PX-10 gearing
01-04-22 | 07:17 PM
#26
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The stock crankset on the Raleigh Lenton Grand Prix of the late 1950s/early 60s had 49/46t ring combo. I think it was to discourage shifting the FD!
01-04-22 | 07:23 PM
#27
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From: Sacramento, CA
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I have it on a few bikes.
01-04-22 | 07:28 PM
#28
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From: Sacramento, CA
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01-04-22 | 07:59 PM
#29
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From: Ann Arbor, MI
Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8
It’s very hilly where I live in the Western Catskills, with many of the secondary and seasonal roads I ride on having quite steep grades. When I got back into cycling last spring I had to rework the gearing on my Cannondale so I could handle the hills (while a touring model, a PO had put a road-triple 30/42/52 and not-very-wide cassette on it- I replaced with 26/38/48 chainrings and an 11-34 7sp cassette). 2k of riding this past season has helped immensely and I find I’m almost never using the granny now, though I’ll want it if I carry panniers, etc, and no doubt I’ll lose a lot of strength over the winter (no trainer, no space for one….). I do pretty regularly end up on 38x34 on longer, steeper climbs, though. So, I’m trying to decide on a gearing arrangement (friction, btw) for my PX-10 build/rebuild now… I’m not really concerned about higher gearing and spinning out on descents- I’m quite happy to coast, because there’s always a steep climb up ahead. It’s the lower end I want to be OK on.
I need ‘new’ wheels for the bike (it came with crappy, steel 27”)- I’m not having luck finding some more-or-less period-correct 700c wheels locally/cheaply, and if I’m going with new wheels I may as well cold-set the frame to 126mm and go with either a 6 or 7 speed freewheel. I’ve got an SLJ long-cage RD (5500, I think). Also have an SLJ FD to replace the original delrin FD which is cracked.
So my choices seem to be-
1) triple-ize the crank and add a 28t granny and run with a 28t large-cog freewheel. I’ve already got a longer spindle for the BB. 6 and 7sp 28t freewheels seem reasonably common… Research indicates the SLJ FD will handle the triple and the SLJ GT RD has the total capacity).
2) Keep the crank as a double and get the smallest chainring I can (37t) and find a freewheel with a 32 or 34t large cog. 34t gives me about the same lowest ratio I’m able to get away with on my Cannondale, and I think I’d do OK with 32t- though it seems like finding a 6 or 7sp freewheel with a 32 or 34t large cog might be a bit harder than 26t large…
3) Cold-set to 130mm, and get a wheel set that takes cassettes… Still leaves me with the double vs triple question and, really, I’m disinclined to cold-set from 120mm to 130mm….. but possibly more availability with cassette gearing?
$-wise, triplizing will cost me a little bit more (triplizer middle chainring + granny ring) than just getting a 37t ring for a double, though maybe that would get offset by being able to use a more common freewheel.
Yeah, sure, there’s the option of gearing the bike as original, but… no. I live on a dead-end road with something like a half-mile of 12% grade…. and then there’s my long, uphill, dirt driveway after that! Original gearing means an unusable bike for me!
Recommendations? Things I’m missing?
I need ‘new’ wheels for the bike (it came with crappy, steel 27”)- I’m not having luck finding some more-or-less period-correct 700c wheels locally/cheaply, and if I’m going with new wheels I may as well cold-set the frame to 126mm and go with either a 6 or 7 speed freewheel. I’ve got an SLJ long-cage RD (5500, I think). Also have an SLJ FD to replace the original delrin FD which is cracked.
So my choices seem to be-
1) triple-ize the crank and add a 28t granny and run with a 28t large-cog freewheel. I’ve already got a longer spindle for the BB. 6 and 7sp 28t freewheels seem reasonably common… Research indicates the SLJ FD will handle the triple and the SLJ GT RD has the total capacity).
2) Keep the crank as a double and get the smallest chainring I can (37t) and find a freewheel with a 32 or 34t large cog. 34t gives me about the same lowest ratio I’m able to get away with on my Cannondale, and I think I’d do OK with 32t- though it seems like finding a 6 or 7sp freewheel with a 32 or 34t large cog might be a bit harder than 26t large…
3) Cold-set to 130mm, and get a wheel set that takes cassettes… Still leaves me with the double vs triple question and, really, I’m disinclined to cold-set from 120mm to 130mm….. but possibly more availability with cassette gearing?
$-wise, triplizing will cost me a little bit more (triplizer middle chainring + granny ring) than just getting a 37t ring for a double, though maybe that would get offset by being able to use a more common freewheel.
Yeah, sure, there’s the option of gearing the bike as original, but… no. I live on a dead-end road with something like a half-mile of 12% grade…. and then there’s my long, uphill, dirt driveway after that! Original gearing means an unusable bike for me!
