Needle bearing headsets have quite a lot of drag, even when adjusted perfectly. For that reason alone, needle bearing headsets are a pretty common remedy for shimmy. I don't have first hand experience curing shimmy with one.
This type of front end shimmy is usually considered a harmonic oscillator, which is modeled in math as a spring/mass/damper. The wikipedia page on Damping has the math. Moderate to severe shimmy on a bicycle will continue indefinitely until you grab the bars or squeeze the top tube with your knees, which is typical of an underdamped system. The ways to get out of that are to change the frequency of your oscillation (difficult and/or confusing guesswork) or add damping. Your hands on the bars adds damping. A steering damper adds damping. A headset with some drag adds damping. There are many anecdotal reports out there that "my bike shimmied like crazy on my ride to the shop, where we installed a needlebearing headset. The ride home on the identical bike I could not make it shimmy". The model that Riv sells is only half-needle bearing. Maybe that's enough damping. It's an empirical question. On Tuesday, April 30, 2013 8:50:27 AM UTC-7, Jim Thill - Hiawatha Cyclery wrote: > > IMO, the needle beating headsets were an improvement when they came on the > scene (in the age of crummy headsets), but in this day and age, I don't > know why anybody would bother. > > I believe Cane Creek, King, FSA, VO, and perhaps others, all make/sell > cartridge bearing headsets. The Shimano 105/Ultegra/DA headsets > discontinued a few years ago are excellent and still floating around. > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en-US. For more options, visit https://groups.google.com/groups/opt_out.
