may have noticed some of the last few bikes I've profiled have gone this route. I hope the trend keeps up!  This is the two step transmission designed to gear down the high speed Turnigy C80-100 motor to bicycle speeds.  And here is the completed project! Very pretty for a "budget" bike! I would love to ride this thing! Here is what he has to say on how the bike is performing: at the moment it runs very well, apart from the SLA batteries, that gives me only 6Ah instead of 12Ah.I'm upgrading it with additional 7Ah SLA batteries, waiting for the budget for some serious LiFePO4.I'm
also working for a new controller/logger, it's like the cycle analyst
but it gives additional features, additional sensors and a very nice
128x64 graphic display. but time has to come.....  as
for the performances, maximum speed is set to 60km/h to reduce an
excessive battery drain, in fact at the moment I only get 20km of range
(the exact range I need, actually, but some additional batteries would
be better for sure). |
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Bike of the week >
15 - Silvercross's hand built cafe racer |