Cyclocross - Picture this build...

So I want to build a cross bike, and here are the parts that I have thus far. Most of this stuff is vintage.

Wheels: one Campy Omega 32 laced to a Dura ace hub with a 7sp cluster, one Mavic MA40 laced to a matching dura ace hub, also 32 spoke

Crankset: Dura ace double with a 52 tooth biopace chainring and a 32 tooth mystery chainring

Derallieurs: Dura ace 7400 series front and rear, front is braze on

Shifters: Right now I have dura ace downtube shifters, but I'd like to find some of those old 8sp STI's

So I'm thinking about getting a crosscheck, but I'm still looking for other frames. Anyone think this could be a sick build with a funky mix of old/new stuff? Does anyone race cross with a 7speed rear end?

Running 52/32 up front is a huge drop. Try running something closer to 46/36, or standard compact (50/34)


I do have to give props for the vintage stuff. I'd like to see this in action.

there's no way a 32t chainring fits on a double d-a crank. i'd also opt for barcons over old sti's. if you can't find 7 speed ones, just run a newer one with pure friction!

i think a crosscheck would look nice setup with that group though.

That was a typo...it's a 39t chainring. I'm really torn right now though, I've been looking at period correct road racing frames on ebay..... I'm starting to really want a Miyata. But a cross bike was my next planned build. Who made a vintage (late 80's early 90's) cross frame?

I ran a 7 on my sorely abused 80s road bike for the first year I did cross. Seven speed cassettes and freewheels are available cheap. You'll basically be running it as a single chainring. You might want to replace the 52 with a guard or a 46 or 48 ring. I put a set of cheap Sora brifters on a late 80s Shimano 105 set up and it still runs great.

Can I use any 8 speed brifter (dura ace, ultegra/600, sora) with the 7400 DA deralleurs? How many people run barcons on a cross bike? I'm thinking that might get hairy in a trailriding situation, which is why I already ruled out downtube shifters.

I think the derailleurs would be fine with the 8 speed cassette. At least I knwo you can use 8 speed derailleurs with 9, and 9 with 10. It's the shifters that need to be correct to the # of gears. And chain, of course.

As to the barcons, I think they're just dandy for trail riding. Very precise shifts and you can dump a lot of gears at once. It's good to set the bike up so you're comfy int he drops though. Like shallow bar or even a flared one like the on-one midge.

Ok, but I've got a 7 speed cluster on there at the moment. And whats up with my STI lever options? I can use a Campy 8speed lever???

Here's my understanding of the Dura Ace 8 spd STI situation:

DA8 cog spacing is the same as any other shimano 8 spd cog spacing. If you have a freehub body that can take 8/9/10 spd shimano cassettes, any 8 spd cassette will work. To move a DA8 derailleur the correct amount, however, you must have DA8 shifters. Cable pull is different in the shifting mechanisms of other 8 spd STIs. Concordantly, the DA8 derailleur has a different cable pull ratio than other shimano derailleurs.

So yes, you need DA8 STI's, barends, or DT shifters if you have a DA8 derailleur and want to run 8 spd.

Ok, but I've got a 7 speed cluster on there at the moment. And whats up with my STI lever options? I can use a Campy 8speed lever???

You can use a campy 8 spd lever, if you use a shiftmate, but per the above post, the type you want works with non-DA8 spd Shimano rear derailleurs.

I've used Chorus 8 ergos to shift on shimano 8 spd cogs with a shiftmate and a 105 rear derailleur. Butter.

That was a typo...it's a 39t chainring. I'm really torn right now though, I've been looking at period correct road racing frames on ebay..... I'm starting to really want a Miyata. But a cross bike was my next planned build. Who made a vintage (late 80's early 90's) cross frame?

I think that all the Euro bike makers did. Here's a Gazelle Champion Mondial cx bike.

http://farm1.static.flickr.com/45/395660656_d1d96bcb57.jpg?v=0

Do some searching on Ebay. You might have to go to the European sites, though.

That's rad. A vintage CX bike is a long term goal for me. Caloso, when are we going to do that vintage ride?

I have done something similar with old road components. I just bought a used cross frame and hung mostly older stuff on it. I had 7 speed downtube shifters and switched them to bar end shifters using this product from Rivendell and have been very happy.
http://www.rivbike.com/products/list/shifters_and_derailers#product=17-068
only $25 for the pods and they shifting is great. I don't do any racing on it, but use it more as a commuter/touring/dirt road bike. It is my favorite bike.

That's rad. A vintage CX bike is a long term goal for me. Caloso, when are we going to do that vintage ride?

Hah! Yep. We're definitely going to have to do it.

Ok, but I've got a 7 speed cluster on there at the moment. And whats up with my STI lever options? I can use a Campy 8speed lever???

You can use any Shimano 9 speed brifter along with your current setup. The cable pull ratio of the 9 spd brifter is the same as DA8 shifters.

Apparently, Sheldon Brown's site said that 8speed DA rear derailleurs have a unique cable pull ratio. And for the rear derailleur I should only be using DA levers. Which sucks, because they are expensive.

Apparently, Sheldon Brown's site said that 8speed DA rear derailleurs have a unique cable pull ratio. And for the rear derailleur I should only be using DA levers. Which sucks, because they are expensive.

read my previous post. sheldon agrees with me if you look hard enough...