Aluminium Frame Tubing in Steel tube dimensions ???

[Lazarus]

Some of you might recall a post by me with a white aluminium framed Zues in. This bike came to me kitted with Carbon Chorus STI groupset throughout, and had Columbus tubed chrome aprebic forks fitted as genuine item. Point is : "This bike was not some cheap throw together".

Anyways, I've re-sprayed her and she looks very nice. I dumped the aprebics for a set of Alan alloy forks I acquired and it is a seriously light frame now.

Question : How come all the tubing is the same dimensions & shape as standard steel frames ie: 531/753/Columbus ?

seatpost diameter 27mm BUT external seattube takes a bog standard front mech ? (28.6 ?)

What I'm wondering is who the hell made this frame, it wasn't Zeus thats for sure, they just didn't make them as far as I can find out, not like this anyways. They (and everyone else for that matter) opted for OS tubing & / OR reshaped tubing to compensate for the aluminium being weaker than steel tubing. It looks a lot like a Cannondale frame, and the geometry is real tight, but Cannondale never shipped with chromed Columbus tubed aprebics. The bike came from Manchester area. The seller told me it was his, so a 1 owner only situation.

I'm miffed because I've only just noticed that it looks like a standard steel race frame, but it's aluminium instead ? TIG welded very neatly, but NOT cleaned off like some models. I know you'll want pics (tomorrow), but the question will revolve around the tubes being the shape & dimensions they are, as opposed to who made it (Zeus etc). Zeus is a brand name. Who made the frame ? I'm guessing 1989 at the outside, but more 1992'ish because of its design. Hope this all makes sense. Laz.

 

[Jonny69]

They look like aluminium-size tubes to me. Much fatter compared to a 531 set:

 

[Lazarus]

Hi Johnny "I know what you're saying buddy but with a 27mm internal & a 28.6mm external on the seattube, that's standard steel sizes isn't it ?. The top tube is also 28.6mm external ? I was expecting a 30.2? outer diameter on the seattube (OS frontmech bracket). Admittedly the downtube is slightly larger (normal for alu tubes) but most aluminium frames used a profiled tubing especially on the downtube, slacker geometry (greater wheel clearance).

My point is that this Aluminium frame follows steel framed rules of construction ie: geometry,tube shape, clearances. I'm also very curious because the frame was not cheap (based on the assumption that no-one would pay for a custom build with Chorus Groupset on a cheap as chips alu frame). My mind is asking " who would build such a frame ?".

If this was a simple Columbus SL / Reynolds 531-753 frame then I'd understand the frames value in context to the complete build, but being aluminium it breaks the rules. If it was badged a Zeus, but is not a Zeus (normal for many frames themselves) then who did build it ? Cannondale ? Also, why the Columbus chromed aprebic forks ? These fly in the face of what an aluminium frame was all about, weight. The forks are almost as heavy as the frame.

It's this combo of information that has got me puzzled. It even has a frame number that has nothing to do with Zeus ? Yet the frame is a genuine from scratch built badged Zues, not a re-spray re-badged Zeus. Orbea (Zeus) simply didn't make this frame, especially not with steel aprebics, not as standard anyways. It's this I'm hoping someone can prove me wrong on, ie: "confirm they have seen similar combo's on new off the shelf Alu framed bikes". I'm guessing this thing cost around the £1000+ mark when bought way back in 1992-94, so the frame must have heritage / pedigree somewhere I have asked before if anyone recognises this frame&forks but to no avail. Thought I'd try a different approach I was going to just dump the frame as a hack, but now its resprayed & I recognise it's quality, its staying in my collection instead. Later J, Laz.