Thursday, May 31, 2012

#2B or not...

What a treat to work on Cunningham #1B recently and then #2B comes in for some work.  Initially, #2B was going to come in for new, while-you-wait, decal application.  The decals are a two layer application.  First layer is the decal with a second layer that is clear and protects the first layer.  They were reproduced in the exact style as the originals with great attention to detail including the rounding of the corners.  

One of the first things I do when a bike is brought in to me is to give the brake levers a squeeze.  The bike equivalent of kicking the tires in a car lot.  In this case, the brakes felt like ... well, they felt bad so the bike stayed for some attention.  In addition to some brake work, the bars got re-taped in the fashion of the early Marin drop bar bikes.  

With roller-cam brakes, one of the main culprits in poor brake "feel" is fouling of the sealed bearings in the rollers.  This was the case on this bike.  Both brakes were pulled, disassembled completely, and the seals popped off the rollers so they could be soaked to break up and clean the bearings.  A little soak, a little flush, a little compressed air drying and the rollers spun completely free.  The seals were reinstalled after a little grease was smeared into the bearing and the brakes were once again working like a Swiss watch.  New cables and housing helped too.  

The style of taping the bars back in the day was to cut a drop bar Grab-On grip in half, trim to length, lay it on the top half of the bar, and then tape over it all with cloth tape.  Cloth tape on a mountain bike is much more durable than the cork or gel tapes commonly available.  The cork tapes and similar are prone to cutting and tearing.  Cloth just gets scuffed a bit and even if it gets torn, it's not going to unravel.  On my personal bikes, I only use this half a Grab-On on the drop portion of the bars.  That's the only place my hands were when it's rough and I am in a technical situation.  When I'm riding on the tops, I'm either climbing something non-technical or in cruise mode.  I did the full top and bottom Grab-On tape job on this bike.  Some folks like it.  

I also found out that #3B has been through the shop having been purchased locally by a friend back east and dropped off here for shipment back east.  Cunningham trifecta.

#2B

#2B

#2B

#2B

#2B
Not a new decal.  I left this one untouched.


#2B
Tape and straight line to aid in decal application.

 #2B

#2B

#2B
One half of the bars done.  The other half started showing the Grab-On base position.  The brake lever bodies were removed prior to taping and reinstalled over the tape.  Very clean.

#2B

#2B

(What's playing:  The Louvin Brothers Give This Message to Your Heart)

3 comments:

classen said...

As I formulate ideas for my homage to a Dirt Drop Cunningham, I am really enjoying all your photos and insights. One thing that I'm unclear on is how the gooseneck stem is attached to the steerer. I've seen photos on one of your previous entries of the type II fork with the cone-shaped nub, which I assume is important for securing the gooseneck stem, but I'm unlearn on how it works.

cheers

gypsybytrade said...

Mike, I'm loving these Cunninghams. The details on these bikes are amazing. Above beauty, they are hyper functional. I have wrapped cotton over old cork tape for a similar effect. For now, I modify and install Ergon grips to the drops for longer days. It's supreme, but the Grab-On foam is much simpler.

I remember an ergonomic rubber grip for drop bars by Morgan Concpets that came on a used Viscount. I really enjoyed that, compared to the narrow diameter of drop bars with a thin layer of tape.

Great stuff.

blackmountaincycles said...

The LD type stems typically attach to the fork via a brazed in 7/8" stub on top of the fork or clamp to a quill stub that is secured to the fork much like a quill type stem.