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#1
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Need 39t ring for old campy crank
I really need to gear down my old road bike to
suit my advanced years and weakened quads. Currently riding an old 70's Campy NR crank with 53-43 rings. Would love to change the 42 to a 39. Will a 39 t ring fit the crank?? What inner rings might fit an old NR, Sugino??? tnx chuck |
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#2
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Need 39t ring for old campy crank
cciaffone wrote:
I really need to gear down my old road bike to suit my advanced years and weakened quads. Currently riding an old 70's Campy NR crank with 53-43 rings. Would love to change the 42 to a 39. Will a 39 t ring fit the crank?? What inner rings might fit an old NR, Sugino??? tnx chuck Chuck, As an old Campy rider myself, I can say that 42 was "officially" the smallest ring you could get. However, I know that at least one maker produced a 41 that would also fit. Getting a 39 is out of the question due to the crank spider's 144mm bolt circle (see http://www.sheldonbrown.com/gloss_bo-z.html#bcd). To achieve your ends, I have had to move to newer cranks. This isn't necessarily a bad thing since those old cranks can and definitely do break (see http://pardo.net/bike/pic/fail-009/000.html). I have the pedal eye snap off the arm at an inopportune time (isn't that always the case) causing a crash on a short but sharp uphill I was charging at. If you want to keep that retro look and some of the other characteristics of those old cranks, see the Velo Orange website at http://store.velo-orange.com/index.php/components/cranksets/cranks.html. While it is a track crank, this new Phil Wood crank (see http://velonews.competitor.com/2011/08/bikes-and-tech/eurobike-day-one-the-big-brands-can-wait_190644/attachment/phils-crank) does use the same BCD as your current crank. But I doubt they will make a road double model. |
#3
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Need 39t ring for old campy crank
In article ,
cciaffone wrote: I really need to gear down my old road bike to suit my advanced years and weakened quads. Currently riding an old 70's Campy NR crank with 53-43 rings. Would love to change the 42 to a 39. Will a 39 t ring fit the crank?? What inner rings might fit an old NR, Sugino??? tnx Will not fit. Easiest is to replace with a triple and keep the corncob. Probably will need to replace the front changer, but maybe not. -- Michael Press |
#4
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Need 39t ring for old campy crank
Well thanks for all the help. Not what I really
wanted to hear, but ... the alternative is to get fit again, I guess. Kinda scary to get old. chuck |
#5
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Need 39t ring for old campy crank
Michael Press wrote:
In article , cciaffone wrote: I really need to gear down my old road bike to suit my advanced years and weakened quads. Currently riding an old 70's Campy NR crank with 53-43 rings. Would love to change the 42 to a 39. Will a 39 t ring fit the crank?? What inner rings might fit an old NR, Sugino??? tnx Will not fit. Easiest is to replace with a triple and keep the corncob. Probably will need to replace the front changer, but maybe not. I would strongly urge you to NOT go with a triple. It is by far not the easiest or most cost effective way to get lower gearing or a wider range. Going from double to triple, assuming you have a full old-style Campy setup, will likely require (a) new crank, (b) new BB, (c) new FD, (d) new RD, (e) new chain. Better to consider compact gearing which employs smaller chain rings on a new crank - typically with 110mm BCD (since your existing crank will not support this). In this case, the most you will have to do after swapping cranks is lower your FD (if clamp on, this is easy but can usually be accomplished with a braze-on - if not, I have a "fix") and cut a couple links from your existing chain. With compact gearing, you can get very close to the same gear ratio ranges as one would expect from a road triple plus you retain the snappier shifting and lower weight that is often lost with triple cranks and FD. Spend a few minutes with any gear chart or calculator and you can see for yourself. If you still need shorter gears, you might be able to add a slightly larger cogset on the back. depending on the cogs involved and your RD make/model, you may have to consider a new RD. But many old Campy RD can support up to 26 or 28 teeth back there. |
#6
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Need 39t ring for old campy crank
On Sep 1, 11:13*am, David White wrote:
Michael Press wrote: In article , *cciaffone wrote: I really need to gear down my old road bike to suit my advanced years and weakened quads. Currently riding an old 70's Campy NR crank with 53-43 rings. Would love to change the 42 to a 39. Will a 39 t ring fit the crank?? What inner rings might fit an old NR, Sugino??? tnx Will not fit. Easiest is to replace with a triple and keep the corncob. Probably will need to replace the front changer, but maybe not. Lot of false statements in this post. I would strongly urge you to NOT go with a triple. It is by far not the easiest or most cost effective way to get lower gearing or a wider range. A triple is the easist. New crank and bottom bracket and you have very low gears and a wide range. Compact cranks do not get you much lower gears. Assuming the normal change from a 39 ring to a 34 gets you about 13% lower gears. Not much really. With a triple you can go from a 39 or 42 to a 30 inner chainring. But of course anyone with a brain replaces the 30 tooth inner ring with a 24 tooth ring to get rreal low gears. From a 39 or 42 to a 24 and you get very low gears. Going from double to triple, assuming you have a full old-style Campy setup, will likely require (a) new crank, (b) new BB, (c) new FD, (d) new RD, (e) new chain. Yes new crank and bottom bracket. Although I would likely try the new square taper triple crank on the old bottom bracket and see if it clears the chainstays. If so then no need for a new bottom bracket. No new front derailleur required. Double front derailleurs shift triples just fine. I had a Sora double shifting a 45-42-20 triple crankset. No new rear derailleur required. A short cage rear derailleur will wrap enough chain to use all but the small ring and small cogs. You don't use those cogs anyway so no need to worry about them. And having the chain hang loose on the bottom does not cause any harm anyway. New chain? Your old