Pink Steel "Sarah Sport"

Or use a hair dryer or vancum cleaner

They definitely exist because my custom built frame has them, they're a relatively high end feature.

Yeah, had it on an old Dave Hinde that I had. Also on a Trek Edmonda.

Can confirm that one of my frames has them too

Okay interested to hear peoples thoughts re brake cable. I removed everything and shined a torch down the tubing but couldn't see much at all. An attempt with a vacuum as suggested by @billygoat8 but no change. Interestingly I tried running a gear cable down there to see if it was blocked and it ran through fine. I think the casing is 4mm as oppose to 5mm for the brake cable. I presume this rules out internal stops unless they are a ring around the circumference of the tube. As tried before I can get a brake cable in more like an inch and a half before it stops. Any thoughts?

Any thoughts?

Convert to fixed, put an aerospoke on the front. Cover the redundant top tube holes with a neon orange camouflage neoprene protector.

Ride like a cunt.

Sorted.

Always an option

The 4mm gear cable goes through rules out being blocked did you try 5mm cable in the oppoiste hole .next try fitting a 4mm cable attached to a cordless drill and clear out possible rusty in the entrance and exit there might be rust .then try again with 5mm cable.

Thanks, I think this is the right approach. I reckon theres a thin amount of rust at both entries but otherwise the outer should run the whole way through. Getting a drill out is a bit beyond my current DIY but also the answer.

Could you create some sort of capped grommet/ferrule on each end and run the cable through that way?

Maybe you have summat like this:
http://davesbikeblog.squarespace.com/blog/2010/10/12/brake-cable-tunnel.html

Great find!

This is a great link, it took a fair deal of force to have the brake cable enter so could well be meant to work like that. I'll give the entries a little clean and give it a crack with some spare cable tomorrow. Would certainly be an easy fix if this is the case.

I have my uses.

I'll have a crack at following the diagrams in @jontea 's link, otherwise this isn't a bad idea. Had initially thought a step down ferrule but I'm not sure it would sit at all flush.

Sarah Sport bikes pop up from time to time here in Belgium. They bought frames from different frame builders and put their decals on it. For example I've had one myself, which was a Flandria frame. No idea who build this frame, but it's a decent frame, 99% sure from a (unknown) Belgian frame builder.

Nice to know! Even if I can't find out the builder nice to think it's a decent frame and know where it's from. Unrelated but the 600ax project of yours is fantastic.

Thanks!

You have a nice frame there for sure. The internal brake cable tube is also something that I've seen in some frames. Nice touch...