When bad things happen to good builders
BY RADICAL BRAD, ATOMICZOMBIE.COM
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Wheel dropouts broke off of an electric hub motor, causing a dramatic crash. |
"Perhaps this one was only partly Murphy's Law fault, leaving the other
half of the blame to the crazy dude that didn't listen to reason. When I
was building the
E-Style Electric BMX,
I originally put on a pair of front suspension forks from a mountain
bike. Now, this might not seem like a bad idea, but if you know a little
about electric front hub motors, then you
probably know that this is a recipe for a face plant.
Here is the
problem in brief. Front suspension forks have aluminum dropouts.
Aluminum is an evil unpredictable metal. Front hub
motors introduce heavy torque to the axle. The axle is connected to the
dropouts. Eventually, the aluminum dropouts rip away from the fork tubes
and you get a very rude and swift
introduction to the pavement. Sadly, I knew this ahead of time.
I never intended to release the plan with these forks, but
didn't actually think that such a well-made set of forks would be an
issue, so I threw them on for some test riding one
weekend. My hub motor was only rated at 500 watts, but I did modify the
controller and bump up the voltage from 36 volts to 48 volts, boosting
the top speed from about 25 Mph to 40 Mph
or better!
There I was smoking down a street in my neighborhood and I
took a sharp turn into the parking lot of the coffee shop I like to
visit, trying to look cool as I carved into
the lot running under silent electric power. Actually, I did look cool
until the exact instant that the front wheel went in a different
direction than the rest of the bike!"
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