Recommendations? Things I’m missing?
If you have the original crank, you can add a granny most likely, getting a longer Stronglight spindle and get a deeper climbing reserve to negotiate that long 12%. This is not exactly complicated, but finding the right parts may take some effort and learning. But ultimately I think this would be best. I'd look into this possibility first. BITD Stronglight had a very deep catalog, so they nearly certainly had the ability to provide parts to make this modification to your white flyer. Problem today is to identify them and obtain them. But that is what I would go for.
01-04-22 | 10:46 PM
#31
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From: Portland, OR
Bikes: (2) ti TiCycles, 2007 w/ triple and 2011 fixed, 1979 Peter Mooney, ~1983 Trek 420 now fixed and ~1973 Raleigh Carlton Competition gravel grinder
I run a triple and 7speed on a Raleigh Competition. A low of 24-28 with stock 28 tooth FWs. Not as nice as my 9-speed good bike with the same low but I won't push a 120OLD past 126. Works very well. (And period correct? Folk have been triplizing PX-10s with TA and Stronglight cranksets forever.)
01-05-22 | 07:09 AM
#32
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Bikes: '38 Schwinn New World, '72 Peugeot PX-10, 78 Raleigh Comp GS, ’80 Peugeot TH-8 tandem
01-05-22 | 08:07 AM
#33
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From: Toledo Ohio
Bikes: 1964 Huffy Sportsman, 1972 Fuji Newest, 1973 Schwinn Super Sport (3), 1982 Trek 412, 1983 Trek 700, 1989 Miyata 1000LT, 1991 Bianchi Boardwalk, plus others
Yes, the big half steps are pretty. My 64 Frejus came with a beautiful 47/50 which was too tall for this old man. Sure is cool looking though. I switched it out for a Superbe which looks like a campy and with 42/47 front and 14-32 five speed in back. Still too tall for you.
That Superbe came off of a Trek and was replaced with a 99 copy SR Apex. I settled on a 34/47 front and a 5 speed 14-32 rear even though a 6 fits the rear. I didn’t like the gear progressions with a 6 and the setup now gives a real nice 1.5 step progression although double shifts are the norm. I could run a triple on this crank, but for the generally flatter terrain here I am happy for now. I like the compact double idea, but playing with the gear calc charts seems to end in frustration with even spaces and 6 speeds in back. Good luck on yours.
That Superbe came off of a Trek and was replaced with a 99 copy SR Apex. I settled on a 34/47 front and a 5 speed 14-32 rear even though a 6 fits the rear. I didn’t like the gear progressions with a 6 and the setup now gives a real nice 1.5 step progression although double shifts are the norm. I could run a triple on this crank, but for the generally flatter terrain here I am happy for now. I like the compact double idea, but playing with the gear calc charts seems to end in frustration with even spaces and 6 speeds in back. Good luck on yours.
01-05-22 | 08:40 AM
#34
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Bikes: '38 Schwinn New World, '72 Peugeot PX-10, 78 Raleigh Comp GS, ’80 Peugeot TH-8 tandem
I think I've decided to go with 45/37 double up front and a freewheel with a 32 or 34 large cog. The 52t chainring I have is bent and I'm not sure I'd be able to straighten it out, so going with a triple in the front would mean all new chainrings, and with the SLJ GT I've got I should be OK with the larger cogs in the back. From a purely aesthetic point, a triple with a smaller freewheel would be a bit more 'stealth', and since I have a longer spindle maybe I'll end up there at some point (and my 50+ year old knees may demand it....), but for now doing/buying less is 'more'!
01-05-22 | 09:27 AM
#35
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From: Washington County, Vermont, USA
Bikes: 1973-4 Gitane Tour de France, early 1970's Lejeune, 1970 Italvega Super Speciale, 2010 Surly Long Haul Trucker 26
I think I've decided to go with 45/37 double up front and a freewheel with a 32 or 34 large cog. The 52t chainring I have is bent and I'm not sure I'd be able to straighten it out, so going with a triple in the front would mean all new chainrings, and with the SLJ GT I've got I should be OK with the larger cogs in the back. From a purely aesthetic point, a triple with a smaller freewheel would be a bit more 'stealth', and since I have a longer spindle maybe I'll end up there at some point (and my 50+ year old knees may demand it....), but for now doing/buying less is 'more'!
I may have mentioned this before, but the best gear calculator I have found is this one:
Bicycle Gear Calculator
Very easy to use and gives a nice visual representation of all the possible combinations.
The 14-17-21-26-32 would combine well with your planned 45-37, and equally well--maybe a little better--with a 46-37. Stronglight rings in 46 teeth are not abundant, but they're out there. That would give you a slightly higher top gear.
