Biketiger

I was so excited to receive the latest addition to my addiction collection of track bikes. When the black cherry Ciocc arrived I realized that I could not fit even a 23mm Continental GP 5000 on a Rigida rim. My mechanic suggested I seat the front wheel slightly higher off the axle. Not riding that. I read threads here suggesting shims for the blades using wire and glue. Ain't going to happen here. I don't ride tubs (and I ride vintage track bikes, right?) and if I ever do, there not going to be 21's which were probably what this bike had. So...
I bought a dremel and went to town. I'm sorry I did not take a before pic but there was barely a curve in the crown, just the slightest indentation. My plan was to gradually increase it until a 25mm clincher would fit. I did not inscribe a line in the steel but instead checked the fit repeatedly throughout the grinding process.
But I soon discovered after grinding away and sparks started to fly that I was on my own. I lost the original curve which was barely there anyway and now I'm having to carve a new curve.
It is now custom cut to fit the Continental 25s I ride. So, how did I do?
I'll post a pic of the whole bike tomorrow, it's too dark now.


As originally equipped with sew-ups

Biketiger

Here's a better pic of the crown

squirtdad

your bike, your choice

personally I wouldn't have done it

why bother with vintage track bikes if this is what it takes?

also 21 tubies would have been pretty darn close to comfort and a better ride than the 25mm clinchers

I am assuming you are riding on the street

norskagent

650b track wheels!

steelbikeguy

Tight clearances for a 21mm tubular tire isn't unknown for track bikes. In fact, it seems to have been a perceived advantage. Maybe it showed that all of the tubes were as short and stiff as possible?
All I know for sure is that this 1975 review of a Masi track bike (built by some guy named Confente) had a very tight clearance at the crown.



Steve in Peoria

Biketiger

I have some nice road bikes but I ride track bikes almost exclusively - on a paved path. Why bother riding track bikes? They're awesome machines. Of the nine I own, the Ciocc is the only one I had to modify. It's tied at number one with the Cinelli SC for sheer ride quality. I am not kidding and I was not expecting this from a Ciocc. I just bought it for the name!

Biketiger

Thanks for posting that Steve - tight at 21! I read on BF that skinny tubulars were trendy in the early 80s.
I never saw a Miyata track bike before - cool!

retswerb

I'd be inclined to go back and round the corners / chamfer the edges but really just for appearance more than anything. If this has gotten you the ride you want, more power to you.

clubman 

Awesome machines is so right. To be young(er) and riding Japanese track bikes again. Ciocc or others, great!

Biketiger

I have a set of files. I plan on applying a coat of primer to the underside and mixing up some Testor paint.
Can you say more about how I could round the corners? Do you mean just smooth out the edge? It's freshly cut.

retswerb

Yep, just smoothing out the edges with the dremel or files - doesn't take much, but enough to make them nicely rounded and not sharp to the touch.

Biketiger

Thanks so much for suggesting that! I want to do the best job I can!
I'll try the Dremel because it's a really easy tool to control. I forgot to state that I started with a file for the crown but was making very little progress and files slip and scratch.

Biketiger

I'll post a pic of the finished job - thanks again for your suggestion Retswerb.
Thanks for everyone's comments. And to those who disapprove or are possibly even horrified I offer this:
I have ridden many many bikes and this one spoke to me. I didn't hear it out loud of course but the first time I rode the Ciocc it conveyed, thank you for riding me, Ride ME!
I never heard that from a bike before. Like it was sad for sitting for so long.
It had been sitting as pictured above for decades. And now it's going to be ridden, a lot.
One more thing about that crown, from a foot away - most folks will never know!

xiaoman1 

Seem plausible, 650c-584mm and 700c- 622mm...38mm difference.
Best, Ben

Biketiger

So many interesting ideas! And I forgot to mention in all my posts that I did my homework here on BF and it was not uncommon to file track forks - someone had mentioned this in a recent thread. There was a dispute about grinding off a derailleur hanger vs cutting a crown in terms of modifying vs molesting a frame. I couldn't find that post but I remember reading it recently.
Several other threads over the years mentioned grinding or filing. I learned it here

unworthy1

Just to add my 2 cents: never had to modify the underside of a track fork but I have done it to a couple road forks, and I have used my Dremel(s) hundreds of times on many projects.

