Campagnolo Nuovo Record Derailleur Pulleys
February 26, 2012
Is this guide helpful?
This guide concerns the older style(1970's-1980's) Campagnolo derailleur pulleys or jockey wheels as they are sometimes called. On many of these you will notice a straight "line" from the center of the gray plastic to the outer edge, usually at the peak of the tooth. Some sellers believe these lines to be molding lines or seams from production. They are in fact, cracks. You can determine this by placing the edge of a razor blade or exacto knife into the "line". I have one pair in which the "line" has opened up enough to see daylight through. I would not use these pulleys at all. They are only good for display. I believe that the cracks are from age and temperature extremes. I have seen them on SunTour and Sachs pulleys from the same era. I can find no documentation that these are production seams. If this is true, why do they appear randomly? Even multiple molds are made from a single casting so the "lines" would appear at the same location on every wheel. The production techniques from this era do not support the theory that these are molding seams. This being said I cannot understand why any seller with a cycling background would pass these off as molding seams. Any cyclist with a basic understanding of a bicycle should understand that cracks are bad. I believe that the type of plastic used during this period has much to do with this phenomena as it was pure plastic resin without the additives available now to increase overall strength. There could have been manufacturing inconsistencies also that may have affected production as well. The fact that these lines appear almost always on the gray colored pulleys supports these beliefs. The cracks are very visible with a simple magnifying glass. You can clearly see a split and not a raised seam as a mold would leave. My other piece of evidence is the fact that I have one pulley that, until recently had no crack and now has a very fine "line" which is clearly a crack. Why the cracks are straight across the surface and not jagged or curved or why the crack intersects at the peak of the pulley tooth is still not known but I hope to find out. I'm sorry if this upsets some people but the buyer and seller have a right to know. Jeff