Congrats. Nice outside-of-the-box thinking. Reminds me of the violent front brake shudder I cured by toeing the brakes OUT as far as I could.
Gernot On Sep 7, 5:33 pm, NME <nicolemea...@gmail.com> wrote: > Thank you all for your really insightful comments! I tried a few more > things, including some your suggestions -- made sure the wheels were > aligned, checked tire pressure, etc. > > I noticed that the problem was much worse when I was on smooth > asphalt, but would almost disappear when I was riding on gravel, > cobblestones, or bricked sidewalk, so it occurred to me that the > problem was this "harmonic" vibration -- not that the bike was out of > alignment, but that it was too perfectly aligned. So on a whim, I > *loosened* the bolts to the rack -- not enough that the rack wobbles > or is in danger of coming unscrewed, but just enough that there can be > some miniscule "give" between the rack and the frame. My idea was > that if I could disrupt the perfect transmission of this vibration, > then it wouldn't radiate to the front wheel, but would cancel itself > out. > > It was the exact opposite of DougP's suggestion and the opposite of my > original inclination, but it worked! It went from violent shimmy to > completely smooth. No shaking at any speed. > > Is this perhaps another version of the "self-restoring force" Ken was > talking about? (The maths are also beyond me.) In any case, if the > problem happens again in another context, I'll be sure to look into > "tire damping" (nice term) as a first resort! > > -- > > Thanks again, everyone! I'll finally be posting pictures of my AHH > soon, now that I've got it properly scratched up and broken in. Five > months in Berlin, and besides the daily commute, a few wonderful day > rides already, and and now some inn-to-inn rides planned for fall. > > Nicole > > P.S. in answer to Ken's question -- neither me nor my mechanic are > well-skilled. -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bunch@googlegroups.com. To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.
