Bianchi Specialissima X4 - what's 14mm between friends?

[Specialeyes]

Back in this thread, I mentioned that I was going to switch my Bianchi X4 to Campagnolo C-Record from Shimano Dura-Ace. I'm not a die-hard 'you-must-have-Campagnolo-on-an-Italian-thoroughbred' chap usually, but this one, like David Ginola's hair, was worth it.

Well, it got complicated to the point I began to question the wisdom of the switch and contemplated refitting the Japanese groupset.

When I stripped and began assembling the Campag components, I discovered that the Shimano headset design is 14mm neater than the Italian one. This meant that the steerer tube was cut 14mm too short for the headset top nut to engage the threads: 172mm of tube vs 186mm of headset.

I pondered for a while over the wisdom of 'cutting and shutting' such a critical component: what would happen if it gave out at speed? etc. Then, finally decided that the rest of the bike is held together in exactly the same way, so why should it.

So, I took the bits to a local frame repairer and restorer (Tim at Gunn & Co.) who fabricated a beautiful extension plug, fractionally tapered and a snug fit for the centre of the tube. It's one of those jobs that once the tube is cut, you just have to press on, no turning back!

He firstly dry-fitted it in an alignment jig then soldered it into the middle of the tube...

and finished the whole thing beautifully!

So I could then rebuild the bike in Campagnolo mode. First time I've ever set up Delta Brakes and you know what? They weren't too much of a faff, and work surprisingly well, considering how much folks describe them as the pinnacle of form over function.

So, when the weather turns crap for the next month and we have nothing but cold wet weekends, you can blame me and my new summer bike!

 

[winjim]

That's lovely.

 

[JhnBssll]

Looks fabulous. Top work!

 

[Colin Grigson]

Gorgeous

 

[dan_bo]

Top bike- proper workmanship!

 

[rogerzilla]

I've had a couple of steerers replaced over the years. This only makes sense when the fork is being repainted anyway, as it will most definitely burn the existing paint to a cinder.

14mm is a surprisingly big difference between headsets. Often there is less than 2mm needed, and that can be grabbed by facing the head tube a lot.

 

[fossyant]

Lovely, and has the right groupset on it. Can I have your Dura Ace for a couple of turnips ?

DA headsets are really low stack. Same across many Shimano TBH - My STX on my MTB is really low too.

 

[IanSmithCSE]

Good afternoon,

What would worry me about cutting an expensive set of forks would be that the steerer might be butted in clever ways.

I know that Reynolds did do a single butted steerer which was 2.2mm where it joined the fork blades/crown and was 1.6mm the rest of the way, 1.6mm was apparently enough to allow for the headset thread to be cut in.

As far as I know a double butted steerer is quite rare as the length of the steerer is so variable that double butting to allow for cutting the threads would require a large stock of steerers. Not only that but the weight saving is going to be tiny, say 0.8m off the tube walls for perhaps 3 inches.

But the frame of a Dura-Ace equipped bike might just have done this as a "show off" feature.

If that steerer were cut in the middle of the thinnest section, say 0.8mm, it may no be joinable and I can't imagine finding information on the steerer would be easy and accurate.

Looking at your photo the steerer seems to be a nice thickness and perfectly safe to weld/braze.

Bye

Ian

 

[AndyRM]

That is an absolutely wonderful looking bicycle.

 

[Specialeyes]

Thanks all - I must admit I was a bit worried about the wall thickness and whether the tube was ever-so-slightly tapered in the middle. It's difficult to gauge thickness through the fork crown so in the end we just went for it. The plug was machined on a lathe anyway, so could be adjusted for any taper - though I must admit I spent a few minutes each evening for a few days searching eBay for 'X4 fork', just in case!

 

[rogerzilla]

I had the same problem last year with an Eddy Merckx fork. Could find loads of forks, but nothing long enough for a 59cm frame. So I bought one anyway and it had an SLX steerer (very distinctive internal rifling). And a Greek guy on eBay had NOS 280mm SLX steerer tubes!

The only problem then was that all the threads had to be cut off, as 280mm is far too long for the frame. So Argos threaded it from scratch (I have actually done that myself before, since I have a die, and it's quite satisfying, but I would never do it on a freshly painted fork!)

Anyway, that lot was about £100 plus the cost of the fork and steerer, and before paint Eek.

 

[TheDoctor]

Chuff me, that's properly nice.
When I get round to restoring my 531ST, it'll be in Celeste.
And possibly have retro Campag stuff on, if I can find any at a sensible price.