Wednesday, April 9, 2014

Seals & Bearings & Hubs, Oh My!

For me, working on bikes is part of the fun of cycling. Although I used to be pretty good at it back in the 60's (I did all my own maintenance and worked in a bike shop), the evolution of technology and my lack of recent practice have set me back. In fact, one factor contributing to my non-cycling between 1979 and 2008, especially towards the end of that period, was that my Bianchi Specialissima had accumulated enough problems to be unridable, and fixing it just never happened. The decision I made that cut the Gordian Knot was to take my Bianchi to Daniel Boone Cycles and have them fix it. The cost to do that was high, but the net result was that I was riding again. In the end, my Bianchi turned out to be too high maintenance to keep me riding, so I supplemented it with a Surly Crosscheck, an extremely reliable and versatile bicycle. However, I have tried to keep my Bianchi running and I enjoy riding it when I can. This post details recent trials and tribulations pursuing that goal.

My Bianchi Specialissima after the work described in this post. Some time ago I (temporarily) replaced the Campagnolo toe-clip pedals with inexpensive SPD-compatible clipless pedals on sale at Harris Cyclery.

The first reliability issue I had with the Bianchi were its sew-up tires. Shortly after I started riding, I was out on a ride and had a flat. I was carrying a spare which I put on, but when I got home I realized the spare had slipped on the rim causing it to become abraded, ruining the tire. A mistake I had made was that I had not pre-applied glue the spare. Glue for sew-ups stays tacky for a long time so if there is "dried" glue on the tire and "dried" glue on the rim, some adhesion will occur even in the absence of fresh glue. (Fresh glue needs to dry for 24 hours before being used, so re-gluing on the road is not considered an option.) Whether pre-gluing the spare would have been enough to prevent the problem and allow for a safe ride home, I don't know. I do know that between 1965 and 1979 I rode exclusively on sew-ups, including on multi-day tours, and must have dealt with the issue of tire changes on the road somehow, but I can't remember how. When I researched the issue on the web, the answers I found were all more or less "you can't do that." Before I had a chance to figure this out, I had an accident that ruined my back rim, preventing me from cycling for four months until I acquired my Surly.

My bent sew-up rim with the point of damage circled in red. It has a tire on it because I am currently using this old rim to stretch new sew-up tires, a necessary step before mounting them.

I still wanted to ride my Bianchi, so a few months after purchasing the Surly, I purchased inexpensive clincher wheels from Harris Cyclery. Although these made my Bianchi ridable for almost two years, I had two problems with them, one immediately, a second one a year and a half ago. When I ordered the wheels, I knew they were not quite the right size, they were made for a rear drop-out spacing of 126 mm instead of the 120 mm of my Bianchi, but Harris Cyclery said that this wider back wheel should still fit into my frame, and it did. However, because of the difference in size, the rear gears were shifted away from the derailleur by 6 mm. This required a derailleur readjustment which was not a problem, but as a result, my very old Campagnolo Gran Sport derailleur which previously could just barely accommodate a 26 tooth rear sprocket could now not quite accommodate a 26 tooth rear sprocket, meaning I had lost my lowest gear on a bike which already suffered from a lack of low gears. Besides the practical consequence, I found this esthetically unpleasing, just as I found the stretching of the frame needed to get the wheel in unpleasing, and promised myself that I would fix this some day by cutting 6 mm off the rear axle and spacers and re-centering the wheel. In the mean time, I had found some old sew-up rims on E-Bay and planned to repair my broken sew-up rear wheel which I could use while working on the clincher wheels. While waiting to get around to that, I bent the clincher rim on the front wheel, taking my Bianchi out of service.

The good news is I just now succeeded in building my first wheel in 40 years - once again I have two functional sew-up wheels for my Bianchi. However, there are two problems. The first is the problem of changing sew-ups on the road, discussed above. I am carrying a pre-glued spare and we shall see if that works. The second problem is freewheels and gear ratios. I own two freewheels that fit my Bianchi. The one I had been using had cogs varying between 14 and 26 teeth, the one that came with my Bianchi, that I had not used since 1970, has cogs varying between 14 and 20 teeth, a ridiculously narrow and ridiculously high range of gears. When I went from sew-ups to clinchers, I transferred the 14-26 tooth cluster. When I finished repairing my rear sew-up wheel, I went to do the reverse. To do that, I needed to remove the nuts from the axle because they get in the way of the freewheel removal tool. I don't know how the experts deal with this, but I used the technique we always used back in the 60s; I put a wrench on the nuts on either side of the wheel and turned them counter-clockwise. This causes the nut on one side or the other to come off. If the nut on the wrong side comes off, no problem, just pull the axle out, grab it with pliers in the middle (where there are no threads to be damaged) and use a wrench take the nut off the other side. Removing the nuts would also give me the opportunity to shorten the axle and spacers to change the wheel from 126 mm to 120 mm. As it happened, the nuts on the wrong side came off. When I went to take the axle out, it wouldn't budge. Foiled again by the evolution in bicycle technology! The new wheels use sealed, cartridge bearings (as does my Surly.) These bearings are wonderful, they run smooth, require little adjustment and no maintenance. After very long use, when they finally wear out, you simply replace the whole unit. However, part of the way they are held in place is by collars on the axle which prevent the axle from being removed without removing the bearings, an action which is likely to destroy the bearings (and is normally only done when you are replacing them.) Until I figure out how to solve this, the only way to use my sew-up wheels (my only functional wheels at present) is with the ridiculous 14-20 tooth freewheel.

