RE: [CR]re: headset index

(Example: Framebuilding)

Date: Tue, 27 Mar 2007 09:40:41 -0700 (PDT)
From: Donald Gillies <gillies@cs.ubc.ca>
To: classicrendezvous@bikelist.org
Subject: RE: [CR]re: headset index

Have you tried all the typical techniques to minimize indexing ??

- Probably the best first step is to purchase a Tange Levin lower race, about $4+S/H at http://www.biketoolsetc.com. This has a slightly smaller outside diameter so I'd use lots of grease and/or wax paper in the lower cup and then pack some silicone in and allow it to dry, forming a tighter seal. Maybe do this off-the-bike. Be careful not to get silicone on the campy cups as it has acetic acid and may etch the cup.

- increase the number of ball bearings: remove the retainer, put in too many bearings and then take out ONE.

- turn lower cups and cones by 90 degrees. Or turn all 4 cups/cones. Experiment to see what produces the least indexing.

Perhaps the last technique is this :

- make sure you adjust the preload using the locknut of the headset so that the top cup/cone is taking some of the weight. Part of the reason why the bottom wears out soonest is that a loose top puts the entire weight of the bicycle on the lower cup and cone, and what's worse, looseness allows flexion in the head tube. (in a nonscientific survey of 20 bikes, the indexed bikes tended to have longer reynolds 531 head tubes than the non-indexed bikes ...)

- Don Gillies
San Diego, CA