Compact crank for classic?
03-10-19, 08:27 AM
#1
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts
Compact crank for classic?
I am a crumbling relic who, in good weather, creeps about the roads on the beloved custom frame, which carried him to Cat IV glory back in the early 80s. Currently, it has a 7800 group, but experience with a new CX bike this winter has convinced me that I am simply not strong enough for 53/39 and probably never was. Hence I am looking for a modern, 110 mm BCD, crank that will accommodate 50/34.
Aesthetics (hotnesses) are important and I'd really like it non-black. Interoperability with the 10-speed rear is essential and it would also be nice if I could use the present BB. If I'm not mistaken, there's a 9100 item which might work. Cost is not a major object. Any other ideas?
Aesthetics (hotnesses) are important and I'd really like it non-black. Interoperability with the 10-speed rear is essential and it would also be nice if I could use the present BB. If I'm not mistaken, there's a 9100 item which might work. Cost is not a major object. Any other ideas?
03-10-19, 08:56 AM
#2
Should Be More Popular
Join Date: Dec 2007
Location: Malvern, PA (20 miles West of Philly)
Posts: 43,052
Bikes: 1986 Alpine (steel road bike), 2009 Ti Habenero, 2013 Specialized Roubaix
Mentioned: 560 Post(s)
Tagged: 2 Thread(s)
Quoted: 22598 Post(s)
Liked 8,925 Times
in
4,158 Posts
03-10-19, 09:05 AM
#3
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts
Yeah, saw that one and it makes sense. 7800 was NOS in 2014, so the BB has probably held up to my 150 lbs and pathetic output.
Last edited by MoAlpha; 03-10-19 at 09:08 AM.
03-10-19, 09:29 AM
#5
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts
03-10-19, 09:34 AM
#6
Advocatus Diaboli
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,636
Bikes: Merlin Cyrene, Nashbar steel CX
Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4733 Post(s)
Liked 1,532 Times
in
1,003 Posts
I am a crumbling relic who, in good weather, creeps about the roads on the beloved custom frame, which carried him to Cat IV glory back in the early 80s. Currently, it has a 7800 group, but experience with a new CX bike this winter has convinced me that I am simply not strong enough for 53/39 and probably never was. Hence I am looking for a modern, 110 mm BCD, crank that will accommodate 50/34.
Aesthetics (hotnesses) are important and I'd really like it non-black. Interoperability with the 10-speed rear is essential and it would also be nice if I could use the present BB. If I'm not mistaken, there's a 9100 item which might work. Cost is not a major object. Any other ideas?
Aesthetics (hotnesses) are important and I'd really like it non-black. Interoperability with the 10-speed rear is essential and it would also be nice if I could use the present BB. If I'm not mistaken, there's a 9100 item which might work. Cost is not a major object. Any other ideas?
https://www.peterwhitecycles.com/carmina.php
03-10-19, 10:54 AM
#8
Senior Member
Join Date: Jul 2007
Location: South shore, L.I., NY
Posts: 6,882
Bikes: Flyxii FR322, Cannondale Topstone, Miyata City Liner, Specialized Chisel, Specialized Epic Evo
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 3238 Post(s)
Liked 2,085 Times
in
1,181 Posts
Pretty sure you can't go lower than a 52 large ring on a 130 BD crank common to 53/39 systems. Maybe your crank is 110 BCD ?.
Thus a new crank and b-bracket (might as well, they are like $25)
Biggest limiting factor though is front derailleur location and can you drop down the derailer to get it into good shifting position for a 50 ring.
Braze-on brackets obviously cause the most headaches, clamp arounds are easy as long as the clamp will clear things like bottle cage bolts. With braze-on it's possible to rat file the slot on the braze on.. As well somebody makes an adapter for a braz-on that allows a lower position for the derailleur.
Thus a new crank and b-bracket (might as well, they are like $25)
Biggest limiting factor though is front derailleur location and can you drop down the derailer to get it into good shifting position for a 50 ring.
Braze-on brackets obviously cause the most headaches, clamp arounds are easy as long as the clamp will clear things like bottle cage bolts. With braze-on it's possible to rat file the slot on the braze on.. As well somebody makes an adapter for a braz-on that allows a lower position for the derailleur.
03-10-19, 10:58 AM
#9
Senior Member
Join Date: Nov 2015
Posts: 8,922
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 4717 Post(s)
Liked 1,882 Times
in
998 Posts
https://www.bike-discount.de/en/buy/...iABEgK4NPD_BwE
03-10-19, 11:01 AM
#10
Senior Member
Join Date: Jul 2007
Location: South shore, L.I., NY
Posts: 6,882
Bikes: Flyxii FR322, Cannondale Topstone, Miyata City Liner, Specialized Chisel, Specialized Epic Evo
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 3238 Post(s)
Liked 2,085 Times
in
1,181 Posts
Shimano made a 130BCD 50T chainring(I own one).
https://www.bike-discount.de/en/buy/...iABEgK4NPD_BwE
https://www.bike-discount.de/en/buy/...iABEgK4NPD_BwE
Thx, I never knew that or saw that anywhere. If I can find it it'll work great on my Soma triple.
