Tag Archives: Simplex TDF

Simplex Tour de France Rear Derailleur Adjustment

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It’s been quite a few years since I last posted about how to set up a Simplex Tour de France rear derailleur.  These mechanisms were found on bikes dating from the late 1940’s to the early 1960’s, but are not in any way intuitive to fine tune.

The routing of the chain through the pulleys was so puzzling that Simplex had to include a chart in their technical instructions to indicate how this was to be done.  In fact, when I had first started my vintage bike restoration endeavors many years ago I had taken a vintage Peugeot to a reputable bike shop for some repair help with a rear wheel.  When the bike was returned to me, the chain had been incorrectly routed through the Simplex rear derailleur.  That shows just how perplexing this rear derailleur can be.

1953 French mystery mixte with Oscar Egg lugs

Recently, I have been working on my mystery French mixte with its Oscar Egg lugs.  The bike was equipped with tubulars which have proven to be a challenge to keep maintained, as I haven’t ridden this bike on a regular basis, even though they do offer a beautiful and comfortable ride. The glue holding the tires to the rims is no longer robust.  So, upon deciding to temporarily replace the tubular wheelset with a clincher set from the same early 1950’s era, I needed to perform a few tweaks to the Simplex TDF rear derailleur in order to get this bike set up so that I can ride it with more regularity.

My replacement clincher wheels are 700c 1950’s Super Champion rims laced to Normandy hubs.  I wanted to lower the gearing from the the original configuration, but had read that these rear derailleurs can only manage about 24-25 teeth maximum on the freewheel.  I found a 5 speed freewheel with French threads with a largest 25 tooth cog, and then adjusted the internal threaded shaft on the Simplex TDF rear derailleur to tune out the highest fifth gear, as this derailleur can only accommodate 4 gears.  (The bikes’ original drilled Regina freewheel’s largest cog is 21T).  This is accomplished by loosening and removing the nut on top of the knurled washer, and turning the threaded shaft as needed to position it correctly so that the chain lines up with the smallest and largest cogs as the pull chain is moved through its range of motion.  It takes a bit of trial and error.  The knurled nut is meant to be used to turn the shaft, but if that proves difficult, there are flats on the shaft which engage with a 12mm wrench.

Once the alignment to the cogs was correct, I proceeded to adjust the derailleur using the two spring tension adjustments available in this 1950’s rear derailluer:  chain tension, and pulley tension.  The chain tension is controlled by the spring on the arm, and the pulley tension is controlled by the tension on the pulley spring, using the notched mechanism, shown above.  Moving the pulley spring’s position clockwise increases the pulley tension.

Before going further into the weeds, it’s always a good idea to look at a component’s schematics.  Here is the front page of the TDF instruction guide included with these models.  I also consulted the excellent advice from Peter Underwood at the Classic Lightweights website.  After some contemplation, I decided to overhaul a NOS Simplex TDF that I had in inventory, which needed cleaning and re-greasing, hoping this would illuminate this derailleur model’s nuances.

Upon removing the outer nut with a 17mm wrench, I proceeded to removed the pulley cage, which takes an 11m wrench.  The outer steel flexible cover over the shaft reveals an internal spring.  This model had lots of extra washers, which I ended up not replacing (more later!).  After cleaning and lubricating all the parts, came the difficult task of getting the pulley cage back on to the shaft, with its attendant spring.  After some trial and error, I realized there is always a trick to getting derailleur spring back where it should be.

After taking time to review the schematics, I realized that I needed to move the threaded shaft as close as possible to the notched piece, so as to push the moveable part of the shaft down as far as possible.  While holding the spring and cover tightly in place, I was finally able to thread the pulley cage back on, sans a few washers!

And finally, I was successful at re-assembly.  This NOS derailleur now has free-running pulleys with all parts lubricated and is ready to roll.

