estebe

Gentlemen,

I have this VanTuyl frame with asymetric columbus tubing and it1's not MS due to 27.2 seat post size... The frame is brazed except for the seat tube where is lugged. Except the head tube and seat tube no tube is round:

- top tube is kind of lemon shaped as in it is a flatened oval
- down tube is a like a reversed triangle facing towards the ground
- the chain stays are different from each other , the left one having a straight side facing inwards.
I took some pictures but it' s hard to fotograph. Hope someone could help me out. Thank you

Spaghetti Legs 

I had a Coppi frame once in Columbus Genius that had a rounded corner elongated triangular down tube. I'm pretty sure it was a 27.2 post.

estebe

Nice frame, however mine is facing with the sharp part downwards...

Spaghetti Legs 

Yeah I didn’t think it was quite a match but food for thought. I think the tubing can be/ was formed into different shapes for different builders. My wife has a Tommasini Tecno in Genius with tubes shaped differently than this Coppi.

estebe

Oh well, fork decals look like SL, right? Might be that frame is custom drawn SL as well...

It's kind of frustrating really because it fits the description of Columbus multi shape tubing almost perfectly with the exception of the seat tube, seat post diameter: (found on the web)

unworthy1

Beside that one fork blade decal (and did you check the steerer base for rifling) what evidence that this is all Columbus tubing? If it's something "custom-blended" it could involve other brands as well as models of tubing, within one frame. OP says the seat tube (assuming that's the seat cluster?) is the only "lug" in a lugless frame...can we see a pic of it?

estebe

I'll take pics shortly. Yes, I meant the seatcluster . Good questions really, I'll have to check again but I don't remeber any rifling as in slx ( if that's what you mean) . Besides the columbus dropouts there is no evidence for the frame tubing, more to the point, the frame has veen repainted once as it has a Varnished by Carlos Dosoventa sticker...

unworthy1

I did not know Dosenna also did repaints, but his shop sure was active with a LOT of very distinctive and fancy "factory paint jobs" BITD, if there's 'rifling' in the steerer's base (and it's the 6 low-profile spirals type and not something from Tange or Ishiwata) it means that steerer and presumedly the fork could be SL/SP or onward/upward, including SLX, TSX, etc. The spiraling IN the bases of the main tubes (look into the BB shell) would be SLX, etc., SL and SP will have none there.

estebe

Ok, so here`s the pic with the seat cluster lug.... I have checked the steerer and there is indeed rifling (seems like vertical stripes to me), however i could not check inside the seat tube since the hole is too small to insert my finger... So?

unworthy1

Hmm, interesting: the paint certainly looks like something Dosenno would do, and the stay cap is remeniscent of Colnago, but I wouldn't take any conclusions from that! Looks like it could be from late 80's so the right era for SLX, but also right for much other tubing too...I have no more theorizing to inflict on you!

estebe

Thank you for taking the time. Maybe someone else has insight...

estebe

Anyone?

estebe

Just to bring this to the top of the list, what does the collective mind think, which is more realistic: custom drawn SL / SLX and that's it OR given that with the exeption of the seat tube fits the description of Multi shape perfectly it' rather a modified MS? Which sounds more reasonable?

T-Mar

It's really hard to get an appreciation for the tube shapes without seeing the frame in person. Columbus started offering optional tube sections in the mid-1990s. The dowtube sounds like it could be a Megatube option but installed upside down. There were obround chain stay options that would have provided a flat inside and outside surface. However, the really perplexing shape is the top tube. I can't recall seeing anything lemon shaped with a definite crease along the sides. To this end, I'm tempted to say it's a modified tubeset. Given the oversize tubes and lugless construction, I'd place the oversize versions of Thron and Brain at the top of my list and that's assuming it is Columbus to match the fork decal. I wouldn't rule out a modified Dedacciai or Oria tubeset, as both were popular during the apparent era.

estebe

Thank tou very much for answering, it' s kind of frustrating that such a distinctive set of tubes remains unidentified...one tube away from MS...

unworthy1

Just because it jogged a long-lost memory: I bought and built a frame for a friend way back 10 or 15 years ago that also had "shaped" tubes (but was none were grossly oversized) and tho it had no markings (but some strong similarities to the OP's frame) it was sold as a Diamant (maybe Belgian) and supposedly built of Mannesmann tubing. YMMV

estebe

Thank you for the info. O guesd when i'll come around to repainting it I'll just leave out the tubing d

estebe

Thank you for the info. O guesd when i'll come around to repainting it I'll just leave out the tubing decals... At leat i know that the fork is columbus (slx probably due to internal rifling)...

Nessism

Most likely MS with one tube substitution. The stock MS seat tube took an odd sized seat post (25.0?) so substituting a more normal tube makes perfect sense.

estebe

To anyone finding this through google search and for further reference it seems that the tubing is Columbus AIR (non aero seat tube version) with SLX (factory) original forks. I long last managed to find an identical frame on the internets, so mystery solved. ..

T-Mar

If it is Columbus Air, it has been further massaged. I don't recall Air having asymmetrical chain stays and it definitely didn't have creases in the top tube. As for SLX, there were no SLX fork blades. The only tubes unique to SLX were the down tube, seat tube and chain stays, which had helical ridges at the BB end. Everything else was from the SL set. That pictured fork decal is 1988+, at which time the blades included in a SLX set would have used a decal with a red border.

estebe

Thank you for the fork correction, didn't know that... As for the reference frame here it is(unfortunately missing paint and decals)