03-10-19, 11:42 AM
#12
Senior Member
Join Date: Mar 2007
Location: SF Bay Area, East bay
Posts: 7,659
Bikes: Miyata 618 GT, Marinoni, Kestral 200 2002 Trek 5200, KHS Flite, Koga Miyata, Schwinn Spitfire 5, Mondia Special, Univega Alpina, Miyata team Ti, Santa Cruz Highball
Mentioned: 53 Post(s)
Tagged: 0 Thread(s)
Quoted: 1609 Post(s)
Liked 2,590 Times
in
1,224 Posts
03-10-19, 11:47 AM
#13
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts
Braze-on brackets obviously cause the most headaches, clamp arounds are easy as long as the clamp will clear things like bottle cage bolts. With braze-on it's possible to rat file the slot on the braze on.. As well somebody makes an adapter for a braz-on that allows a lower position for the derailleur.
03-10-19, 02:07 PM
#14
Senior Member
Join Date: Jul 2007
Location: South shore, L.I., NY
Posts: 6,882
Bikes: Flyxii FR322, Cannondale Topstone, Miyata City Liner, Specialized Chisel, Specialized Epic Evo
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 3238 Post(s)
Liked 2,085 Times
in
1,181 Posts
03-10-19, 09:18 PM
#15
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,629
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3871 Post(s)
Liked 2,568 Times
in
1,579 Posts
Shimano makes a 14-28 10-speed cassette. Usually marketed to juniors, but it would whack down the top gear without requiring you to touch the crankset. Probably run smoother, too. 
03-11-19, 07:14 AM
#16
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts
03-11-19, 08:47 AM
#17
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,629
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3871 Post(s)
Liked 2,568 Times
in
1,579 Posts
Hmm, maybe I was thinking of 14-25? https://www.universalcycles.com/shopping/product_details.php?id=4468&category=534
Could have sworn there was also a 14-28, but perhaps it was too niche for Shimano to keep it in production. Peter White sells Shimano-compatible TA cassettes in this similar gearing, but they're even more expensive: https://www.peterwhitecycles.com/ta-cassettes.php
Could have sworn there was also a 14-28, but perhaps it was too niche for Shimano to keep it in production. Peter White sells Shimano-compatible TA cassettes in this similar gearing, but they're even more expensive: https://www.peterwhitecycles.com/ta-cassettes.php
__________________
RUSA #7498
Originally Posted by noglider
People in this forum are not typical.
Last edited by ThermionicScott; 03-11-19 at 08:51 AM.
03-11-19, 09:02 AM
#18
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts
Hmm, maybe I was thinking of 14-25? https://www.universalcycles.com/shopping/product_details.php?id=4468&category=534
Could have sworn there was also a 14-28, but perhaps it was too niche for Shimano to keep it in production. Peter White sells Shimano-compatible TA cassettes in this similar gearing, but they're even more expensive: https://www.peterwhitecycles.com/ta-cassettes.php
Could have sworn there was also a 14-28, but perhaps it was too niche for Shimano to keep it in production. Peter White sells Shimano-compatible TA cassettes in this similar gearing, but they're even more expensive: https://www.peterwhitecycles.com/ta-cassettes.php
03-11-19, 10:31 AM
#19
Senior Member
Join Date: Jul 2015
Posts: 55
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
Maybe I'm missing something,but isn't the reason to go compact having lower low gears? The suggestions of changing out the 53 or getting a junior cassette would only lower the high gears. It would be a lot less expensive to just not shift up so high.....
03-11-19, 10:49 AM
#20
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts
The big cassette gets me another few teeth on the low end and more useful gears in the big ring, but yeah, it doesn't completely solve the problem. The 50 is less helpful.
03-11-19, 10:55 AM
#21
Senior Member
Join Date: Nov 2015
Posts: 8,922
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 4717 Post(s)
Liked 1,882 Times
in
998 Posts
The OP didn't originally say he needed very low gears to climb, only that he wasn't strong enough for his 53/39.
03-11-19, 12:10 PM
#22
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts
Both are true and a smaller big ring would indeed help with the flats.
03-11-19, 07:30 PM
#23
Senior Member
Join Date: Dec 2009
Location: Melbourne, Oz
Posts: 9,545
Bikes: https://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=152015&p=1404231
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 1528 Post(s)
Liked 718 Times
in
510 Posts
Don't forget, you can go down to 38t on 130.
If looks are a factor, nothing you replace a FC-7800 with will look as good...
If looks are a factor, nothing you replace a FC-7800 with will look as good...
03-11-19, 07:55 PM
#24
Have bike, will travel
Join Date: Feb 2006
Location: Lake Geneva, WI
Posts: 12,284
Bikes: Ridley Helium SLX, Canyon Endurance SL, De Rosa Professional, Eddy Merckx Corsa Extra, Schwinn Paramount (1 painted, 1 chrome), Peugeot PX10, Serotta Nova X, Simoncini Cyclocross Special, Raleigh Roker, Pedal Force CG2 and CX2
Mentioned: 46 Post(s)
Tagged: 0 Thread(s)
Quoted: 910 Post(s)
Liked 288 Times
in
158 Posts
See: https://www.bikeforums.net/classic-vintage/1167438-vintage-looking-9-10-11-speed-cranksets.html
03-11-19, 08:00 PM
#25
Thread Starter
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,233
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10167 Post(s)
Liked 5,860 Times
in
3,154 Posts