About Nola Wilken

Cycling enthusiast and owner of Restoring Vintage Bicycles; CPA/Founder of Wilken & Company, P.C., CPAs

1951 The Bicycle Magazine U.K.

I recently purchased two editions of The Bicycle, a U.K. publication.  Both date to 1951. The May 30th publication, pictured above is the “Northern Edition”, and features cycling tours of Exmoor in Somerset, as well as racing results from the myriad competitions occurring at that time in Northern England.  The cover page above shows two riders on their Phillips Reynolds 531 bikes with Dunlop tires and “racing” hubs.

In perusing both editions I discovered that this photography column was a regular feature.  Written by Frank Newbold, these columns discuss a variety of basic but perplexing concepts for the film photographer of the day.  Using exposure meters correctly is covered in the 5/30/51 edition, and depth of focus is covered in the 4/11/51 column.  The concepts presented here still hold today, even with our digital cameras, and I found the discussions a helpful review.

The advertisements are also especially interesting.  The page above features a Reynolds 531 Elswick step through frame, as well as the stunningly beautiful lugs from Hetchins.  These are the “Magnum Opus” lugs used for the highest quality machine that would be offered at the time.  In addition, there’s an ad for a “lightweight” camping stove called The Monitor which was fueled by paraffin and weighed under 2 lbs.

The April 11, 1951 edition’s front page shows a rider on a Reynolds 531 BSA model.  Clearly Reynolds 531 was the gold standard of the day, as it is now.

This Sturmey Archer ad is for an FM 4 speed model.  This was a close ratio model used by racers.  It’s interesting to note that the AW model, which is considered the most useful for all-around cycling, is not even mentioned in the above advertisement.

Here are some advert pages from the April 1951 edition. The Jack Taylor ad features a step through frame.  I’ve noted from these ads that the drive train was not specified.  Instead, you would select whether you wanted an internal hub, fixed/free, or a derailleur gear model.  This practice continued well into the 1970’s, but is not an option today for new bicycles.  You’ll also see the advert for the gorgeous Resilion cantilevers  – probably the most elegant brake design I’ve seen.  These cantilevers were clamped to the stays, so it didn’t matter whether you had braze-ons or not.  You could use them on any bike.

I’ve found great pleasure and knowledge in vintage cycling publications.  I am continually amazed to see that cycling lore from days gone by still holds today.  The above back page advert shows a Miller dynamo system.  While dynamos have now migrated to hubs, the concepts remain unchanged.  And that’s true for much of the cycling industry.

Eccentrics in Cycling

1958 Eccentric bottom bracket on Rene Herse Tandem – Daniel Rebour drawing.

Eccentric bottom bracket on 1977 Jack Taylor tandem

As part of restoring my 1977 Jack Taylor tandem, I needed to rebuild the eccentric bottom bracket and set it up correctly.  There’s been a bit of a learning curve, since I haven’t previously restored a vintage tandem.

The use of an eccentric appears to first date to the steam engine era, to optimize the efficiency of a rotating shaft.  And eccentric bicycle components have been around for over 100 years.  Yet, it can feel foreign, and daunting to work on a bike that features this technology.

What is an eccentric?  The official definition from Wikipedia is:  “in mechanical engineering, an eccentric is a circular disk (eccentric sheave) solidly fixed to a rotating axle with its centre offset from that of the axle (hence the word “eccentric”, out of the centre).”  The above photo depicts an eccentric pedal design introduced in 1903. 

Here’s a dual eccentric bottom bracket that can alter the gearing ratio at the crankset, also introduced in 1903.

Fred DeLong’s experimental fork dropouts

Fred Delong even spec’d a bike that had offset fork dropouts, to enable him to quickly change his bike’s rake and trail characteristics.  Although not technically an eccentric, this dropout design allowed him to choose when to optimize for trail and wheel flop, as shown in the table above.  A similar result could be achieved with an eccentric front hub.  Currently, eccentric hubs are limited in application to the rear where they are used to adjust chain tension on fixed gear bikes.

