About Nola Wilken

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

Setting up Centerpull Brakes

Center pull brakes are often standard equipment on vintage bicycles. Their design can allow more clearance for fenders and wide tires, and based on where the pivots reside, they may have more mechanical advantage than standard sidepull brake calipers.

But, centerpull brakes are sometimes viewed as more challenging to set up than side pull brake calipers.  How long should the straddle cable be?  How close should you set the brake pads to the rim? What is the ideal angle for the straddle cables?  How much torque should go on the mounting bolt?  What about lubrication of the pivot points and cables?  Should the straddle cable be thick or thin?  And, most important, how can you eliminate brake squeal on these often very noisy calipers.

Brazed on centerpulls – a 1978 Centurion Pro Tour

For over twenty years I cycled on a bike that had the best centerpulls you could find – brazed on centerpulls were standard equipment on my 1976 Centurion Pro Tour.  While this advantage went unnoticed by me in my youth (I had nothing to compare this to), I have definitely noted the extra care and adjustments needed to the bikes I currently ride which feature center pull brakes, but which are not brazed on to the frame.  The above photo shows brazed on Dia Compe centerpulls on a 1978 example of a Centurion Pro Tour.

1953 Follis branded Jeay brakes

1947 Peugeot with Jeay centerpull brakes

Brazed on centerpulls have been around for a long time.  The above examples show Jeay centerpulls on a 1947 Peugeot, and a more custom example from Follis on a 1953 frame.

If you are ordering a custom bicycle, you can most definitely specify for this braze-on feature.  Using the brazed on version of centerpull brakes keeps the brakes centered, and undoubtedly improves the overall performance of the brake.

What is the best way to set up centerpull brakes?  Sheldon Brown offers some guidance, as well as Park Tools.  But the instructions on these sites do not address some puzzling issues such as the proper length and angle for the straddle cable and the proper distance of the pads to the rim. Nor is the cable width and pivoting characteristics of the straddle cable discussed (a la Mafac).

For the question regarding the ideal pad distance to the rims, I can turn to both my own personal experience, as well as to one of my favorite resources – Glenn’s New Complete Bicycle Manual. The distance to set the pads to the rim is recommended at 1/8 inch, according to “Dr. Coles” (aka “Dr. Glenn” – the author whose white coat visage inspired my affectionate homage). That’s about 3 mm.  Seems about right to me, based on my many decades of cycling with centerpull brakes.

Rebour drawing of Mafac centerpulls with extra long straddle cable

The length and width of the straddle cable is another important element to consider when setting up these brakes.  For Dia Compe and other non-Mafac centerpulls, it may appear that you have no choice in selecting the straddle cable, but these cables actually come in all different lengths, not just the one included with whatever caliper you are working with.  The angle and width of the cables can impact the performance of the brakes.  More flexible and moveable cables (a la Mafac and Compass) will provide better performance. One of the nice features of Mafac brakes is that the straddle cable is actually a shifter cable cut short, so it is easy to replace and adjust these straddle cables for Mafac brakes, at will.

The above Daniel Rebour drawing shows a custom frame with unusual braze-ons for the rear centerpull calipers, resulting in a very long straddle cable.  In my experience, the length of the straddle cable is not so important as its angle – a wider angle at the yoke being more advantageous.  The angle will decrease as the brake lever is applied.  Also, pads should be set parallel to the rims, and with no upward or downward angle for best results (unlike some cantis which may need a slightly upward angle).

For Mafac enthusiasts, one issue is the flex characteristics of the fork and seatpost hangers.  These hangers are not very stiff, so that when braking pressure is applied, the hanger can flex significantly, reducing the performance of the brake and providing for a “mushy” feel.  Because of this, I have sometimes replaced the Mafac hangers with more robust hangers on my bikes with centerpull brakes, and with good results.  The above photos show the Mafac hangers.

V-O brake pad holders with toe in adjustment.

V-O smooth post pads – non squeal variety.

Brake pads are important to any brake set-up. While Kool Stop does make Mafac replacement pads – both in orange and black compounds, I have found that I prefer using Velo-Orange pads for my centerpull brakes.  They are quieter and yet perform equally well.  I usually lubricate all the pivot points on any centerpull brake I am setting up, as well as lubricating the straddle cable and yoke.  It’s critical to check your cables and the bolts securing them for wear and proper torque on a routine basis, and if any cables show degradation, replace them immediately.  You never want to apply the front brake, only to have it fail. That’s 70% of your stopping power.

Mid Century Mercier Meca Dural Restoration – a Brief Test Ride

Mid Century Mercier Meca Dural – Autumn 2017

MId Century Mercier Meca Dural – Winter 2017

Today I ventured out for a test ride on this Mid-Century Mercier Meca Dural – a bike which had been incorrectly modified when I acquired it last fall.  I spent the winter restoring it and replacing many of the incorrect and missing components. But, I hadn’t had time in my schedule to get the bike out on the road for a test ride until now.

Vintage Rigid Chain Guard

Carradice Long Flap saddlebag – stuffed with all the possible tools need for a first test ride.

Unfortunately, I chose a bad moment to take the bike out to Sauvie Island – one of my favorite low key cycling jaunts.  It’s the weekend before Halloween, which I realized only too late upon arriving at the Sauvie Island parking lot where cyclists normally unload their bikes for a journey around the bucolic beauty of this little island treasure near Portland.  That meant hordes of cars heading to the Pumpkin Patch – a place where kids can enjoy all kinds of thrilling Halloween activities.  There are no shoulders on the flat roads of Sauvie Island, so cyclists who venture there rely upon the good will of the Island’s drivers, which is usually just fine.  Today, however, was not the right day to take an untested bike into this environment, and that realization dawned on me after just a few minutes of cycling on the Meca Dural’s duralumin frame.

