i've got a Strurmey Archer X-FDD dynohub/drumbrake set-up on my front wheel, and i'm working out a lighting system for it that will work with the higher speeds a motored bike provides.
first off, some notes on the hub itself...
the drum brake usually takes a little while to break in before it stops really nice. it's mostly a matter of the brake shoes seating in place. i figure riding along and pulling the brake lever slightly, causing some drag will help speed this up.
the finish and quality of the hub is excellent, and comes in 70mm and 90mm sizes, and is priced around 60-70 bucks.
it's drilled for 13-14g spokes, but it's easy enough to drill through the aluminum flanges to use bigger spokes. i'm running 11g spokes on a worksman 26" rim.
i talked to a rep who told me the hub can be run in either direction, as in, which side the brake arm is on, and from my experience, seems to be correct. i've run it both ways, so depending on where your lights go, or where your cables route, you can set it up to look clean.
the hub is a 6v, 3w AC power supply, and is usually fine for pedaling, but higher speeds increase the voltage and burn out lights. if running a headlight and a taillight, if one bulb burns out, the other will soon after, as the voltage is then directed to it.
other problems are:
when stopped, the lights go out unless a capacitor is used to store the voltage up. "standlights" are available, but expensive. there are a number of DIY methods i've found on the web.
another problem, or maybe just an irritation (for me and the guy who has to drive towards me, anyway,) is the flickering that LED lights make. if you use extra bright ones, it's a strobe light effect that goes away as you go faster, but if you're pedaling slow or pushing your bike, it's really annoying. regular bulbs don't flicker, but don't provide the brightness of LEDs.
the real problem is the voltage output of the hub.
rigging a voltmeter to the hub and taking a cruise, i found the voltage ranging (approximately) from 5-12v at pedaling to slow motor speeds, 18-24v at cruising speeds (approx 20-25mph) and maxed out at 52v at WOT (approx 45-50mph.)
yesterday, i had a 12v, 4w headlight only set up which worked fine all day, but blew out after i took it out at night to see how well it lit up. (unless a switch is added, the light stays on all the time the bike is moving, like mine was.) i'd say i got a total of 3 hours outta that bulb.
i had an LED in it, and that lasted 20 minutes.
wiring more lights in sequence (headlight, taillight, marker lights) will help to distribute the voltage, but at 50+ volts, nothing is gonna last too long without bridge rectifiers and other stuff wired in.
so that's the start of this thread. i'm hoping to make a functional lighting system without the use of batteries (or the sometimes it works sometimes it doesn't "white wire") that can be functional, reliable, easy to make, and above all, cheap.
if anyone has any experience with these hubs, fell free to chime in. i know Barely Awake has one that seems to work fine...
first off, some notes on the hub itself...
the drum brake usually takes a little while to break in before it stops really nice. it's mostly a matter of the brake shoes seating in place. i figure riding along and pulling the brake lever slightly, causing some drag will help speed this up.
the finish and quality of the hub is excellent, and comes in 70mm and 90mm sizes, and is priced around 60-70 bucks.
it's drilled for 13-14g spokes, but it's easy enough to drill through the aluminum flanges to use bigger spokes. i'm running 11g spokes on a worksman 26" rim.
i talked to a rep who told me the hub can be run in either direction, as in, which side the brake arm is on, and from my experience, seems to be correct. i've run it both ways, so depending on where your lights go, or where your cables route, you can set it up to look clean.
the hub is a 6v, 3w AC power supply, and is usually fine for pedaling, but higher speeds increase the voltage and burn out lights. if running a headlight and a taillight, if one bulb burns out, the other will soon after, as the voltage is then directed to it.
other problems are:
when stopped, the lights go out unless a capacitor is used to store the voltage up. "standlights" are available, but expensive. there are a number of DIY methods i've found on the web.
another problem, or maybe just an irritation (for me and the guy who has to drive towards me, anyway,) is the flickering that LED lights make. if you use extra bright ones, it's a strobe light effect that goes away as you go faster, but if you're pedaling slow or pushing your bike, it's really annoying. regular bulbs don't flicker, but don't provide the brightness of LEDs.
the real problem is the voltage output of the hub.
rigging a voltmeter to the hub and taking a cruise, i found the voltage ranging (approximately) from 5-12v at pedaling to slow motor speeds, 18-24v at cruising speeds (approx 20-25mph) and maxed out at 52v at WOT (approx 45-50mph.)
yesterday, i had a 12v, 4w headlight only set up which worked fine all day, but blew out after i took it out at night to see how well it lit up. (unless a switch is added, the light stays on all the time the bike is moving, like mine was.) i'd say i got a total of 3 hours outta that bulb.
i had an LED in it, and that lasted 20 minutes.
wiring more lights in sequence (headlight, taillight, marker lights) will help to distribute the voltage, but at 50+ volts, nothing is gonna last too long without bridge rectifiers and other stuff wired in.
so that's the start of this thread. i'm hoping to make a functional lighting system without the use of batteries (or the sometimes it works sometimes it doesn't "white wire") that can be functional, reliable, easy to make, and above all, cheap.
if anyone has any experience with these hubs, fell free to chime in. i know Barely Awake has one that seems to work fine...
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