Columbus Tubing

[marjude]

I have purchased a Somec frame of mid to late '80. It has been repainted so I am not certain as to the tubing type although I was told it was Columbus SL. It is a quality frame having significant chrome work like many Italian bikes. It is 54cm x 55cm in size and weighs in at a hefty 2950g (frame & fork) where as another bike I own being 53cm x 54cm and of Columbus SL weighs in at 2600g. It suggests to me that 350g is too big a difference for the first bike to be made of SL. Both have a seat tube size of 27.2 and both have the typical look of Columbus forks. What other heavier Columbus tubing takes a 27.2 seat post? I was under the impression that lower end tubing takes a smaller seat post of 26.4 or 26.8.

[koshari]

Could have been reamed?

[rkelsen]

It has been repainted so I am not certain as to the tubing type although I was told it was Columbus SL.

Perhaps that was a lie.

Buyer beware. Avoid buying anything that's been repainted.

It is a quality frame having significant chrome work like many Italian bikes.

Is it new chrome?

[marjude]

It has original chrome and in good condition. Probably the info I am after if anyone has experience or knowledge of the relationship between seat pillar size and frame tube types assuming the tube hasn't been excessively reamed.

[Clydesdale Scot]

SLX and SPX will have helical ridges on the inside bottom of the seat tube, down tube and chain stays. TSX will have the same ridges but they extend the entire length of the seat and down tubes. There will be similar ridges on the inside of the bottom of the fork's steering tube for all three tubesets. SLX and TSX use a 27.2mm seat post while SPX uses 27.2mm.

A SL or SP frame will have these ridges only in the steerer tube and require a 27.2mm or 27.0mm seat post respectively.

An SL or SP tretubi frame will use a 27.2mm or 27.0mm post but not have the ridges in the steerer.

A Cromor or Matrix frame uses a 27.2mm post size and unridged steerer but has a silver decal with a blue border.

An Aelle frame is identifieded by a 26.6mm seat post and no ridges in any of the previously mentioned areas.

Source: http://www.bikeforums.net/classic-vintage/347131-columbus-tubing.html

[marjude]

Thanks Clydesdale Scott. Just the info I was looking for. I have what appears to be a high quality frame but significantly heavier than SL that I am familiar with. This may help to narrow down the possible tubing type.