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You're not still struggling up the hills with those heavy steel bolts on your bike, are you?...

The bolts on your bike. They're made from what? Heavy, old fashioned metal? They're holding you back. What you need is some sleek new Carbon bolts, like these ones available from Poshbikes.

"You may have heard of 'Carbon PEEK', which has been used in many F1 and fighter Aircraft applications," says their website. We hadn't, but anyway these screws are produced by a similar process, CFM PEEK. Not wishing to blind you with science, but "The Polyaryletheretherketone (PEEK) materials are semi-crystalline, high purity polymers comprising of repeating monomers of two ether groups and a ketone group," according to the very helpful British Plastics Federation website.

CFM, as you all know of course, stands for Composite Flow Moulding, and we learned all about that at the very helpful Plastics Technology website. It's a wonderful thing is the internet. CFM has two advantages: it allows you to pack a lot of Carbon Fibre into the component, and you can do clever stuff with the orientation of the individual fibres.

For these screws, there's an external layer of radial fibres in a helix to give structural integrity to the thread, and through the middle the fibres are unidirection for better strength under tension. The resulting screw has a claimed yield strength greater than that of a steel screw. Poshbikes are hedging their bets for now though, suggesting that you might want to use them in applications where Aluminium bolts are permitted.

They're currently available in a limited range of sizes in M5 and M6 threads, and they weigh between 0.7 and 1.3g each. Prices are £36 for a pack of four M5 bolts and £44 for four M6-threaded bolts.

www.poshbikes.com

Dave is a founding father of road.cc and responsible for kicking the server when it breaks. In a previous life he was a graphic designer but he's also a three-time Mountain Bike Bog Snorkelling world champion, and remains unbeaten through the bog. Dave rides all sorts of bikes but tends to prefer metal ones. He's getting old is why.

11 comments

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yocto [20 posts] 3 years ago
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Good article. Made me laugh  21

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Ducci [86 posts] 3 years ago
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I'm sorry, but for full weight weenie satisfaction you need to include the 0.00000th of a gram weight savings over the portly aluminium versions  3

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Cervelo12 [77 posts] 3 years ago
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i emailed posh bikes once, i got a reply 4 months later.

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notfastenough [3661 posts] 3 years ago
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I use M5 in the walls at home, perhaps I should make my house a few grams lighter.

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Chris [142 posts] 3 years ago
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Cervelo12 wrote:

i emailed posh bikes once, i got a reply 4 months later.

I phoned Posh Bikes once, I got off the phone 4 months later.
Very good a talking, they are.

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mad_scot_rider [581 posts] 3 years ago
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Quote:

£36 for a pack of four M5 bolts

Oh is that all? I'll take 2 dozen  10

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John G [53 posts] 3 years ago
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Carbon bolts? - must be nuts.

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russyparkin [570 posts] 3 years ago
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carbon bolts, er that will be a no for me.

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Andywoo [22 posts] 3 years ago
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I've cut my finger and toe nails and removed all unnecessary belly button fluff. That should see me about even

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stealth [254 posts] 3 years ago
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why isn't everything just glued???

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yenrod [106 posts] 3 years ago
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Do dee do any f'me acamacca valve?