Obviously I am a lousy photographer, after several attempts this is the best picture I got of the very narrow 14-20 tooth freewheel on my Bianchi.

How does it ride?

Gluing on sew-up tires is a bit of a production. After reading several peoples' opinions on the Web, I settled on applying two pre-coats of glue to the rim, one pre-coat to the tire, and then the final coat when I mount the tire. Each coat of glue requires 24 hours to dry, so it was three days before I could try the bike. The first day I rode it I just rode around the block, adjusting the derailleurs and fixing any issues that arose. My first impression was of a very uncomfortable bicycle! Part of that is that it had been a year and a half since I had ridden the Bianchi and I had gotten very used to the Surly. The handlebars on the Bianchi are narrower and it handles very different; by comparison to the Surly, the Bianchi feels squirrelly. A second issue was the saddle. Both the Surly and the Bianchi are equipped with Brooks B17 saddles, but the saddle on the Surly is well broken in, whereas the saddle on the Bianchi only has about 50 miles on it and is hard as a rock.

My Bianchi parked in front of my Surly. Overall, the dimensions look fairly similar to my eye. The glaring difference is the height of the handlebars - the tops of the Bianchi handlebars almost line up with the bottoms of the Surly handlebars.

A third issue has to do with a change I made to the Surly over a year ago; I added an extender to raise the handlebars by 3 inches. If you look carefully at the picture above, you can see the extender on the Surly in the rear and how it raises the handlebars. When riding the Bianchi, the handlebars feel very low and the distance between the seat and the handlebars feels short. (When I first started riding the Surly, the distance between the seat and handlebars felt too long.) Looking at the picture, I can't see that the seat to handlebar distance is really different but what is crystal clear is how much lower the Bianchi handlebars are than those on the Surly.

The proof is in the pudding. Having made sure the Bianchi was working OK, the next day I rode it rather than my Surly on my daily MAF test ride. The heart rate monitor I am currently using is independent of the bicycle so didn't need to be moved. It is easy to move my Garmin Edge 500 Cycle Computer (speedometer) from bike to bike, but moving the associated cadence sensor is harder so I did not do that. I have previously noted that, although the Bianchi feels faster than the Surly, when I compare the speed I measure on standard rides on the the two bikes, the actual speeds seem about the same. Because of day to day variation in MAF test results, I can neither confirm nor deny this assertion based on one ride, but I have no reason to change my opinion on this point. The saddle was definitely hard, but was tolerable for 90 minutes of riding. Since it takes 500 miles to break in a Brooks saddle, I am now 70 miles down, 430 miles to go. And, as expected, the gears were ridiculous; I did the entire ride in my lowest gear (61 inches) and the unavailability of lower gears noticeably compromised by cool down ride home. If I keep this bike as a show bike, it certainly is rideable as-is. However, if I want to use it as an alternative to the Surly for longer rides, changes will have to be made.

Future Work

To make my Bianchi useful for serious riding, I feel like I need to do three things; raise the handlebars, lower the gears, and put on clincher tires. 

To raise the handlebars, I could either purchase a stem extender like I did for the Surly or purchase a taller stem:

On the left, a stem extender available from Rivendell Bicycle Works.
On the right, taller stems available from Harris Cyclery.

The taller stem would certainly be more elegant, but it is also more expensive and might not result in handlebars that are as high (or high enough.) I am still weighing these two options.

I have two ideas for how to put clincher tires on my Bianchi. The obvious one is to repair the clincher wheels I already have. However, I am having trouble fixing the bent front rim. As per Sheldon Brown's website, I do not plan to use just spoke tension to fix it because that would result in an unacceptable variation in tension spoke to spoke. Rather, I am trying to bend it back roughly into shape before fine tuning it with the spokes. However, I have been unable to do so, it just won't budge. If I give up and purchase a new rim, then I have to consider the time it would take to rebuild the wheel and I would still have the problem of the back wheel having a 126 mm axle spacing rather than 120 mm and the impact thereof on the gears (discussed above). I will probably keep fussing with these wheels just to amuse myself, but I think there is no guarantee they can be made to be satisfactory.

My second idea for how to put clincher tires on my Bianchi is to cannibalize some parts from my wife's old, unused Gitane. The 27x1¼" (ISO 630) wheels on that bike won't fit the Bianchi, but the hubs from those wheels will. In particular, the rear hub has a 120 mm width like my Bianchi. If I remove the old rim and spokes and replace them with 700C (ISO 622) rims and spokes of the appropriate length, the resulting wheels should fit perfectly. However, freewheels are not interchangeable between the hubs on the Bianchi and the hubs on the Gitane; the Gitane uses French threads and the Bianchi English, so I would have to use the Gitane freewheel. The freewheel on the Gitane has cogs varying from 14 to 32, a much larger range than my old Gran Sport derailleur could handle. It is possible, however, that the SunTour derailleur from the Gitane would work on the Bianchi. If so, that would not only provide me with clincher wheels, but acceptably low gears. I had previously considered this solution but had balked due to the bastardization of my Bianchi this would entail. However, as I gain experience and become more comfortable with bike mechanics, such bastardization becomes less permanent. With relatively modest effort, I could restore the Bianchi to its original configuration any time I wished, especially now that its original sew-up wheels are functional. Stay tuned to learn the fate of my long suffering Bianchi Specialissima.

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