Reinterpreting a 1978 Peugeot PR65

I’ve had a  blue 1978 Peugeot PR65 in my shop for some time.  The bike was 100% original when I acquired it, and is in beautiful condition.  I had put it together after its arrival from France, but was unhappy with the ergonomics and with some of the components.

There were two versions of the PR65 in 1978, but only one appears to have been built with the Reynolds 531 tubing used on this bike – the “luxe” model.

The paint quality is very nice, and the bike looks nearly new.  All of the nicer components of this era are present – a Stronglight TS 3 arm crankset with 48/38 rings, Mafac Racers, Mavic rims and Bluemels fenders to name a few.

Plastic Simplex components removed.

Simplex shifters removed.

But the incredibly uncomfortable ergonomics (long top tube combined with low stem and no rise porteur bars) along with the ugly plastic-infused Simplex components made me want to make some changes, which is not something I will usually do with a 100% original bike.  But, a bike that gets ridden is always a better bike than one that is not.

A good example of the hideousness of Simplex’ obsession with plastic during this era is shown above.  A normally elegant downtube cable guide is made into a bizarre monstrosity.  Often these plastic components will break, especially the plastic clamp for the front derailleur, so I also regard these plastic Simplex components as unreliable.

Simplex dropout as modified to accept both Shimano style and Huret derailleurs.

Notch engagement on the Huret derailleur.

B screw engagement for a Shimano style derailleur.

First up was the need to do something about the Simplex dropouts, since I wanted to have other rear derailleur options.  I decided to attempt to file notches in the the plain round unthreaded dropout, and to tap it out to 10M.  I created both a “7 o’clock” notch for Shimano style derailleurs, as well as a set of notches for Huret.  The process took quite a while, but I was successful.

Wanting to be true to the bike’s French heritage, I chose to use replace the Simplex components with Huret, selecting a Svelto for the rear derailleur.  The Huret front derailleur is a bottom pull style that needs housing, so an appropriate Huret cable guide with a housing stop is also needed, as shown above.

Replacing the bars was also not a simple swap, due to the French sized steerer tube.  Since I wanted to use a modern upright handlebar, I needed to sand an appropriate stem down to French size (22.2 to 22.0), which also takes a bit of time and patience.  This is a vintage Cinelli stem mated to a set of Nitto tourist bars.  I needed some strong and reliable shifters to handle the Svelto rear derailleur, and these lovely vintage Suntour bar mounts do a great job.

The bike as now configured is amazingly comfortable – perfect for commuting and for exploring.  If I were to keep this bike, I would probably cold set the rear triangle to 126mm (from 120mm), and build a set of 650b wheels around a nice, vintage hubset.  This would allow use of wider tires than the 700c x 28mm tires shown above, which is about as wide as the bike will accept with the Bluemels fenders.  I’m planning to list this bike soon on my store page, so I’m hoping it will find a new home and have a chance to get back out on the road, as the bike certainly has many miles to go, and will get you there in true French style.

Dropping Out

Early 1950’s Simplex dropout – long, horizontal, with eyelet.

Rear dropouts determine what derailleur options are available for a given frame. Rear dropout spacing also determines hub options, with derailleur equipped vintage bicycles having narrower spacing than their modern counterparts.  And, the shape and style of the dropout are important as well:  horizontal dropouts allow for wheel adjustment fore and aft, whereas vertical dropouts make rear wheel removal easier.  Eyelets on the dropouts mean integrated fender and rack mounts, a definite plus.

Little attention is paid to this important feature of any vintage steel bicycle. Vintage dropouts include:  old style Simplex dropouts (shown above – but often model specific), newer style Simplex dropouts,  Huret drop outs (several styles), Campagnolo dropouts, Shimano and Suntour dropouts, and stamped or forged dropouts with no integrated derailleur hanger. Some vintage bicycles feature chainstays with integrated braze-ons or dropouts for Simplex, Cyclo, Huret and other rear derailleurs.

Chainstay braze-on for a Cyclo rear derailleur

1947 Simplex TDF with claw mount

Plain dropouts require a “claw” attachment for the rear derailleur or a braze-on or clamp for the chain stay.  For vintage bicycles, plain dropouts without a hanger do not in any way indicate a lower end frame.  Many nice upper end vintage steel frames did not have manufacturer specific brazed dropouts.  So, do not be afraid of the “claw”.  In fact, having plain dropouts on a vintage bicycle can be helpful, because derailleur options are automatically expanded, depending on the style of claw chosen.

The above Daniel Rebour drawings depict two different styles of Huret dropouts.  Huret rear derailleurs can be a bit (translate “a lot”!) more difficult to set up than Simplex derailleurs. By contrast, setting up Shimano, Suntour or Campagnolo derailleurs with their matching tabbed and threaded dropout at 7 o’clock seems almost too easy.

1972 Mercian Shimano dropout

After the early 1980’s or so, dropout hangers were not so much an issue, because dropouts on derailleur equipped bikes after this point in time featured standard Shimano/Campagnolo hangers which were adopted as the standard by other component manufacturers.

Sheldon Brown’s dropout chart

Sheldon Brown developed this helpful chart shown above, although it is missing some key information.  He does not address the baffling array of hanger styles which existed in days of yore.

A Simplex early style dropout with tab on the non drive side.

Hangerless dropout, requiring a claw

Campagnolo semi-horizontal dropouts on a 1970’s Jack Taylor

Stamped plain dropouts on an early 1970’s Raleigh with a 531 frame

There is only one resource on the web that seems to have a comprehensive overview of dropout styles and rear derailleur compatibility issues.  This helpful chart can be found at a site called The Headbadge.  Velobase also has an extensive database of vintage style dropouts. These resources can help anyone restoring a vintage bicycle determine whether and how to change the existing rear derailleur, and how to determine compatibility options.

In addition, there are a few other web resources that can help you with derailleur and dropout considerations:

An early 1978 article on derailleurs and dropouts by Sheldon Brown, with interesting discussion of Type H and Type S rear derailleurs.

An historic overview of gear selection options through the decades by Bainbridge Classic Cycles, featuring an interesting photo of a freewheel with moveable cogs and a stationary rear derailleur.

The Dancing Chain by Frank Berto is also an important resource – even more so because it is in book form.  If you don’t want to explore vintage derailleurs and dropout styles, the information presented in Chapter 15 – “How Derailleurs Work” will be worth the cost of purchasing this book.  The author’s discussion of derailleur composition, chain gap, pulley spacing, cage geometry, and spring loaded pivots is invaluable to an understanding of how derailleurs work.

1953 Follis with integrated two hole Simplex bracket