Monthly Archives: March 2018

Love the One You’re With

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Whenever I ride my 1980’s Guerciotti I am amazed at its performance.  It is more responsive and faster than any of my other bikes, some of which are no slouches in the performance department.  The only reason I don’t ride this bike more often is that 650c tire sizes are limited to fairly narrow widths, and given its racing heritage, it can’t (and doesn’t want to) haul a bunch of stuff.

The frame is built with Columbus Aelle tubing.  The seat stays are small diameter, and the fork crown and seat cluster feature beautiful engravings accented with white paint against the royal blue main color.

I used Paul’s thumbies to bring the shifters up to the bar.  The Tektro long reach brakes worked perfectly for this wheel size conversion (from 700c to 650c).

The frame had no eyelets or braze-ons for racks and fenders.  So, I used zip ties to secure the fenders at the rear and p-clamps for the front fenders and front rack.

In keeping with its Italian heritage, I used a Campagnolo crankset, bottom bracket, and headset when building up the bike.  The crankset’s arms are 170mm, and if I were to replace the crankset I would choose one with shorter arms as to address the low bottom bracket height after the conversion to 650c.

After 5 years of use, all these modifications are still working perfectly – it is a delight to ride and handles beautifully.

 

Cantilever Conundrum

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4 different cantis – vintage to modern- Mafac Criterium; Shimano BR-AT50; Dia Compe 960; Shimano BR-R550

An upcoming bike build will need cantilever brakes.  The frame is new (more on that later), but vintage cantis would not be inappropriate for the project.  As I am not a fan of V-brakes for road bikes, I am exploring the many cantilever options which are available for a frame with canti braze-ons.

Modern cantilever brake options include Paul’s, shown above, as well as other models from Shimano, Dia Compe, Velo-Orange, Avid, and Tektro..  With all these alternatives, it can be hard to determine the best set of cantilevers for a given application.

Shimano BR-R550 with integrated springs

Beautiful Dia Compe 960 Cantis – in as new condition.

But before that a primer on cantilever brakes was in order.  While there are many factors to consider, one of the important ones involves whether you want your springs integrated into the brake or not.  Newer cantilevers, such as the Shimano’s shown in the top photo, have integrated springs that allow for separate spring tension adjustment on each caliper.  Older cantis, such as the Dia Compe’s in the lower photo above have external springs.  The only way to adjust spring tension on older cantis is to mount the spring into a different hole on the canti brake boss (some bosses have 3 separate holes to allow for this).  Or, the spring can be modified with “strong arm” force by changing its shape.

Fortunately, the bike I am working on has 3 hole canti bosses, so I can take the time to evaluate vintage vs. modern caliper options.

1940’s Mafac Cantilever boss

If you have a newer bike and you want to change your cantilever bosses, you can unscrew them from the frame and add a different plate or a different length stud.  Paragon Machine Works is a good resource for sourcing canti studs and plates.

Meanwhile, one has to wonder about the shape and angle of the caliper arms.  It would seem logical to conclude that the arms with the widest angle would have the most mechanical advantage.

But apparently one must think again.  Low profile cantilever brakes can have as much mechanical advantage as calipers with a more extreme angle.  Why?  It all depends on the position of the straddle cable, according to Sheldon Brown.

I experienced this when setting up Tektro canti’s on my 1987 Panasonic commuter bike.  I had to position  the straddle cable very low, but in doing so I found that the brake performed quite well.  The rule of thumb is to not set the yoke below the bottom of the fork crown.  While the angle of the straddle cable looks extreme, the brakes work just fine.

The Mafac cantilevers in my collection are the lightest weight calipers among the group.  Their springs are external of course,  but with the 3 hole option on the frame’s canti bosses, I am leaning toward installing them.  We’ll see!

A Mystery Vintage Touring Bike Courtesy of Fred DeLong

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I discovered Fred Delong’s publications much too late in my life.  DeLong’s Guide to Bicycles and Bicycling, first published in 1974 (the year I graduated from high school), is a treasure trove of both technical and non-geeky information, and includes photos and material I have never seen elsewhere.

Fred was a lifelong cyclist, author, and bike guru, and was inducted into the U.S. Bicycling Hall of Fame in 2001, six years after he passed away in 1995.

His book is unusual for its time in American cycle publishing.  It features French, Italian, and British built bicycles, and includes discussions of 650b tires with supple sidewalls mounted on low trail camping bikes, avoidance of toe overlap on touring bikes, and the importance of clearance in frame builds to allow for wider tires, as well as eyelets and baze-ons for fenders and racks.  Sound familiar?

The above photos are close up crops of the original photo shown as figure 2.11 in DeLong’s 1974 guide.  While most of the other photos in the book contain credits or are otherwise referenced, this image was not referenced or credited anywhere in the book.  That means we don’t know who built this bike.

So, let’s start with what we do know about this bike.  According to DeLong, this bike’s features are as follows:

“Wide tubular platform carrier with pannier bags mounted…

Hollow aluminum alloy rims on Phil Wood sealed precision bearing hubs…

Alloy mudguards, front with sliding fender flap in raised position and built-generator lighting…

Mafac Cantilever tandem brakes, rear brake cable direct routing (200 degree cable arc) with hooded levers

Aluminum alloy Randonneur handlebars

531 chrome-molybdenum braze-welded frame – 71 degree head and seat tube angles

15-speed wide-range gearing (23-116) on TA alloy crank and chainwheel set.”

Remember, this book was published in 1974. The photos in the book are all probably from at least one or two years earlier.  Phil Wood founded his hub manufacturing company back in 1971 when, as a racer he became frustrated with hubs developing play and needing an overhaul after each competition. That led him to explore sealed bearing designs for hubs and bottom brackets.  By the time of the 1976 BikeCentennial, Phil Wood’s hubs were all the rave, with touring cyclists ordering up Phil Wood hubs for their wheel builds, in preparation for a cross-country journey.

The above photo depicts an extremely unusual (for the time) sloping top tube.  The builder’s logos are not clear enough to make out, but the down tube seems to indicate “XP SR”.  The seat tube reflects some circular and elliptical logos, presumably also indicating the builder/manufacturer and/or frame tubing transfers.  Is this a custom frame?  I think not.  A custom frame wouldn’t ordinarily have what appear to be model monikers on the down tube. As DeLong indicates in the text, the frame is made of 531 steel and is fillet brazed.  The rear brake features through the frame routing for the “200 degree” cable arc.  While not necessarily a custom feature, it is also certainly unusual for a non-custom frame built in the early 1970’s.

The other intriguing elements of this bike include:

An extension (presumably) on the Mafac levers

A cover (or something similar) on the rear derailleur

A front tire which appears to be wider than the rear tire

A very long reach stem – possibly to accommodate a shorter than desired top tube length

Generous fork rake combined with slack angles

Half step gearing with a tiny third ring

Who made this bike?  Ideas and speculations are welcome.  In the meantime, I discovered a bicycle ridden by DeLong which went up for sale a while back.  The photo below shows the bike, a French JB Louvet built with Reynolds 531 tubing, in disrepair.  But, it may give some clues about DeLong’s interests and preferences.

Fred Delong’s JB Louvet – courtesy of http://bikeville.blogspot.com/