crank is 53 big ring. Triple is 53 big ring. Same cassette. Why would you need a new chain? Do you own stock in a bicycle chain manufacturing company and want everyone to replace their chain every week? Better to consider compact gearing which employs smaller chain rings on a new crank - typically with 110mm BCD (since your existing crank will not support this). In this case, the most you will have to do after swapping cranks is lower your FD (if clamp on, this is easy but can usually be accomplished with a braze-on - if not, I have a "fix") and cut a couple links from your existing chain. With compact gearing, you can get very close to the same gear ratio ranges as one would expect from a road triple plus you retain the snappier shifting and lower weight that is often lost with triple cranks and FD. No. Compact cranks don't provide anywhere near as low a gear as a triple. Triple cranks can accept a 24 tooth inner chainring, 74mm bcd. Compact cranks with 110mm bcd can accept a 33 ring. Big difference between 24 and 33. Snappier chifting? My triple bike shifts between the 52 and 42 rings as nicely as my double bikes shift between chainrings. Of course I use Campagnolo shifters on that bike. But even my touring bike with 44-33-20 rings shifts between the outer and middle rings just fine. It uses 5700 shifters. Spend a few minutes with any gear chart or calculator and you can see for yourself. If you still need shorter gears, you might be able to add a slightly larger cogset on the back. depending on the cogs involved and your RD make/model, you may have to consider a new RD. But many old Campy RD can support up to 26 or 28 teeth back there.- Hide quoted text - - Show quoted text - |
#7
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Need 39t ring for old campy crank
cciaffone wrote:
I really need to gear down my old road bike to suit my advanced years and weakened quads. Currently riding an old 70's Campy NR crank with 53-43 rings. Would love to change the 42 to a 39. Will a 39 t ring fit the crank?? What inner rings might fit an old NR, Sugino??? Revised series Nuovo Record (post-1968) are 144mm making 42t the designed minimum. There were 41t made but some runs of that crank may need a touch with a file on the crank web between rings if the chain links hit. (42 to 41 is a tad past two percent change, i.e., not much) [1060~1968 original Record were 151mm, hence 44t low] Modern (post-1986) Campagnolo road sets are 135mm with a 39 low. Square taper format start about $95, UT format about $190 Modern compacts are mostly 110mm with a 34t low (34-48, 34-50 etc) Start about $50, Campagnolo from $149. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
#8
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Need 39t ring for old campy crank
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#9
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Need 39t ring for old campy crank
On Sep 1, 3:45*pm, cciaffone wrote:
I really need to gear down my old road bike to suit my advanced years and weakened quads. Currently riding an old 70's Campy NR crank with 53-43 rings. Would love to change the 42 to a 39. Will a 39 t ring fit the crank?? No, 42 teeth is basically it. Now many of the rear derailleurs were advertised as capable of using a 28 tooth rear sprocket with a 1" derailleur hanger and and 10 tooth difference in the front. You will find however that more can be squeezed out of them particularly if you have a smaller difference in ring size. The racing freewheels of Regina went to 31 (or32) and Maillard to 32. If you want lower gearing than these can accomplish then a longer gear hanger is usually appropriate for reaching to a 36 or 40 (if you can source it) rear sprocket. Stretching the rear derailleur capacity with a big sprocket will result in real gear changes unlike changing from 42 to 39 ring. What inner rings might fit an old NR, A 144mm BCD Nouvo Record can be fitted with a fabled 41 tooth up to whatever clears your chainstay. Sugino??? I'd take a guess that's the same BCD of 144mm and also limited to the generally available 42 teeth and bigger. tnx chuck |
#10
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Need 39t ring for old campy crank
On Sep 1, 9:45*am, cciaffone wrote:
I really need to gear down my old road bike to suit my advanced years and weakened quads. Currently riding an old 70's Campy NR crank with 53-43 rings. Would love to change the 42 to a 39. Will a 39 t ring fit the crank?? What inner rings might fit an old NR, Sugino??? What is your layout on the freewheel on this bike? Assuming you're at maximum there too, what about more modern components, if you're going to make a change anyhow? (possibly superfluous discussion follows): FWIW, I have a "contemporary" (more or less) Campy triple setup on a nice old steel Tommasini with horizontal dropouts. It works great; you can't "powershift" onto the inner ring but otherwise the shifting is very much on a par with the Campy double setups I have on the other two bikes in "the fleet". I'm talking Record/Centaur brifters (handlebar shifters) and a mix of Record/Chorus/Centaur/Veloce components on the various bikes. A triple works for me partly because I had a Campy triple back in the late 70's-early 80's, which I used for touring (camping but not "survival level") in the Rockies. You keep your normal "road gears" and get a low (even with a 36t inner ring as on the N. Record triple crankset). With the 30t inner ring on the Veloce triple, the low is low enough to keep a road-ratio cassette (which is not a "corncob"), something like a 13-23 as I have, so you have closely spaced gears and a low range added. Hey, I never "got over" the 42 inner (or middle) chainring. Climbing on the 42 and off the 39 was like coming home g. Evidently, I'm not much of a Compact candidate, although again FWIW, some older riders I know of "went compact" and love it, while others came back in something of a hurry. No telling who will like what, there. I just wanted to testify in behalf of the modern triple, as a user. Brifters? No culture shock there. Better shifting (by far), better braking, which is much easier on the old fingers, like power-assist auto brakes compared to the old Nuovo Record stuff and again, the newer gear works just fine on fine old bicycle frames with horizontal dropouts. Um, "getting back in shape" might be an option but let's just say I too broke a Nuovo Record crank at the usual/required "bad moment" (with a safe landing, fortunately) and my "old stuff" or at least the old old stuff, has been retired. --D-y |
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