[CR]installing Margherita - Pt.1

(Example: Framebuilding:Restoration)

From: "swampmtn" <swampmtn@siscom.net>
To: <classicrendezvous@bikelist.org>
Date: Thu, 7 Dec 2000 23:35:53 -0500
Subject: [CR]installing Margherita - Pt.1

This is part one of my attempt to describe the installation of the Vittoria "Margherita" shifter on one of my bikes.

Heaven help me.

Tools you will need:

1) screwdriver with medium, sharp tip 2) screwdriver with narrow, sharp tip 3) Campy T-wrench with 8mm socket end 4) Two 8" adjustable spanners 5) chain tool 6) freewheel tool 7) 12Lb sledgehammer 8) bottle of Glayva Scottish liqueur

On careful examination it became obvious that the three clamps for mounting the tension arm pivot and actuator guides were too small for most recent Columbus or Reynolds chainstays. This eliminated 21 of my bikes as possible recipients of the Margherita, but luckily I did find one bike that would work - Legnano Gran Premio (from about 1960). The chainstay was the correct diameter, the cottered crank held the right crank arm several mm from the bb cup, and the chainstays were long enough to fit the connecting linkage.

I began by removing the derailleurs, shift levers, chainrings, and all cable guides. I was pleased to find that all nuts and bolts came loose without any need for the 12Lb sledgehammer.

I disassembled the pulley to check the condition of the grease, and Boy! was I surprised to find that there wasn't a spec of grease or oil inside. Of course, that meant there was nothing holding the balls in place, and they promptly dissipated around the office floor. It took 20 minutes of trawling with my mega-magnetic bar to collect all the escapees.

Assembly started at the front. I connected the linkage rod to the coil spring linkage, then place the tension arm pivot clamp on the right chainstay, as far back against the chainstay bridge as possible (to give the tension arm maximum range of movement). I hand-tightened the clamp nut and bolt, and layed the linkage rod in position on top of the chainstay. I loosly fitted the mounting clamps for the rod, and installed the shifting assembly in roughly the correct position.

It took awhile to get all the clamps in the right positions... too close, and the shift assembly sticks. Properly spaced, everything moved quite freely. Next I placed the toothed rack over the top of the tension arm, and clamped it loosly in place. After I reinstalled the single 50t chainring, I was able to tighten the rack in about the right spot.

I decided to use the 15-17-19 3-speed freewheel, so I removed the 5-speed. Next I laid the chain over the middle cog, over the chainring, and through the chain holder around the pulley. I moved the tension lever to the middle of the rack, and checked the chain length. I had to remove 3 links of chain. After that, I started tightening all the bolts, adjusting the position of parts as I went along.

Without any instructions, I had to rely on the picture from the box top, and some engineer's intuition to get things in the right orientation. It quickly became apparent that the pulley was not in the right spot - pointing out and the bottom rear. The chain just skimmed across it's surface until jamming against the chain retainer. Now the scarey part - take the two adjustable wrenches, tighten them onto the flat section of tension arm between the pivot and the pulley, and twist the arm to align the pulley with the chain.

Done successfully, you may now drink one shot of Glayva.

It took awhile to readjust everything to work together, but finally I was able to do a few successful shifts in the work stand.

Tomorrow - Pt.2, The Road Test