Another benefit to that setup: five-speed freewheels in that 14-32 combination were popular in half-step applications, so you might well be able to find an existing example, rather than having to assemble your own. And you'd keep the 120 dropout spacing.
EDIT: This one, for example:
https://www.ebay.com/itm/25517088792...8AAOSwcQxhYZ8P
Not hard to find, evidently--there are several others listed now as well.
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Last edited by jonwvara; 01-05-22 at 09:39 AM.
01-05-22 | 10:35 AM
#36
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Bikes: '38 Schwinn New World, '72 Peugeot PX-10, 78 Raleigh Comp GS, ’80 Peugeot TH-8 tandem
I may have mentioned this before, but the best gear calculator I have found is this one:
Bicycle Gear Calculator
Very easy to use and gives a nice visual representation of all the possible combinations.
*edit- Aha, I just noticed you can compare 2 setups in the gear-calculator.com one, too!
Last edited by ehcoplex; 01-05-22 at 10:42 AM.
01-05-22 | 02:59 PM
#37
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From: southern California
Bikes: 98 Trek 6000 MTB, 70's mutant St. Etienne
Happy Red Clover Triplizer user here! Now happily 52-42-30 front and 14-28 Maillard rear. Flattens out hills nicely. Upgraded the derailleurs and had to dig through hundreds of greasy bottom bracket spindles at the local Bicycle Kitchen Co-op to find a few 3N, 3S and 3T spindles that have the extra length on the drive side but forgot about that pretty soon with the greatly improved ride on this old French bike
Last edited by Medium Size Dog; 01-07-22 at 12:35 PM.
01-07-22 | 08:09 AM
#38
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Bikes: '38 Schwinn New World, '72 Peugeot PX-10, 78 Raleigh Comp GS, ’80 Peugeot TH-8 tandem
Quite certain I'll stick with the 93, but boy, the three-arm Touring Sport cranksets look cool. Anybody know what the smallest chainring available for them was?*
*(I assume not easy to find and $$$....)
EDIT- ah, nevermind, found Sheldon Brown's crib sheet. Looks like 35t.
*(I assume not easy to find and $$$....)
EDIT- ah, nevermind, found Sheldon Brown's crib sheet. Looks like 35t.
Last edited by ehcoplex; 01-07-22 at 08:21 AM.
01-07-22 | 10:03 PM
#39
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From: Los Angeles, CA
Bikes: 1964 Legnano Roma Olympiade, 1973 Raleigh Super Course, 1978 Raleigh Super Course, 1978 Peugeot PR10, 2002 Specialized Allez, 2007 Specialized Roubaix, 2013 Culprit Croz Blade
For what its worth, on my '78 PR10 I had a couple of gear set ups on it. I didn't like the original 3 arm Stronglight TS, which also had a stripped pedal thread. I had a Sugino GT crank (English pedal threads) laying around, so I tried it with a 52/34 compact set up, which worked out very nicely with the 28t 5 sp rear. The Sugino cranks can also be run as triples. At whenever the last Eroica California was, I found a drilled Stronglight 99 with English pedal threads, and grabbed it. I think it's a 52/36, still with the 28t 5 sp rear (French thread freewheel). I liked the look of the Sugino, but the drilled Stronglight 99 is more French sexy looking, though I miss the 34t granny. If you go to an English thread hub on your new wheelset, you can use a Shimano Megarange 34/14 6 or 7 speed freewheel, which I like very much on my Raleigh with the a Sugino AT triple 52/40/32 (dark green bike). Purists will shriek at the Shimano Megarange, but at 72 years old, still doing big hills, I don't care. You will need a long cage RD for the 34t, but its worth it. First picture is as bought.
Last edited by Slightspeed; 01-08-22 at 12:23 AM.
01-07-22 | 11:49 PM
#40
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From: Bastrop Texas
Bikes: Univega, Peu P6, Peu PR-10, Ted Williams, Peu UO-8, Peu UO-18 Mixte, Peu Dolomites
My vote is bikiniGreen 46/30 up front and a 6 Speed Freewheel 14-34 in back using a long cage derailluer. I have three of my bikes set up this way...
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01-08-22 | 06:55 AM
#41
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Bikes: '38 Schwinn New World, '72 Peugeot PX-10, 78 Raleigh Comp GS, ’80 Peugeot TH-8 tandem
For what its worth, on my '78 PR10 I had a couple of gear set ups on it......
Purists will shriek at the Shimano Megarange, but at 72 years old, still doing big hills, I don't care. You will need a long cage RD for the 34t, but its worth it. First picture is as bought.
Purists will shriek at the Shimano Megarange, but at 72 years old, still doing big hills, I don't care. You will need a long cage RD for the 34t, but its worth it. First picture is as bought.
I can't say I won't end up there, but man are those Shimano Mega-range freewheels fUGLY!
