Tag Archives: Maxi-car hubs

Drum Brake Overhaul – Jack Taylor Tandem

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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.

 

1977 Jack Taylor Tandem Restoration- the Beginning

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Mafac hood with dual cables

I’ve been waiting to get in the right frame of mind to begin restoration of a 1977 Jack Taylor Tandem that I had shipped from England back in 2012.  Clearly, I’ve been waiting quite a while, but during that time I have corresponded with the original owner’s son, who has provided valuable information about the bike’s history as well as a few family photos of the tandem’s exploits.

Jack Taylor frame at bottom left

I also needed more shop space to enable me to use two stands to aid with disassembly.  That finally happened last Fall, and I now have not only more shop space, but additional bike storage space as well, all in one location.

So I was finally able to remove the components to begin the process of bringing this tandem back to its original glory.  I had already removed the 650b Maxi-Car wheelset and worked on getting the wheels back in order.

I still need to re-glue one of the brake shoes in the front drum hub, but the rear wheel has been overhauled and adjusted.

Jack Taylor frames are built with Reynolds 531 tubing.  The specs for each Reynolds tubeset will vary based on customer request and on the particular application.  A serial number is stamped on the rear drop-out and the steerer tube.  You can see the matching numbers in the above photo – 7183 – indicating this is a probably a 1977 frame, based on the helpful chart provided by Joel Metz at his blackbirdsf.org site.  This chart was developed from information provided by Mark Lawrence, who happens to be the individual I purchased this tandem from.  He sold the bike on behalf of the original owners.  Mark was a long-time friend of the Taylor brothers.

Tandems differ from regular bikes in a number of ways.  There are naturally two bottom brackets, one of which is an eccentric, which aids in adjusting the timing chain so that that both sets of cranks are positioned at the same angle on the spindle, and so that chain tension is properly maintained.  The matching crank arm position is important for cornering, as you want both crank arms upright when descending at speed while leaning over.  Both bottom brackets are T.A. models, and the threaded eccentric appears to say “Rogers”.  It taps out of the frame after loosening the bolts.  Adjustment is made by loosening the bolts, twisting the eccentric to the desired position, and re-tightening.

The components on this tandem indicate that it was the Super Touring Deluxe model, spec’d with Mafac Tandem cantilever brake calipers (plus a Maxi drum brake up front), Stronglight headset, Campagnolo derailleurs and shifters, Campagnolo drop-outs, SunTour Perfect 5 speed freewheel, T. A. cranksets, plus Maxi-Car 650b wheels.

1977 Jack Taylor Tandem with kiddie crank and trail-a-bike

Four cranksets was one more than expected.  Upon corresponding with the son of the original owners, I learned that this was needed to set up the “kiddie-crank” for the young stoker.  His sister contributed to the effort on her trail-a-bike.

As originally purchased 1977 Jack Taylor Tandem

As I’ve researched the history of Jack Taylor Cycles I’ve come across a few sites I hadn’t accessed before.  One of these is the Stockton-on-Tees History site, which has several wonderful posts regarding the history of the “works” building and of the Taylor brother’s exploits:

Jack Taylor Cycles

Jack Taylor Cycle Maker

While the restoration process may take some time, I’m hopeful about the result.  This is a machine worth preserving.

Overhauling Maxi-Car Hubs, Part 3 (whew!)

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My Maxi-Car hub overhaul experience has spanned many weeks now.  When I left off in Part 2, I was working on a set of Maxi-Car hubs from a 1977 Jack Taylor tandem.  After running into some issues with those hubs, I went back to the older hubset that I was using as my platform for learning the process.  Those hubs were soaking in penetrant for several weeks.  I had been unable to drop the axle through the hub by striking it with my mallet.  Several readers suggested using a regular hammer with a piece of brass to protect the axle, or a copper or brass hammer.

That turned out to be good advice.  But, I didn’t have a copper hammer or a piece of brass.  And, my local hardware store doesn’t carry copper or brass hammers, so I purchased a much heavier dead blow rubber mallet and finally got the axle of the rear rub to drop down.  The top photo above shows what you see when this happens.  The axle carries with it the two outer seals, plus the bearing set and inner race.  The outer races are permanently attached to the hub and do not need to be removed for the overhaul process.  The hubs and parts were very dirty so I soaked everything in alcohol and then used a pipe cleaner to get at the nooks and crannies inside the bearing rings.

Bearing ring before cleaning

Inner races looking good

Once I had the parts cleaned it was time to begin the lubrication, assembly and adjustment process.

Since the hubs are sealed, I operated on the theory that it would not be a good idea to heavily grease the races and bearings.  The grease has no place to go in a sealed system, so I modestly applied grease, as shown above, using Phil’s waterproof bearing grease.

Now comes time for the assembly and adjustment process.  The above two pages from Yellow Jersey’s Maxi-Car tech manual are the most important resources for the process.  The tech manual was translated from the original French, and so there is the potential for lost meanings and nuances.  The assembly process proceeds in this order:

1.  Assemble the non-adjustable end of the axle with the flat washer and the cambered washers, the bearing cage, and the inner race.  Then insert this into the hub.  On a rear wheel, the fixed end of the axle always corresponds to the freewheel side of the hub.

2.  Put the fixed end of the axle into the hub axle vise.  Now assemble the adjustable side’s inner race, bearing cage, and two washers in the same order as disassembled (See diagram above).  You will note that the inner race will not fully seat onto the axle.

3.  Screw on the adjustment nut until the inner race begins to move downward over the axle, leaving a slight amount of free-play.  Unlike a regular cup and cone adjustment, this is a one-way venture, and if you over tighten the nut, as I did the first time I tried this, you’ll have to disassemble everything and start over.  But, practice makes perfect.  I slowly screwed down the adjustment nut until I felt approximately the same amount of free-play as I would want in a cup and cone hub with a quick release axle.  The instructions say to “take the wheel by the rim and try to move it up and down”.  You want “a little play”, according to the tech manual.

4.  Reassemble the lockring, outer nut and dustcap onto the adjustable end. Lock the nuts against each other.

5.  Now flip the hub over and do the same thing on the fixed end.

The hub should spin freely but without excessive side to side play when mounted in the dropouts.  I ended up doing the adjustment twice because my initial attempt was too tight.  The above video shows the hub spinning smoothly after the final adjustment.

This undertaking was challenging but also rewarding, and I’m looking forward now to working on the Maxi-Car hubs that are part on the 1980’s custom Meral that landed in my shop last Summer.  Stay tuned!