Which lightweight aluminium frame?

I will look at Rose and Canyon as well for good alu frames.

Have you looked at Hunt? Latest review seems very good and it does look very good.

Nice.

Would be interesting to see how it rides.

Keep updating!

Try c-bear for the bracket as they seem to have multiple BB options for numerous different shells & chainset combinations. Just about to order one for my narrow S-Works BB shell so that I don't have to run numerous spacers with a Rotor chainset.

I got a Aithein in Jan to race on, my usual bike is a '12(bought in '13) BMC RM01... and the bloody thing has been hung in the rack for the last 5months. the Aithien is the same geometry, and the both have the exact the same kit on bar the seatpost(ultegra 11 alloy bars/stem). wegihs a smidge more than 7kgs (mine is a 53 and its 7.05kgs with some swiss side wheels)
I've had just about anything (apart from a pinarello, they just don't fit me) under the sun... Cervelo, cannondale, principia, colnago, Lemond, trek, bianchi, litespeed, giant, specialized, guernecotti, etc, etc . I can honestly say that the Aithien isn't the stiffest bike I've ever ridden, it's not harsh,& it's smoother on a rough descent with the right wheels than the bmc, that's supposed to be one of the blingest things on the planet and to boot it's cheap!
so it's not on most peoples want list but it's up there with the best bikes I have ridden.
bottom line: if you want something smooth & flexy, perhaps look elsewhere. if you want to feel what's happening underneath you then try one (btw it also seems to love being abused..) got in some 7hr rides on mine and have a bunch of Strava KOM's on it, and not felt as beaten up as on the BMC.

hope it helps!

Tbh I don't think I'd say it was really harsh, personally I couldn't really see any difference between the kinesis and a decent carbon frame. But then again I just ride, I'm no expert.

As for the weight, when I was building it the weight weenie really come out of me. I weighed each part before putting it on and then weighed the bike at the end - Just a shade under 7kg without the pedals. That's with the Chorus set up but Athena carbon chainset (640g). Wheels are Campag Zonda's and finishing kit is mainly Deda. I really ought to get a pic on here, it's a beautiful beast. In orange as well

I would defo second the Kinesis Aithein, got one myself in February and stuck a Campag Chorus groupset on it. Truly amazing bike

Before I chose the Aithein I was looking at the Isaac Graviton - beautiful looking bike but they didn't do frame only...

Bowman palace? Canyon also do some nice alu frames.

Definitely look at both of those, I tried an Aithein recently and it was VERY nice. Look at Rose and Canyon too, the Germans aren't as hung up on carbon as we are so make some nice light frames.