jyl

Once upon a time, a man was invited to ride a bicycle unlike any he'd known. The experience was remarkable. He remembered it, thought about it, and years later mentioned it to another man. They were riding in the rain. The second man happened to know all about this kind of bicycle, and pointed out to the first man that a long-neglected bike in his, the first man's, garage would be perfect for such a project. He also said "n + 1", and said it with authority, for he, the second man, was An Engineer.

So a 55 year old bicycle, that once looked like this:



before spending the next few years as pieces in a box, is going to be rebuilt. This is the starting point:



Yes, @gugie and I are going to build me a 650B randonneur from my 1961 Bianchi Speciallissima!

I test rode a 650B randonneur from Velocult's fleet, probably the first week that Velocult was open in Portland. I remember how the cracked pavement and lumpy aggregate on the surrounding streets, that had just rattled my gonads on my 25 mm 120 psi Frenchie racy bike, magically smoothed away under 42 mm 50 psi Hetres.

A couple years later, when building my daughter's college bike, a UO-8 with 32 mm tires and a porteur rack, I learned how stable a lower trail bike feels, even with a load on the front wheel.

Then I found this battered old Bianchi, and bought it for the long term project that I didn't quite have in mind. One thing, another, and nothing was ever done to the bike. The frameset hung, dusty. The parts sat, boxed. I needed a spark. My chat with @gugie was that spark.

The frameset went to his bike operating room / Batcave this week. @gugie measured the frame, test fitted wheels with phat tires, tried on some brakes, re-raked the fork to an offset for low trail geometry, spread the dropouts to 130 mm, aligned the dropouts. You can read more about it here (Mark's Flicker page):

https://m.flickr.com/#/photos/115397...7663990636022/

Next steps are for me to order and build up some 650B wheels with a CS-RF3 rear hub (three speed IGH + 8 speed cassette) and a generator front hub (Shutter Precision, I think). Then reassemble the bike with the original components, which include Campagnolo Record (not Nuovo) and Grand Sport, Universal, and a few Bianchi-stamped parts, and a narrow-range 8 speed cassette. Leaving the cosmetics in their current woeful state.

And take some rides. If the bike speaks to me - nay, sings an opera to me - then I will tear the bike down again and deliver the frameset back to @gugie, who will have his brazing torch ready. From there, it will go somewhere and get painted, or coated. Then bring on the accessories. Handlebar bag, lights, fenders, all the randonneur eye candy. And a beret. And a baguette.

Sir_Name 

What a cool project. There's nothing cookie cutter about it. The ~sleeper drivetrain is an interesting idea.

clasher

Sweet bike! Personally I don't understand why you'd want that 3 speed hub, it weighs over 2lbs without anything else attached to it. Personally I love the look of the old paint, I would just clear-coat it... patina like that can't be beat imho, plus you've gotta grind off the chrome if there is gonna be stuff brazed onto it.

nlerner

I agree--cool project, but ditch that boat anchor rear hub idea.

jyl

Need the IGH for gearing. I want to keep as much of the original components and look as possible. As shown in the first picture, that is the smallest chainring the crank will fit, and close to the largest cog the derailleur will reach. 44 x 26 is sometimes not going to be low enough, especially if the bike is loaded up. The low 1st gear of the CS-RF3 (-25% from 2nd gear, which is direct drive) will make that the equivalent of 44 x 35. Or 34 x 28.

velofinds

I'd love to own a Bianchi Specialissima, whether built up as 700c or 650b. But if your 25mm tires were pumped up to 120psi, I might surmise that they were (probably) overinflated.

bikemig 

There are other ways to get the gearing you want without going the IGH route. You could get a strong light 99 triple (there is one in the C&V forum for sale), get a bigger freewheel, and the long cages for your NR RD. Just sayin' the IGH sounds like a complicated way to deal with the problem.

trailangel

Ouch!
You shouldn't ride 25mm at 120 pounds.
If you have already started.. continue.
If haven't already started I would try to talk you out of doing this to that bike.

gugie 

Sounds like this is devolving into a tire pressure thread...folks, @jyl has already stated he wants to go fatter, lower pressure, so this is a moot point.

