I wonder if the problem was initially mid-described. Perhaps it's not "slipping" at all, perhaps it's what many of us have long called "ghost shifting."
Zack is friction-shifting Hyperglide 9. Hyperglide is designed to let the chain sit on 2 adjacent sprockets at the same time without clattering. Indexing can be tuned to make the shift perfectly; with friction shifting you are dependent on auditory feedback to align the chain, and it's largely absent. So what does this mean in practice? My experience friction shifting Hyperglide 8 was that I'd downshift approaching a light or stop sign, and thought I was correctly aligned. I'd stop, and when loading up the drive train on start-up, the bike would upshift with a BANG. I switched that bike to index shift levers and all is well. I moved the friction shifters to a bike running Hyperglide 7 and all is well there. 7 is spaced wider, i.e., the sprockets are farther apart from each other, making it easier to align the chain. I also discovered something entirely counter-intuitive and counter to long established "old timey" practice. In the old days, when you downshifted you relieved pedal pressure on the drive train. That made shifting much easier. What I found with Hyperglide is that if you load the drive train, i.e., put pressure on the pedals, the downshift becomes snappier and more positive, engaging the next sprocket with a clunk. On Sun, 2012-07-08 at 20:33 -0700, rob markwardt wrote: > Late to the party. My new bike has a 105 long-cage on back, Silver > friction shifters, and an 11-30 8 speed cassette (46-30 rings up > front). Shifting is perfecto in all gears. > > On Jul 7, 7:45 pm, Zack <zack...@gmail.com> wrote: > > I am currently trying to eliminate a truly annoying chain slip on my > > new-to-me 62 Hunq, and it occurred to me that I am using a new-to-me > > derailer, and that could be causing the problem. > > > > Should it cause me a problem? > > > > I have the sugino triple crank, and the standard riv 8 speed cassette 11-32. > > > > The derailer is a Shimano 105. I checked the range of the derailer when I > > set it up, it flexes out to the biggest ring on the cassette and is lined > > up to the smallest. Derailer hanger is not bent, also checked. Greased > > underneath the bottom bracket where the cables go through the cable guide. > > Silver shifters are beeswaxed and tightened. No apparent sticky link (i > > checked by paying close attention to the chain running through the RD, > > nothing was jumpy/weird). > > > > Slipping occurs under load, probably either in the middle or small > > chainring, happens when I stand up and try and crank (i am about 230 lbs). > > > > Help appreciated. > -- 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.
