Strobing electrodynamic cycling LEDs
I was going to go with Pedalites, a previous Cool Tool, but I didn't want in-pedal generators that add resistance to your effort. These front/rear-mounted strobe lights add very little unsprung weight to both wheels and work via magnetic induction, so there's very little additional weight and no added rolling resistance. The initial ride takes about a mile to bring the front (white) LED up to a full charge, while subsequent rides have me fully lit in about fifty feet of pedaling. The rear (red) LED gets flashing in about half the time and stays flashing longer during any stops (it also flashes more regularly). They both flash for at least two minutes after stopping, which is ideal for early AM rides and for any stopovers where you're basically waiting for traffic.
I put about 400 miles on my SL120s last season. They worked terrific. After storing my bike for four months -- no activity -- they worked perfectly again on our first ride of the 2008 season, a "Midnight Madness" run at midnight, followed by a post-ride trip to the bar. The lights recharged within half a mile (white always takes longer than the red). 6.97 miles, 35 minutes, and the red kept flashing the whole time I was in the bar (15 minutes -- we were tired!).
The caution here is they mount on your axles, so you're not flashing "high" as you might with saddle lights or a headlamp. They do not effectively illuminate the road. These are not overnight travel lights. They're safety lights, a smart pickup for any lowlight rides. A great investment for me: increased safety, no more batteries, and definitely the best "green" investment I've made for training. Short of breaking in a crash, these lights will last me decades. The LEDs are not likely to burn out for at least ten years and you can measure the magnets' lifecycles on a geological scale.
Bonus tip: The instructions stink, so you might be tempted to mount it outside the fork, because it's easier and does not involve removing the wheel (my buddy mounted his incorrectly). Don't be tempted, you cannot move the bracket close enough to the pickup magnets unless it is mounted inside the fork -- wheel has to come off. Not a big deal up front, but could be axle grease messy for the rear. Once it's on, though, you'll be within 3mm of the pickup magnets and generating nearly-free electricity.
-- Christopher Wanko
Available from Chain Reaction Cycles
Manufactured by Reelight Aps
Pedalite Bike Pedals
Self-generating LED lights for urban cycling
I have been using my Pedalites the last couple of years for short-range commuting up and down an unlit, rural county road, and would indeed recommend them, $75 price tag and all. They work just as advertised: pedal for 20 seconds, and the dynamos charge up and power flashing LEDs with a resulting effect similar to marker lights on a truck. The pedal incorporates both a white "front" and red "rear" LED. You never replace batteries. They have held up to rain, though I haven't done an extensive amount of rain riding with them.
I would say they are really best for a city commuter (I recently transplanted them onto my city bike), because the dynamos do add resistance to the system. However, I don't mind having to work a little harder for that extra light. Note: a charged set will flash for over five minutes after you finish pedaling, which means that after you chain and walk away from your bike, it's still there flashing "look at me! look at me! (steal me!)." Of course, "Look at me" is exactly what you DO want while riding. The LEDs don't emit enough light to navigate, so you still need at least a headlamp -- certainly while rural riding -- but their side flashing is especially valuable for urban riding.
-- Ben Goetter
Pedalite Bike Pedals
Available from and manufactured by Pedalite Ltd