Original alloy Guidonnet Levers.

The ride I cut short to avoid the stress of a steady stream of vans and SUVs passing too close provided some valuable information.  One thing I learned was that these original guidonnet aluminum alloy levers have an unusually long reach, so if you need to brake suddenly and don’t have gigantic hands, you may not stop as quickly as you would like.

C.M. long reach calipers.

The C.M. long reach brake calipers have quite a bit of flex under hard braking.  This caused the front brake to jump a bit when I attempted to stop suddenly.  That may simply mean that the brake mounting bolts need a bit more torque – so that’s an issue to sort out.

Chain guard mounting hardware.

I also discovered that the lovely vintage Rigid chain guard which I had installed using a combination of new and vintage mounting hardware needed adjustment, as the chain rubbed against the guard in the lowest gear. Fortunately, this mounting hardware makes it very easy to adjust the position of the chain guard by turning the nuts on the long connecting bolts.

Vintage Simplex Grand Tourisme rear derailleur.

The 3 speed freewheel is mated to a 46 tooth Louis Verot chainring on Stronglight 49d crank arms.  The small cogs make for high gearing, which was almost too high even on the totally flat roads of Sauvie Island.  One solution will be to locate a vintage french threaded freewheel with larger cogs.  The bell crank actuated Simplex derailleur worked perfectly and can definitely handle larger-toothed cogs. Shifting was straightforward, with no noticeable over-shifting required. Since I didn’t have the original chain, I had guessed at the chain length.

The ride quality overall was comfortable. I attribute this primarily to these wonderfully preserved vintage Mavic 650b rims and the new Panasonic tires, inflated to fairly low pressures, as well as to the flex characteristics of the duralumin frame.  This bicycle’s frame design doesn’t include an extra set of mixte stays extending to the rear drop out.  Initially, I experienced a bit of a wobbly feel at the front end, which would likely become a non-issue once a rider gets this bike underway for a few miles.

Meca Dural ornate aluminum lugs joined by internal steel expanders. Kitty is optional equipment.

After this brief ride I know what is needed to make the bike more useful and reliable.  And, I didn’t worry about the Meca Dural aluminum tubes – they performed no differently than any steel framed bike I have ridden.  The bike as pictured weighs 24 lbs – very impressive considering the full fenders, chain guard, and dynamo lighting system.  The next time I ride this bike, I hope to have a bit longer and more enjoyable ride.

A Velo-Orange Shipment

I order components from a variety of sources, but one of my favorite suppliers is Velo-Orange.  Even though its founder, Chris Kulcaycki, sold the company earlier this year to two of his long time employees, I haven’t noted any negative impacts on the quality and variety of products offered.  I think the company is well positioned amongst its competitors, namely Compass Bicycles – Boulder Bicycle – Rene Herse (all owned by Compass Bicycles/Jan Heine), Rivendell (Grant Peterson), and Harris Cyclery (Sheldon Brown’s shop), as a purveyor and innovator of bicycle frames and components for cycling enthusiasts, and especially for those who appreciate the quality and reliability of steel frames, comfortable, wide tires, and retro-inspired components.

My haul today included some of the parts needed to complete the 650b/city bike conversion for the early 1980’s Meral Randonneur bike I recently purchased.  In my box of goodies was a full length chain guard, Velox rim strips (more on that later), V-O thumb shifter mounts (competing with Pauls’ Thumbies), Tektro brake levers, and a new KMC 8 speed chain.

I also ordered an extra 8 speed chain (you can never have enough chains), as well as my favorite brake pads:  V-O’s non-squeal smooth post pads, which work really well with Mafac long reach brakes.

I also use these bake pads on any bike with cantilevers – they really are almost 100% squeal proof and provide excellent stopping power.

But what prompted this order was the extraordinarily bizarre experience I had attempting to mount a set of Grand Bois 32 mm 650b tires to the Velocity A23 650b wheelset I had purchased from Harris Cyclery for $289.  Yes, that was the price for both wheels, which feature Shimano Tiagra hubs.  Well, you get what you pay for.  I purchased these wheels as a placeholder to see if a 650b conversion would really work for this bike, so that is why I went with the cheapest offering out there.  The downside was discovering the the holes drilled in this narrow rim end up partially on the upper edge inside the rim where the tire’s beads need to mount.  Installing the necessary narrow rim strip meant not covering these very sharp edged holes completely, which I knew would lead to flats and blow-outs later on.  I tried installing a wider strip, but that interfered with the Grand Bois tires’ beads.  Many swear words ensued at this point.  Finally I took to the internet to see who else had experienced this problem.  Turns out – everyone.  The best advice I read was to use three narrow rims strips on each rim, carefully positioned to cover the holes without interfering with tire mounting.  We will see how that goes (subsequent blog post forthcoming!).

Meanwhile, I am looking forward to setting up the other components, such as these very elegant Tektro brake levers.  Using 32 mm tires means that I will be able to re-install the lovely custom stainless steel Meral fenders.  It will also be interesting to try out the full length chain guard for this build which I envision with a single chain ring up front, as well as to experiment with V-O’s version of Paul’s thumbies.  Stay tuned.