[CR]Learco Guerra test ride part 2


Example: Events

From: "Aldo Ross" <swampmtn@siscom.net>
To: <classicrendezvous@bikelist.org>
Date: Wed, 9 Jul 2003 10:22:58 -0400
Subject: [CR]Learco Guerra test ride part 2

(First, a few corrections - Jan's Guerra has Ambrosio stem and bars, not Cinelli steel. Also, Wilier Triestina bikes did not use "dragonfly" Labellula tubing. . . I was confusing two different bikes - a Guerra and a Wilier - that a friend owns. And although I thought the parts were all original, this proved not to be the case for the bb and crankset. More on that below. AR)

A Ride Into The Pits part 2 - "Assemblation of the Chain-Bending Mechanistics"

Everything went together easily. It helps when there are guides built-into the bike. "See that area of clean paint, surrounded by a 50-years accumulation of crud and grime? Find a part that matches the shape of the clean area, and bolt it in place."

Bizarrely, when everything was installed and adjusted, the chain (still on the bike when it arrived) was 2 links too long for the PR mech to work properly. I wonder how the original owner got away with that? Perhaps he'd switched to "digital" shifting at some point?

With everything bolted on and checked twice, wrenches in my pocket, tires pumped, and helmet strapped securely on my noggin, I took my first test ride around the neighborhood. First thing I noticed was the toeclips dragging the ground. "Huh - must be a really low bottom bracket." Second thing I noticed was how very rigid the steel bars and stem felt. The bike seemed straight and true, and rolled comfortably on big soft clinchers. The saddle has 50 years of break-in, and is as soft as a glove.

After a few minutes it was time to try a shift. Bike has a 5-speed 14-22 fw. Shifting from the 20 to the 18 was easy - stop pedaling, open lever 1/4 turn until shifting fork pops up into place with a "click", pedal backwards and move lever to shift onto the 18, stop pedaling and close the lever. Before it disengages, the shifting fork pushes against the chain, and there's a little metal finger and cog which rolls the axle forward slightly while the qr is closing - these two things together provide the necessary chain slack to prevent binding.

Another shift, into the 16. Then another, into the 14. Piece of cake. Then I tried to shift back into the 16 - the fork pushed against the chain, but not enough to shift it before the qr cam engaged again. I tried several more times, but all it did was push gently on the chain, bending it nearly to a shift, but not quite enough. My heart sank as I began to suspect this thing was too worn-out to work properly.

I stopped and shifted by hand, then returned home to look things over. I have a spare PR unit, which I compared against the one on the bike. No difference except the spring which snaps the shifting fork into place feels stronger on the spare. OK - I'll switch them and everything will be all right. But as I started removing the mech I felt a knurled nut spin slightly. This nut seems fixed to the lever rod on the spare unit, but was pretty loose on the mounted one. It sits directly below the shifter fork spring tube thingie, and as I turned it I realized it's the adjustment for the spring tension! The one on the spare was so full of dirt and junk it only FELT fixed. (Some Kroil loosened that one too.). So back on the road we went. . . shift down, shift up, shift down, shift up, shift down, shift up. Now it was working perfectly!

:::whew:::

next time part 3 - An Embarrassing Discovery

Aldo Ross
Middletown, Ohio