At any rate, I'm excited to work with him on this bike. As for IGH, that's a personal decision, one I will support either direction.

If the ride is right, and we move forward with frame mods...
@clasher, the chrome that counts (socks and lugs) will be saved if deemed good enough to do so. Some of the lugs look pretty rusty. The oxalic bath method will be used to remove rust, and a decision can be made whether to mask at that point. I don't plan on "grinding" any chrome off for brazed bits, 80 grit garnet paper works just fine!

nlerner

I think it's a great idea to go phat, but my comment about the IGH has mostly to do with the performance (or lack thereof) you get. I'm all for IGH bikes (I have a dozen or so), but I haven't been happy with road bikes fitted with 7- or 8-speed IGHs. The weight penalty has made the ride overall disappointing, no matter how wide the tires. That said, if you've ridden this hub/gear combo and know it works for you, go for it. If not, maybe there are ways you can experiment with period-close mechs that'll work for a wide-range double.

jyl

Here's my thinking.

My goal is to preserve the Bianchi's original drivetrain (including 151 BCD crank). I like the look of it and am interested in trying the half-step gearing. The IGH+cassette hub, with a close range cassette, should allow me to do that. I have some ideas for disguising the fat barrel of the SA hub and the third shifter.

This will be a rather heavy bike no matter what. The original bike is no lightweight (it weighs about what you'd expect for a 1961 bike - lot of steel in the components). It will be larded with gen hub, lights, fenders, racks, bags, tools, pump, etc. I'm expecting 30-35 lb ready to ride. That's okay. I have a racy weightweenie C&V bike already, don't need another.

The bike is cosmetically kind of a mess, a "heavy patina" description is generous. It also has repaired crash damage. Also an interesting backstory, when I sleuthed the name and address on a cracked Dymo tape label (shown in @gugie's Flicker pictures). A thread from when I found the bike, a few years ago:

https://www.bikeforums.net/classic-vi...d-bianchi.html

I thought I'd posted the backstory once, but can't find that old post.

noglider 

This is fun!

I don't know if you saw me mention it on other threads, but I am so enthralled with my Raleigh International that I am tempted to replace all my other bikes with a fleet of Internationals. Well, not really, but that's how much I like it. The geometry of the Specialissima looks similar.

Is love for fat low pressure tires a function of age?

Right now, I have 28mm Ruffy Tuffys, which are, of course, not wide. My body weight is down to 158 lbs, so I inflated the tires to 65/60 and didn't come close to causing a pinch flat. I think I'll try lowering the pressure further. I'd love to try 650B one day, but I'm still happy with 700c.

Sorry for my post being about me and my bike rather than yours. I hope you see the similarities, though the differences are there, too.

due ruote 

Is there a way to add a small chainring to that crankset?

Cool project. You are clearly being thoughtful about it and have talented hands involved. Hope it turns out as good as you imagine. It will be fun to follow along.

John E

I like it. I ran a Sturmey AW with a 14-16-18-20 Cyclo cog block and 40T up front, which gave me the equivalent of a 53-40-30/14-16-18-20 pure derailleur system. I would have loved to make my setup into a 40-38 half-step.

Salamandrine 

Interesting project, and oddly enough it makes a certain amount of sense to me. I bet this will be the world's first 48 speed Bianchi!

Have you worked out a gear chart yet? Sounds tedious and I don't envy you, but I think if it's not done carefully, you'll have more duplicate gears than not.

EDIT: Duh, Sheldon Brown's gear calculator can handle this combo. That makes it easy, or at least easier.

BTW, normally half step worked with a 5 speed rear that was not close ratio, as every rear cog had two gears.

bikingshearer 

My 1961 Bianchi Competizione (literally a barn find c.1974) as it came to me almost beat him to it. It had a cottered triple crankset mated to a five-speed freewheel mounted on a three-speed hub. Yes, it really was a 45-speed, I kid thee not.

