Diamant cyclocross bike

[Stempie]

Last week I drove down to Belgium to pick up a Diamant cyclocross bike. Vintage cyclocross bikes are very hard to come by, so I was really happy the one I found was in pretty good shape. I bought it off the first owner who had it made in 1985.

I plan to build it up with a SRAM Rival groupset and I also have a set of wheels with DT Swiss 240s hubs and black DT Swiss rims lined up for the build. I haven't decided on what color stem and seatpost I will go for. Black would look great, but I have a Cinelli Grammo stem and 3TTT Alutan handlebar lying around that might also be nice on the bike. Headset is going to be either a black Chris King.

As you can see tire clearance is rather minimal. Even with 32mm tires on there is barely room to spare, so I may need to dig up something more narrow.

 

[David B]

Re:

You may struggle a bit with the tyres. Older frames tended to be built for 28mm ones, as I know to my cost having owned a mid-80s CX frame myself. Panaracer Crossblaster or Schwalbe CX Pro Light are probably your best clincher options, I've used both and both are on the skinny side of a nominal 30mm, without losing anything in performance. Tufo appear not to make 28mm CX tubulars any more but you might be able to get them old stock. Challenge and other cross tubs are mostly 32+ mm these days.

David

 

[mrkawasaki]

Cool to see another - what year do you think this model is and what tubeset?

 

[Stempie]

Not sure what the tubeset is. A similar looking Diamant cx bike I bought last year was built from Ishiwata EX 4130 triple butted steel, but this one seems to be a bit older though.

 

[Stempie]

The Diamant is starting to be a real pain in the ass.

Yesterday I tried to install in the headset with a headset press. Unfortunately the press wasn't really needed, seeing as the headset just slit into place without much force. So it appears the head tube is stretched.

It didn't stop there. One of the (rusted) dropout adjuster screws broke when I tried to remove it, leaving quite a bit chunk still inside the dropout.

Finally, when I installed the wheel I noticed the fork isn't aligned properly (e.g. bent).

 

[Johnsqual]

Re:

Oh bummer

I love a good old steel cyclocross, but it's always a bit of a gamble considering the abuse such frames got put through. My own list of cyclcocross fails includes:

- Discovered a hairline crack in a chainstay
- Bent top and downtube, presumably from a front end crash
- Cantilever stud came loose
- Same loose headset problem as yours
- Bad cable routing cut through brake cable, causing an embarassing crash
- Stick got caught in spokes and derailleur, causing derailleur to go into spokes and breaking derailleur hanger
- Found series of cracks in high flange hub on a rear wheel

For the headset, I guess the options are either threadlock (if it's not too badly stretched), a shim to fill the gap, or tapping dents into the headset round the interface with the head tube to get it to fit (but I guess you'd want to use a different headset than the Chris King one for that last one!).

Is it possible to re-align a fork like that? Or is it too dangerous to start re-bending an already bent fork?

Johnny