Steve writes: "... I had a 104" top gear on my 1972 P-15 Paramount as originally delivered. I found it way too high. I changed the freewheel (had no choice, really: the shop destroyed the Regina Oro when trying to remove it for the first service) to one with a 15T that brought the top gear down to a 97" and found that it made a huge difference: top gear was now usable. It made as profound a change in the usefulness of the bike as switching the granny to a Merz 31. That was a 27 x 1 1/4" wheel, 54T big ring. Make of that what you will. ..."
Of which I make Steve believes a 27x1-1/4" wheel has an effective radius of 27" That he found the 54-14 104" top gear on his 1972 P-15 Paramount too high for his liking. That the ~7% smaller 97" gear he got by replacing his 14-xx freewheel with a 15-xx one suited him much better. On Monday, January 2, 2017 at 7:29:29 PM UTC-8, Steve Palincsar wrote: > > On 01/02/2017 06:37 PM, ted wrote: > > > John wrote: "46-11 = 113GI, pretty high for all but pros". When I see the > term "pro" there I think of somebody who makes a living racing a bicycle. I > was never a pro, never even really competitive as a middle aged local cat 4 > racer wana be, but I did find a 116" gear (53-12 with 700c 23mm tires) > useful on group rides with a local racing oriented group. So I think John > seriously over stated how high a 46-11 gear is. It wouldn't surprise me if > competitive local cat 3 racers (a long way from pro caliber) found a 50-11 > combination (yielding ~120GI) useful. > > > Use cases for 50x11 (or gears that high in general): > > - tandems > - sprinting at the finish of a race > - very strong riders riding fast in a pace line > - pedaling while going down several mile long hills > > Making your living riding has nothing to do with it. > > > > > Veering onto antique standards, John wrote: "... from 52-14 130BCD days" > I had no idea 130BCD cranks with 52t big rings and 14-xx > freewheels (emphasis on the 130BCD) were ever a common thing. I take it > thats what 70's Schwinns had. > > > 1970s Paramounts had Campagnolo Record cranks. 144mm BCD, I think. > > > Learn something new every day. > I always thought the Campi 144BCD was standard back then and that the > 130BCD standard emerged much later to allow the 39t small ring (as opposed > to the previously prevalent 42) of the 53/39 cranks that were ubiquitous on > "racing" bikes before 50/34 110BCD "compact cranks" came on the scene. By > that time I believe cassettes typically started at 13, 12, or even 11 > teeth. So I didn't think there was ever a time when 52-14 top gears and > 130BCD cranks went together. Not that that is of any importance, just > saying thats what I thought. > > If anybody is still reading, I apologize for the impending snarkyness but > it seems I can't help myself. > > > Work on it. > > John recommends 98-100 inches which is 99" plus or minus 1". He also says > 2" is insignificant, and says 103" is too high. I find all that rather > inconsistent. If 3" too many is too much, I wouldn't think 2" is > insignificant. Does the transition from insignificance to excess occur in a > delta of <1%? If 2" is insignificant, why not 97 to 101"? If the target is > 99" why all the talk about a magic and recommended 100" value that he seems > to treat more like an upper bound than an actual target? > > > All snarkiness aside, I had a 104" top gear on my 1972 P-15 Paramount as > originally delivered. I found it way too high. I changed the freewheel > (had no choice, really: the shop destroyed the Regina Oro when trying to > remove it for the first service) to one with a 15T that brought the top > gear down to a 97" and found that it made a huge difference: top gear was > now usable. It made as profound a change in the usefulness of the bike as > switching the granny to a Merz 31. That was a 27 x 1 1/4" wheel, 54T big > ring. Make of that what you will. And back then, I lived in the > Catskills, where we did have some big long mountains to ride down, unlike > now where most of my "downhills" are stream-cut gorges no more than 150' > deep and 0.3 - 0.6 mi. > > These days, everything of mine is in the 96 - 99" range (except the > Moulton, which is in the mid-80s). > -- 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.
