kraftwerk 

My friend has carbon bars ~ carbon laid over a thin aluminum handle-bar, together they work to make a solid lightweight mechanically-safe handle bar.
I have heard similar things about forks. Another guy says his carbon forks are just 'wrapped' in a carbon layer but are 'really only aluminum'
In that case too, I am pretty sure the carbon is structural, a thin layer of carbon fiber over an aluminum fork. Whats the story with this method of construction?
Is it common & safe? The forks, when I got to see them in person, were not much lighter than a conventional fork. What gives?

base2 

Things aren't done that way much any more. To a large degree, I think the carbon over x had a lot to do with manufacturer production learning process. All the strength expected but able to offload some stress to a "stronger" and "lighter" material. I sort of always considered carbon bonded over aluminum to be an intermediary step in bike part evolution.

I have a bar, stem, & seat post so constructed as a gift from some random guy on craigslist. I think the biggest benefit is the combined different materials create some perceived safety factor. Not that all things are all marketing...But grams are grams. They are lighter than the big name, high quality aluminum equivalent. I'll give them that. But not lighter than a recent quality full carbon part.

IOW: There probably isn't much to school you on.

Andrew R Stewart 

My understanding about carbon wrapped tubes (be they bars or blades) is that it's about the need to compress the fiber/epoxy with an external vacuum bag, and not an internal bladder in a costly two part mold. I'll add that most of the top layers in fiber frames are the cosmetic/scuff layer and not intended to be of structural benefit. There was a time when a fiber weave frame finish would add many $ to the perceived value, regardless of what was under that top layer. Andy

Camilo

I have a Ritchey aluminum stem wrapped in woven CF. I've always considered the CF wrap to be cosmetic. I have no idea if it's lighter and/or stronger than a similar era Ritchey aluminum (e.g. WCS) stem.

Trakhak

That's what I was told by the area Raleigh USA rep when they came out with a Technium mountain bike whose main triangle consisted of carbon fiber-wrapped aluminum tubes. Wrapping on a cosmetic layer of carbon fiber added very little to the cost of construction while requiring no additional R&D investment.

nomadmax 

galvanic corrosion

Andrew R Stewart 

Carbon can and does react with Al. So any wrapping should see the same insulation between the wrap and the inside tube that a carbon tube needs in a Al socket. Andy

kraftwerk 

I learned something... Thanks Bikeforum braintrust!