Meanwhile, I had tried various adjustment scenarios, changing the chain tension and the pulley tension.  The above is a video I made discussing the various adjustments possible for this derailleur.  I initially set the chain tension to push the derailleur back so that I could use the 25T freewheel I had selected.  But, you will see from this video, that by doing so, my shifting performance has suffered.

So I decided to reduce the chain tension by adjusting the nut at the back of the mounting bolt (which has the chain tension spring threaded around it).  This is done by removing the spring from the arm, releasing the bolt, moving the spring back or forward (in this case, forward to reduce tension), and re-tightening the nut.

You can see from the above video that my shifting has improved dramatically.  However, upon taking the bike on a test ride, the torque on the drive train while riding caused the derailleur pulley to contact the 25T cog, making the bike unrideable in that gear.  So, back to the drawing board!  I’ll either switch the freewheel back down to a 24T model, or fiddle with the tension adjustments yet again (NOT!), and most likley swap out the front chain ring for something a bit smaller to help make this bike more rideable for a Portland commute.

A Tale of Two Three Speeds

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Last fall I relocated our offices to the Laurelhurst neighborhood in Northeast Portland.  Now, I commute to work in a lovely and historic part of Portland’s awesome east side, leaving behind the stressful and gnarly traffic surrounding our old Victorian on SW 5th near PSU.  I usually commute on one of my daily riders, but also keep extra bikes on hand at the office for errands and lunchtime rides through the neighborhood, including my two favorite 3 speeds:  a 1950 Raleigh Sports Tourist, and a 1947 Peugeot PH55.  I restored both bikes many years ago, but the Peugeot was a more involved process because many of its original parts were missing.

The restoration process involved sourcing a vintage 650b wheelset and fenders, as well as handlebars, stem, brake levers, saddle, dynamo, lamps, and saddle.

My goal was to come as close as possible to the bike featured in this 1947 Peugeot catalog, and to err on the higher quality side when possible.

I think I achieved this objective and am happy with the way the build came together.  The NOS Ducel dynamo lights work well without excessive drag.  The bike is much lighter than its Raleigh counterpart, weighing in at a respectable 28 lbs. compared with the Raleigh’s 45 lb. bulk.  This is because the tubing is high quality Rubis, and the bike features many alloy components.

The Peugeot’s drive train is all original, with a 19-24 “Twister” freewheel, Simplex TDF rear derailleur and Peugeot 46T crankset.  That puts the gear inch range, with its 650b wheel size, at 50 to 63.  Very narrow and with no low or high gears.  The Simplex TDF shifts just fine, but needs a bit of correction both shifting up and down the gear range.

The Raleigh’s drive train is, of course, a Sturmey Archer internally geared hub, mated to a 46T Raleigh crankset, which is fully enclosed in its full length chain guard.  The AW hub with its 19T cog gives a gear inch range of 47 – 84.  A much wider range than the Peugeot, but mostly very high, especially given its bulk.

The Raleigh has steel rims, as compared to the Peugeot’s lightweight alloy Super Champion rims.  Both wheel sizes are similar, and both bikes feature full length fenders.  The Raleigh’s are steel (of course!) and somewhat mangled from years of use, and the Peugeot’s are lighter weight alloy.  All of these elements contribute to the significant weight difference between the two bikes.

1950 Raleigh Sports Tourist

So, what bike wins my vote?  Believe it or not, it’s the Raleigh.  While it is MUCH more challenging to conquer hills on the Raleigh, the comfort and quality of this machine is no match for its highly competent counterpart.  The bike kind of self-propels once it gets going, due to the inertia of the heavy wheels.  And, the convenience of shifting whether stopped or not adds to this bike’s appeal.  It’s the bike I most often select for neighborhood jaunts, even though I may have to stand up and stomp to get it up the hills.  It’s a pleasure to ride and gives me a great workout.  And, it’s a reminder of what it’s like to experience the quality and craftsmanship of this era’s legendary Raleigh marque.