My Jack Taylor tandem features an eccentric bottom bracket that is similar in design to the 1958 model depicted at the top of this post. The threaded portion features a T.A. spindle and cups. There is a single hole drilled into the offset section.  Newer eccentric bottom brackets have multiple holes drilled, so that a pin spanner can be used to ease the adjustment process.  I can’t quite make out the lettering on this model – does it say “Rogers”?

I had wanted to rebuild the bottom bracket while it was off the bike – one of the benefits of this design.  However, when it came time to install the rebuilt BB back into the shell, the fit was very tight and needed to be accomplished with a mallet.  Not wanting to damage the cups or bearings, I disassembled it and then rebuilt it again once installed in the shell.  But, when I did so I ended up positioning the spindle toward the front rather than the rear of the bike.  That’s not what you want, since the whole idea of this design is to allow one to move the spindle toward the front as the timing chain stretches with wear.

I made this video showing how to adjust the eccentric bottom bracket on a model where only one hole is drilled. After loosening the bolts in the shell, and using an Allen wrench inserted into the hole and then leveraging that with a heavy duty screwdriver against the spindle, you can get the eccentric positioned where you want it to be.  It’s clear to me now that overhauling a tandem is much more involved than a typical restoration.  Still, it’s been fun to learn new techniques.  I’m looking forward to the rest of the process.

Drum Brake Overhaul – Jack Taylor Tandem

Drum brakes get a bad rap because they aren’t very effective when compared to rim brakes.  But, on vintage tandems, drum brakes are added to assist with rim braking. My 1977 Jack Taylor tandem features this front brake augmentation, which helps to keep the heavier and more powerful tandem bike’s front rim from overheating on descents.  An overheated rim can blow off a tire – not a good thing!

To accomplish this dual braking, the Mafac lever is modified to accept two cables – one for the cantilevers, and one for the drum brakes.

This bike’s drum brake hub is a cup and cone Maxi Car model featuring black dust caps.  The drum and pads were filthy dirty, and one pad had separated from the brake arms.  The pads were covered in grime and were glazed, but did have more than 2mm of depth meaning that they were still usable.

I cleaned and sanded the drum and the pads to smooth out the contact surface and remove the glazing. I also re-glued the separated pad to its arm, using an epoxy resin rated for extreme high heat (a JB weld product).  I clamped that with a C clamp and let it sit for about a week.  Then, it was time for reassembly.  Fortunately, when I disassembled the hub I took a series of photos at each stage.  I referred to this series of photos while I put the drum brake hub back together.

But, I also consulted Glenn’s Complete Bicycle Manual for an overview of the process.  This manual is the only vintage repair manual that addresses the overhaul of drum brakes in adequate detail.  Above are a few pages which illustrate the process.  In total, the manual contains 5 full pages dedicated to drum brake overhauls.  There are locknuts, spacers and nuts which need to be in the right place in order for the brake to operate as intended, which is why it’s so important to document the disassembly process.

This model of drum brake features only one spring, whereas some contain two springs.  When the arm is engaged, the spring opens and moves the pads outward toward the drum via a cam mechanism.

Once the hub was reassembled I put the wheel up into the dropouts and attached the fixed arm to the fork blade, using the original “88” rated bolt.  This designation signifies its tensile strength.

Having reinstalled the fork and headset, it was now time to install the stem so that I could set up the bars and brake levers.  I had noticed when working on the fork adjustment that there was no hanger for the cantilevers, and that’s when I remembered that this bike has a cable stop drilled on the stem.  I ended up having to gently re-tap the threads for the barrel adjuster, but the Milremo stem cleaned up beautifully after polishing it with Nevr Dull.

The next step was to set up the cable, and for that I needed to make sure I understood how the hardware should be positioned into the brake arm.

The original hardware’s end cap could not be reused because the cable would not come out, so I found a replacement and began the process of setting up cable tension.  It took several trial and error passes to get the cable tension correct so that the pads did not contact the drum when not engaged, but contacted the drum adequately when engaged without bottoming out the brake lever.

I made this short video showing the operation of the brake.  All looks good, and now it’s time to move on to the installation of the cantilevers. After that, I’ll continue on to the drive train, having previously cleaned, polished, and waxed the frame.  I’m glad to be making progress on this wonderful vintage machine.