More Clearance with Single Pivot Sidepull Brakes

Shimano 105 dual pivot sidepulls

I’ve been wanting to mount some wider and more comfortable tires on my 1990’s Terry Symmetry, which was built during the sad era of zero brake clearance for wider tires.  Even after switching from the 650c rims which the bike was designed for, down to 26″ 559s, I had no room for fenders with the 32 cm (actually measuring at 28mm on my rims) Paselas I was using.  But, since I mounted the fenders without going underneath the fork crown and brake bridge, I wondered if I could use some wider tires which might provide more comfort than the competent but harsh riding Paselas I’ve been using.

So, I purchased a set of Schwalbe Kojak 26 x 1.35 tires.  Since, there are almost no tire options available for road bikes running 26 inch tires, and while I usually do not care for Schwalbe’s offerings, I was left with these Kojaks as the only choice as an alternative to the Panaracer Paselas.  The Elk Pass tires offered by Rene Herse Cycles that I had previously tried proved to be so flat prone that I could no longer tolerate them.  When I mounted the Kojaks, which were very difficult to install on my rims, the Shimano 105 dual pivot brakes contacted the tires, so I knew I was going to have to figure out a different brake option that would provide better clearance.

Dura Ace single pivot sidepulls

Fortunately, I am not the first cyclist to crave wider tires on a road bike, and to push the limits of tire clearance.  There are many forum posts and websites devoted to finding solutions to this problem.  A number of possible solutions to the tire clearance problem exist, but the clearest path involved choosing single pivot sidepulls, which can generally offer better tire clearance than their dual pivot counterparts.  While dual pivots are super easy to set up, I’ve never been put off by single pivot brakes, except for: see below!

Weinmann 600 sidepulls

First off, I tried these Weinmann 600 brake calipers, which were sitting in a NOS box in my parts bin.  Handling these calipers and using their hardware proved shocking:  these brakes come with very low quality bolts, and some of the nuts had been cross threaded.  So, this low quality brakeset has been set aside.

Dura Ace Centerpulls

But, then I thought:  what about switching to centerpull brakes?  That would mean installing front and rear hangers, but could be an option to consider.  I dry mounted these first generation Dura Ace centerpulls but they actually proved to have less clearance than the Shimano 105s.

So, I tried out a number of different options ranging from the very nice Dia Compe BRS 200s (which didn’t have quite enough brake reach on the rear brake), to these oddball Dia Compe AC 600s (pictured last), which feature a strange offset angle for cable routing, apparently to reduce wind resistance, which is nothing short of ridiculous.  And, they have no quick release mechanism, a must for any brake caliper.

Rear caliper installed backwards

Front caliper with much more clearance.

Finally, I settled on a set of Shimano 600 single pivot sidepulls which are actually the matched set to the Shimano crankset I’m using on this Terry.  But, there were several problems to deal with.  There as less clearance in the rear than in front, so I mounted the rear brake backwards, which provided a few more millimeters of clearance.  Since this bike is designed for recessed brakes, it was also necessary to deal with the too wide opening for the nutted bolt.

Bikes designed for recessed brakes should not use nutted brakes unless care is taken to find a way to center the bolt inside the too wide opening.  In this case I used a leather washer which snugs into the recessed area, and then a larger washer to cover the area.

At the rear, clearance is good (relatively speaking) and performance seems okay for now.  Cable routing was odd, and I’ll think about a different solution, as there is some friction on the rear cable.

Here’s the bike with the Kojaks installed and the Shimano 600 single pivot brakes, with the rear brake installed “wrong” on the front of the seat stays.  We will see what happens when I take this bike out to test both the tires and the brakes.  I’m hoping for a more comfortable ride on the Kojaks and no decline in braking performance.  A long test ride will prove illuminating.

Compass Elk Pass vs. Panaracer Pasela, Part II

I promised to update my experience with these Compass Elk Pass tires after riding them for at least a few hundred miles.  Well, I’ve only put about 60 miles on these tires and I’ve already had my first flat.  That experience led to some other important realizations about these tires and the Schwalbe tubes I purchased with them from Compass Bicycles, a few months back.

Schwalbe tubes vs. Qtubes – 26″

To say that I am in a good mood this evening, after walking my bike home (rather than repairing the flat on the road – to be explained later), and then spending nearly two hours attempting to repair my flat rear tire at home would be incorrect.  First, though, I’ll talk about how these tires handled out on the road – before the flat.

These tires are lightweight – significantly so in comparison to the Pasela’s I had been using.  That reduction in weight, and the nature of the tire’s properties led to an enormous increase in my enjoyment of cycling on my Terry, which features 559’s front and rear.  The Elk Pass tires are fast and responsive under acceleration.  Accordingly, I found myself riding more aggressively than normal (but maybe that’s not such a good thing).  They are comfortable tires, and while narrower than their advertised width (32mm vs. actual 28 mm on my rims), the plush ride they provide feels like 38 mm tires or more.

The flat I had today occurred on pavement, and without any observed road detritus such as broken glass or thorns.  Within seconds of hearing a strange noise while climbing, my rear tire was flat.  This fortunately happened while I was cycling at  low speed.  The tire went TOTALLY flat – something that really can’t happen with regular clinchers that have more robust sidewalls.  The sidewalls on the Elk Pass tires are so supple that once the tube lost air, the tire had nothing to support it.  These tires are very much like a tubular in that respect.  Since I was only about a half mile from my house, I tried inflating the tube to see if I could simply coast home before the air made its way out.  No luck there.  The tube would not hold air at all.  So I removed my bags and walked the bike home with the rear wheel elevated, so as not to further damage the delicate sidewalls.

Once home, I examined the tire.  I couldn’t see any obvious cuts or sidewall cracks.  But, that’s not unusual when assessing a bicycle’s flat tire.  When dealing with flats, I normally unseat one side of the tire’s bead, take out the tube and then inflate the tube to determine where the puncture occurred.  That way, I can see where the tire is compromised, and if a projectile needs to be removed.  This tube went flat so quickly as I tried to inflate it that I ended up removing the tube from the wheel and closely examining it for the source of the puncture.

I hadn’t used the tubes that Compass had recommended for these tires – Schwalbe SV12 tubes which are wide and heavy in comparison to the Conti 650c tubes which have worked well for the 559 Paselas I had been using on this bike.  Since my existing tubes were good, I re-used them when installing the new Compass Elk Pass tires.  Upon close examination, I determined the source of the leak and then searched the tire for that location.

And, voila, here is the tiny little cut in the tread area.  Although very small, the cut bulged out once I had a new tube installed, so I booted this area with a folded dollar bill.  This experience made me want to mount the heavier and wider Shwalbe SV12 26″ tubes which are recommended (and I think this is due to the delicate nature of this tire’s construction), but after hours of trying to make these too large tubes fit into my tire and rim, I gave up (and remember that I recently mounted at 700c tube into this rim, with success).  The Compass recommended Schwalbe tubes are simply too large in diameter and too wide to enable them to work with this tire and on my Mavic X221 rims.  I tried dousing my hands, tires and tubes with some carcinogenic talcum powder to see if I could get these tubes to flatten out and not bunch up inside the tires.  NO SUCH LUCK.  And now, I am probably radioactive…