I wanted to buy FRM CU2-Al ISIS bottom bracket, it is very light only 135g and it is with ISIS standart, perfekt match for my requirements, but the spindle is made from 7075 Alloy, what made me doubtful. As far as I know nobody jet hasn't used an alloy to make bottom bracket spindle.

What are your opinions? Is it safe, is it recomended to risk?
Does anyone knows anything about those bottom brackets?

P.S My weight is 75kg.

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Light weight everything!

A manufacturer making BB spindles from Aluminium is nonserious in my eyes.

American Classic ISIS BB weighs 140 grams and it has a steel axle.
They are not in stock but they should be here by 1 March.
www.amclassic.com

biketuna

Cannondale made a BB axel in aluminium, on their Coda Magic 900 crankset. And yes, I have seen one that had bend.

Thanks guys!
I found that there is no real proof that Alu bottom bracket is very bad, ok I admit that it is much less stronger than for example American clasics bb, but as I didn't get enough information, I will just have to buy it and test by my self.

Thank you all!

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Light weight everything!

Let us know how it works !!

Al BB is a new development, but the larger diameter of the ISIS axle makes the use of al possible. The problem is we've had skinny taper axles for so long, where al wouldn't be strong enough. Also the ISIS interface spreads the load better than taper.
That said, Crank bros, am classic do light Ti and cromo ISIS BBs which will last longer if you decide to undo the crank bolts or throw things at it etc...