A few weeks ago, I was riding my Cannondale SuperSix on the hilly roads around Green Lane Reservoir and Pennsburg, PA, and
was getting out of the saddle to climb up a short, steep incline. All of a
sudden, I heard a nasty pop in the bottom bracket and found both of my
feet/pedals were now in the downward-stroke position – definitely not what a
crankset is supposed to look like!
For a couple months I had been failing in my
attempts to find the source of an annoying creaking sound in the bike's bottom bracket
area. I had tried cleaning/re-greasing/tightening processes on both the pedals
and the chainring bolts. I had also applied a bit of grease to all contact
points between the chainrings and crank spider.
With no positive results, I disassembled the
bottom bracket to clean and re-grease the spindle and contact points of the
edges of the sealed bearings. The creaking would go away for 30-40 miles of
riding, then gradually return. I had written in this blog about Cannondale’s
issues with their BB30 design and the insert this model bicycle required to
convert to Shimano’s Hollowtech system, and put a couple drops of penetrating
oil around the seams of the insert, just in case that might be a possible
problem area, but no dice!
Since Bikesport is a Cannondale dealer, I
thought the mechanics there might be familiar with this bottom bracket and its
difficulties. They knew about the BB30 glitches, but the insert that my bike
has should have negated those. One of the guys suggested a more viscous grease
that they use, which was red in color and created a gruesome bloody look when I
worked it onto the problem parts with my fingers.
Well, I certainly didn’t anticipate what
happened during the test ride – I just figured the sound would either disappear
or not. There must have been a hairline crack forming on the inside of the
spindle, as I definitely would have seen evidence of it forming during my initial
installation or the two other cleaning/greasing processes. I suppose the grease
had temporarily muffled the sound of the crack opening and closing as it
twisted inside the BB shell, until it finally snapped under the force of my
standing on the pedals.
I ordered a new Ultegra crankset and figured
that I might as well purchase a new bottom bracket to go with it. There was a
bit of a frustration period when the online store, ProBikeKit, misplaced my
order somehow. In the meantime, I was frequently riding my Colnago - I love that bike, but it
is significantly heavier and lacks a few teeth on the largest cassette cog,
which makes climbing that bit more difficult.
A few days ago, the new parts finally arrived, and I think the updated Ultegra cranks look great on the
Cannondale. Most importantly, the bike was whisper quiet during a 35-mile test
ride!
I fully expected to have Brendan’s Tommasini
finished a couple of weeks ago with photos of the completed project ready to
share. Unfortunately, the first-generation C-Record rear derailleur I ordered
from France had a worn-out cage return spring. I made contact with an eBay
seller from whom I’ve made purchases for other builds, and he had a “for parts”
Chorus derailleur from the same era. He sent me the return spring from that
derailleur, but I was disappointed to find that, although the spring was the
correct length and diameter, its tail pins were on the same side (see red
arrows in photo below), instead of 180-degree opposition (green arrows).
The result was that, when I put the
derailleur back together and rotated the cage into the proper position, the
back tension was either too little, causing chain to droop, or too much,
twisting the spring in on the center bolt and hindering its ability to turn
smoothly. I also knew from past experience that this would eventually ruin the
spring completely by bending it out of shape!
Luckily, I have found the correct
replacement spring from a dealer of vintage small parts in the U.K. – and I’ve been
trying to be patient waiting for it to arrive!
My friend Lenny had originally planned to
drive down from Boston to visit Philadelphia and was going to drop off his De
Rosa bicycle at my place. With all of the appropriate parts ready to go, it
should have been an easy day’s work swapping out his vintage Campagnolo Super
Record parts with a more modern Centaur group. It was a good thing he ended up
changing plans and decided to ship the bike here, because there were a bunch of
little complications that would have left him with disappointment and a long,
empty-handed drive home.
I immediately realized that we had not
double-checked what type of mount the De Rosa had (clamp style) for the front derailleur, and
of course, the Centaur group had the wrong one (braze-on). I then found that the
drive-side cup of the bottom bracket would not budge, so I was off to Bikesport
for some extra leverage help.
Finally, when attempting to true the wheels,
one of the rear spokes had been over-tensioned by the previous owner and “POP!”
Of course, the Campagnolo bladed spokes had to be specially ordered, as they
are not of an off-the-shelf design. The rear wheel also had an asymmetric
shape, so spoke lengths are different on each side.
I was a bit stunned to hear the Campagnolo
spoke kit cost over $100, until I realized that was a complete set required to
build a wheel. I found a mini kit for much less, with included a pair of spokes
for the front wheel and a couple for each side of a rear wheel. Lenny and I
both thought it would be a good idea to have a few spares on hand, just in case
another spoke would break in the future.
Here is a
quick shot of Lenny’s bicycle before I had to partially disassemble it for
return shipment:
Next time
around, I'll share news of an interesting twist to one of my “on deck” projects.
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