I find exactly the opposite: I get into trouble with the Dremel catching, grabbing and going where it should not (at high speed) far more often than with good sharp files (or sandpaper on a block).

I have found I need to brace the Dremel so I can really limit the range of motion for it to be "safe cutting". Whenever I just wing it and go at something using the Dremel as a "hand tool" (which it certainly seems to be) I almost always regret that.
YMMV

Biketiger

The dremel is amazing. I can see why it's such a popular tool. I already used the wire wheel attachment to buff out a lot of the deep scratch that came on my Vanilla bike's custom steel bars. Which attachment works best buffing out scratches in steel?
I'm sure your right about controlling the dremel. YMMV? All my miles will be on the bike

Andy_K 

I think it looks great. Nice work!

Biketiger

Thanks Andy - you made my night! I'll smile a little wider riding it tomorrow. I'll get it prepped and painted this weekend and post the final result.

Trakhak

My 1982 Bianchi Eco Pista came from the factory with the underside of the fork crown crudely filed to accommodate its road-sized tubulars. The foreman probably assigned the task to the biggest chooch on the payroll.

Noun: chooch (plural chooches) (Italian slang) A stupid person; a meathead.

If you ever wondered where the name "Ciöcc" came from---there's your answer! (Read that years ago in an interview; when asked about the name, the importer, or whoever it was, said something like, "Well, in Italian it means your fun-loving, good-for-nothing uncle.")

bulgie 

IMHO a half-round file is the correct tool for that, it makes a smooth continuous arc automatically, versus making it with a Dremel by taking a little off here, a little there, by eye. Oops too much there, now I have to take some off here, oops too much...

But I have put in my time filing to where it's easy for me. Maybe I forget what it was like to be a beginner at filing shapes. A Dremel seems more controllable to you? The Dremel seems more dangerous to me.

I have no problem in general with putting a tire-clearance radius in a crown, whether road or track. Here's a road fork I made for myself in the '80s:


No, the radius is not an afterthought or correcting a goof, it was designed that way. Sort of a stylistic nod to track crowns.
I use Challenge Parigi-Roubaix 30 mm tires on that bike.

Speaking of track, the divot for tire clearance in track crowns is so common as to qualify as "traditional". Here's a nice Nagasawa crown by Takahashi, casting by Hitachi. Note it has the divot cast-in:



Fun fact (OK maybe not so fun, and maybe obvious?!)
The divot needs to be deeper in the front of the crown, to where there's often zero divot in the rear. But the less fork rake (offset) you have, the more the rear divot you need. Track forks often have little rake, so they're more likely to get some divot in the back as well as the deeper one in front. That's why my pink road fork above has no divot in back, but the Nagasawa crown comes with 'some' divot in the casting in back. Ideally the tire clearance will be the same in the front and back of the crown, if you divot it at the correct angle for your rake.

Mark B

Road Fan

My first ones were back in the early 1970s, d'Allessandro. 21mm trendy is not the word! That was about all you could get except for some armored ones like Clement Elvezia and Hutchinsons - both very thick-treaded tires.

Trakhak

In the mid-'60s, I rode Pirelli Gran Premios (26 mm) and some other tire brand I can't remember. Clement had wide (maybe around 30 mm) Paris-Roubaix and Campione Del Mundo tires, too. My Helyett Speciale track bike that was given to me by my parents in 1964 came with fairly wide Dunlop tubulars. No model name that I can recall, but I believe they were marked as weighing 10 oz.

Biketiger

Bulgie - thanks for your reply & insight! Yes - you are right on both counts. I started with the file but gave up when I saw how little metal dust was accumulating on the floor. Filing is another skill. In terms of control, I am sure you can be more precise with a file.
And yes, I did have to make a divot in the back - albeit smaller.
Beautiful crown you made - especially that curve in the middle, very suave.

52telecaster

Excellent. You gotta ride what calls your name.