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I always liked the look of the Cannondale Headsite, shame it never went into mass-production.
Now someone else has had a crack at it with the [url= http://www.kickstarter.com/projects/1266057078/stemlite-integrated-bicycle-light?ref=category ]stemlite[/url]
Nice idea, badly excuted I think.
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Surely dynamo power makes more sense?
Didn't Hope used to do something similar too?
Na "trout" did once
I'm not sold on the idea, it has too many issues.
How would you charge the light if the cells were integrated? Remove the stem or removable cells - either way it's a faff. If you had a separate battery pack then why not just get a standalone light head as it's more flexible as you can switch from bike to bike.
Plus the cables are likely to throw weird shadows down the trail.
Hope did a face plate for the stem that had a mounting for their lights. Looked great with the light fitted, horrible without!!
I've always thought about it, nice & compact, ideal space in the hollow stem tube to fit batteries, but the heat/cool cycles that would be produced did concern me in relation to bolt tightness reducing over time.
Trout came up with this design a few years back & more than one LED would take care of any shadows cast by the cables.
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I do like the look of that Trout one.
I can see them selling well on commuter bikes, especially with a dyno-hub. Good from a security point of view too.
Road bike with concealed cables, and either dyno hub or battery in the stem would look good too.
On an MTB, with very varriable stem angle (fork length, tyres etc) surely having a fixed angle between the light cone and the stem means it must be very dificult to get the height right? Most bar lamps can be twisted around the bar as necessary etc.
If security and neatness is important I'd rather have one that mounted via a slim headset spacer fitting, like those bottle opener headset spacers.