Hugh There's a conflict in your measurement procedure, or I'm confused, or both.
You say your chainrings all are 4-bolt. That is to say, each chainring is held to the spider with four chainring bolts. Is this right? If so, you measure the BCD by measuring OPPOSITE bolts, not adjacent bolts. If it's 94mm BCD, it will measure 94mm. You say you used the linked chart, but that linked chart is exclusively for 5-bolt rings. 5-bolt rings have no opposite bolt to measure, so you measure the adjacent one and look it up on the chart. So, if you really have 5-bolt rings, then you did the right measurement and you came up with the right BCDs. Rings in the $20 range are findable for that BCD, and are all decent. But, if you really have 4-bolt rings and really measured the adjacent bolts at 34mm and 55mm respectively, then you don't have 58 and 94mm BCDs respectively. Bill Lindsay El Cerrito, CA On Monday, January 18, 2016 at 9:53:00 AM UTC-8, hsmitham wrote: > > Hello Rivendellians, > > I have a 1995 Salsa Ala Carte and I'd like to rehab it with a new drive > and cockpit. It has the original Salsa chromoly stem 130mm and have > considered throwing on a Ritchey 30ยบ rise 80mm stem & straight MTB bar for > more comfort. The current setup I'm pretty stretched out.The old rapid fire > shifters just don't work, I've tried lot's of things to get the shifter > working (advice from LBS) but it seems easier to just buy new one's. > > The drive is 8 speed and has a Cook Bros Crank *(they went out of business > in the early 2000's) which has a 4 bolt spider. I measured the inner bolts > distance between adjacent bolts and determined it was a 58mm BCD ring, I > also measured the outside bolts between adjacent bolts and figure it's a > 94mm BCD ring. I used this chart which seemed the only one that had my > measurements, 34mm & 55mm respectively. It seems MTB's with all the new > tech have left these BCD's behind. > > http://www.bikeforums.net/classic-vintage/704206-chainring-bcd-chart.html > > I went to the Peter White page and found this page > http://www.peterwhitecycles.com/chainrings.asp > > The TA Carmina rings seem like the right ones? But man are they expensive! > > Is the bike worth keeping it somewhat period/vintage? Have I measured > this correctly? Are there other ring manufacturers making these ring sizes > and importantly less expensive. I've seen Vuelta and Real rings but just > don't know whether their quality rings? > > I could just purchase a SLX 10 speed group for $230 and be done with it. > > *I heard Cook Bros came back in 2010 but with limited offerings but my > search has been fruitless in terms of info regarding BCD ring sizes. > > So thanks in advance for any wisdom the group can dispense. > > ~Hugh > Los Angeles, CA > > > > > -- 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 https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
