Having acquired a 58cm (23" in proper money) Bianchi Proto frame, c. 1990 in Columbus Max tubing, I have found that sourcing a fork with the correct 'crown' profile (I put the word in inverted commas as it should have no discernible separate part) from anywhere.
I do have my wife's bananas mates in Italy on the case but they have, thus far, drawn a blank.
I realise that this may be the wrong forum as I am in the UK and need to keep costs down as, because of traumatic brain injury, my income is very limited (yeah, yeah. Sob, sob. Bleedin' cripples).
Should anybody have any leads on such, I would be most grateful.
Cheers,
John.

Is this what you seek..?

Hi randyjawa , many thanks for the suggestion but not the right tubing or crown profile.
Trying (and failing, as usual) to find something akin to this:





...appearing to be unobtanium.
Very kind of you to take the trouble and truly grateful.
All the best,
John.

Hi randyjawa , many thanks for the suggestion but not the right tubing or crown profile.
Trying (and failing, as usual) to find something akin to this:





...appearing to be unobtanium.
Very kind of you to take the trouble and truly grateful.
All the best,
John.

I'm sure you already know this, but finding original replacement forks for vintage frames is difficult to say the least as it's often the first part to get damaged, and on the odd occasion they do come up for sale, you'll be spending more than what you could potentially get a new frame for. Add to that the required steerer length and the odds are against you.

My Pinarello came with an aluminium fork and I spent a good 12 months looking for an original, and the auction prices indicated I wasn't the only one looking for one! Eventually landed one from Serbia which cost about two thirds as much as I purchased the bike for. (Even then it wasn't exactly the right fork, but I wasn't going to turn down a Columbus Air fork.)

My only advice is set up a worldwide ebay search and keep your eye on ebay.it for listings that might not be advertised globally.

I don't think this will be much help re: your budget, but I scan eBay occasionally looking for a particular hard-to-find Italian fork for my own project. I have plenty of time since the bike has a functional fork (but it's not exactly correct) and I see a lot of forks for sale, many from Italian or EU sellers who seem to be professional strip-n-flippers. I do believe I have seen a few examples that have this sort of fork crown that you seek, but never paid them too much attention since that crown is not the one I am seeking. Short version: I think there may some out there on eBay; chances are you'll wade thru a LOT of ads before you find exactly the right size (let alone brand or color) and the trend I notice is with these sellers the prices are HIGH!

Cheers P!N20 & unworthy1 ,
Wise words indeed and good advice, all very much appreciated.
Prepared for the long haul and it will get sorted and usable as I have a (ok, fairly cr@ppy) fork that I can deploy in the meantime.
Eastern Europe from Slovenia to Poland certainly seems to be a rich source of parts.
The hunt continues...

FYI, fork crowns which appear to be continuous with ther blades, other than sometimes a small separation seam, are generically referred to as 'integral' fork crowns. This distinguishes them from a Unicrown, which can have a similar appearance but eliminates the traditonal crown by using fork blades with lateral curves at the top and that are (usually) TIG welded directly to the steering tube. Integral crowns date back to at least the first bicycle boom of the late 1890s but enjoyed a modern resurgence after Cinelli introduced his fully sloping version of the integral crown on the 1951 Cinelli Super Corsa.

Columbus Max forks are my favourite forks, I have them on 4 bikes, sorry they are all on bikes that are in use so don't have any for sale. I too am in the UK and they come up pretty infrequently/never here, and tend to fetch a premium. Coupled with the fact you need one with quite a long steerer, be prepared for the long haul, but they do come up, though I'm not sure you'll ever find a 'cheap' one.

As you said keep an eye on overseas sales, though post-Brexit this has already got more expensive. For the two bikes I bought the forks for separately, both for 57cm frames or larger, I had to wait over 2 years of searching eBay before I found anything suitable. I found this one on Italian eBay, so always worth keeping an eye on there as Columbus is Italian obviously.

And ever since I bought my ti Merckx I've been looking for a Max fork for it to replace the old carbon one it came with, and that frame is larger that 58cm so that was a long wait too. Only in the last month or so did I eventually find this beautiful fully chromed one, and that was from Western Siberia of all places.

So don't lose hope, they can be found, and the longer the wait the longer you have to save up, good luck!

Many thanks for the data T-Mar , very informative and interesting as always.

Thanks for the response botty kayer , you have shown me that there is hope yet!
Casting a wide net and waiting is definitely in order.
I have seen plenty of 80s & 90s forks going for very silly prices, even unbranded 700c jobs made with unknown tubing.
Well done on sourcing the two pairs that you found, Your patience certainly paid off.
Cheers,
John.

I just found out that you can change your location in eBay and then you will see items for sale in that area. I have found bits from Poland at reasonable prices. Who knew....

According to the Columbus website, MAX is still in production, though with an updated alloy. Still, the outward appearance is the same, so another approach would be to contact a custom builder to have one built, provided an aesthetically suitable crown is available.

That is an approach that I had considered, not least because it would involve less expense and time. I had found several sources for MAX tubing as well as fork crowns specifically for such but as you say, the right crown is somewhat more elusive. One or two I have seen are close(ish) but would need some grinding in my part which may compromise functional integrity.
It is an option that I will keep open with your caveats in mind.
Many, many thanks again,
John.

PM sent

Cheers Bianchigirll .

Some of the new- ish Japanese Keirin bikes are being made with Columbus max forks. NJS export has some up right now in their forks section. You probably need to confirm the rake etc. though

Higher prices than their other forks but obviously a much sweeter deal than going custom.

Cheers Bianchi pc ,
I have checked their site fairly regularly over the last few months. Still can't find the right crown profile but some crop up that are reasonably close(ish). I think that I will give them a tug as I will have the right tubing and a fair approximation of the right appearance and as you say, less than a custom build even if I source the fork elements myself.