No, I have no pics, so by the rules of BF it technically never happened, but it can be done.

No, I never rode it in that configuration - I was a teenager with delusions of racing ans such a set-up simply would not do.

And no, I did not keep the old components, either.

Still have the frame, though, repainted and decked out with period-appropriate stuff. It was my ride at Eroica California last April.

To the OP, good on ya for breathing new life into a frame that richly deserves it. Enjoy.

gugie 

Tom, I'm looking at my International next to the Specialissima, very similar, but my chain stays are longer. But then, my International has exceptionally long chain stays, even for a 73 International! Seat tube angle is more upright on the Specialissima. I'll post the geometry before and after fork rerake tonite.

I resemble that remark.

jyl

Played on St. Sheldon's calculator. Looks like 46/44 chainrings x 12-23 8-speed cassette x SA hub wide range gives

- Three ranges of gears, corresponding to SA hub 1 (-25%), 2 (direct), 3 (+33%)
- In range 2 (SA hub 2nd gear), goes from GI 50 to GI 100 with steps of 3-4 GI and no duplicate gears. This seems like a good everyday range, and it is the IGH's direct drive gear.
- In range 1 (SA hub 1st gear), goes from GI 37 to GI 75 with steps of 2.5-3.0 GI and no dupes. This seems good for steep or loaded climbs.
- In range 3 (SA hub 3rd gear), goes from GI 66 to GI 133, with steps of 5-6 GI, no dupes. This would be for tailwinds.
- I doubt I'd shift gears on the SA hub very often - more like "entering hills, shift to 1", pant, pant, pant for 20 minutes, then "leaving hills, shift to 2".
- Most of the time, all shifts would be on the derailleurs. Steps between adjacent gears would be about half the size of most steps using same cassette and a 53/39.

Perhaps traditional half step used wide range freewheel, because that's the only way to get a reasonably large range from lowest to highest. With the SA hub, that would not be a constraint.

Salamandrine 

Sounds like you've got it pretty well worked out. Thinking of it as 3 different ranges is sensible. That's sort of like the way double chainrings were treated on 60s bikes with their 45/52 etc. They didn't try to make a perfect spread, but rather a nice range for hills, and a nice range for flats. I guess the SA "range 3" is a bit unnecessary except for long downhills, but it does give you bragging rights. You'll probably be able to use the direct range most of the time, which would avoid most of the planetary gear efficiency losses.

jyl

What is a good 650B rim? Looking for shiny silver, wide enough for Hetres, 32 or 36H. I don't think I'm too concerned about aero profile. Maybe a budget choice and a "money is no object" choice?

clasher

The soma weymouth rim is listed at 60$ on their store. I dunno where to buy just the rims but you can get a ZAC 19 wheelset for a hundred bucks. Top of the line (or more expensive) would probably be the Grand Bois offerings from Compass or the Velocity A23 but the Velocity synergy looks more classic. I have no experience with any of these rims.

Sir_Name 

Velocity Synergy is a good one, easy to build and plenty stout. Wide enough for Hetres. The rear is offered with offset drilling, which is nice. The current set I have is 36h rear, 32h front - I love 'em. I believe Pacenti also has a high quality offering in 650b, but my only experience with them is reading about them on the internet...

jonwvara 

Great project. I vote for not painting. I have never done a repaint that I didn't come to regret. It's impossible to regret not painting something, since you can always paint it later.

jyl

I'm not averse to patina, so we'll see how it goes, but I think the frame, left unpainted, will look even worse after stuff is brazed on.

The Soma rims and the Synergy rims look nice, thank you. I'll pay with a spoke tension calculator to see if I really need the OC feature of the Synergy. I see VO has a shiny 650B rim as well.

tarwheel 

That frame is just calling for some new Celeste green paint and retro Bianchi decals in red or black.