BB Cartridge Spindle Length?
#1
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
BB Cartridge Spindle Length?
I’m refurbishing a c1978 Centurion Pro Tour. More of a resto-mod actually: new tubeless wheels with 9-speed cassette, triple crankset, etc.
I ordered a used Specialized Flag triple crankset that should be delivered next week. I’d like to make sure the bottom bracket is ready to go when it arrives. If the existing (excellent condition) cup and ball bottom bracket set won’t work, I want to move to a modern sealed unit.
Research suggests 115 - 125 mm spindle length for the Centurion’s 68 mm shell width for a triple crankset. The existing spindle is 124 mm (32 mm left, middle 53 mm, 39 mm right drive side). It has a 1 mm spacer on the right side between the cup and shell, presumably for the stock Suntour SR double.
Will the stock BB work with the Specialized triple (inner chainring clearance, chain line)? If not, what size cartridge would work?
Thanks.
I ordered a used Specialized Flag triple crankset that should be delivered next week. I’d like to make sure the bottom bracket is ready to go when it arrives. If the existing (excellent condition) cup and ball bottom bracket set won’t work, I want to move to a modern sealed unit.
Research suggests 115 - 125 mm spindle length for the Centurion’s 68 mm shell width for a triple crankset. The existing spindle is 124 mm (32 mm left, middle 53 mm, 39 mm right drive side). It has a 1 mm spacer on the right side between the cup and shell, presumably for the stock Suntour SR double.
Will the stock BB work with the Specialized triple (inner chainring clearance, chain line)? If not, what size cartridge would work?
Thanks.
#2
Senior Member
Join Date: Apr 2011
Posts: 7,067
Mentioned: 41 Post(s)
Tagged: 0 Thread(s)
Quoted: 4409 Post(s)
Liked 1,565 Times
in
1,027 Posts
Spindle length and type are dictated by the crank. Look it up in velobase or some other reference.
Likes For Kontact:
#3
Senior Member
Join Date: Jan 2019
Location: Toledo Ohio
Posts: 1,496
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
Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
Quoted: 583 Post(s)
Liked 699 Times
in
394 Posts
Others will say that ultimately you won’t know until you try it. That being said, my guess is it will work. I personally like the inner ring on a triple to be close to the chainstay.
Likes For sd5782:
#4
Senior Member
Join Date: Oct 2015
Location: PDX
Posts: 13,046
Bikes: Merz x 5 + Specialized Merz Allez x 2, Strawberry/Newlands/DiNucci/Ti x3, Gordon, Fuso/Moulton x2, Bornstein, Paisley,1958-74 Paramounts x3, 3rensho, 74 Moto TC, 73-78 Raleigh Pro's x5, Marinoni x2, 1960 Cinelli SC, 1980 Bianchi SC, PX-10 X 2
Mentioned: 267 Post(s)
Tagged: 0 Thread(s)
Quoted: 4512 Post(s)
Liked 6,387 Times
in
3,672 Posts
I’m refurbishing a c1978 Centurion Pro Tour. More of a resto-mod actually: new tubeless wheels with 9-speed cassette, triple crankset, etc.
I ordered a used Specialized Flag triple crankset that should be delivered next week. I’d like to make sure the bottom bracket is ready to go when it arrives. If the existing (excellent condition) cup and ball bottom bracket set won’t work, I want to move to a modern sealed unit.
Research suggests 115 - 125 mm spindle length for the Centurion’s 68 mm shell width for a triple crankset. The existing spindle is 124 mm (32 mm left, middle 53 mm, 39 mm right drive side). It has a 1 mm spacer on the right side between the cup and shell, presumably for the stock Suntour SR double.
Will the stock BB work with the Specialized triple (inner chainring clearance, chain line)? If not, what size cartridge would work?
Thanks.
I ordered a used Specialized Flag triple crankset that should be delivered next week. I’d like to make sure the bottom bracket is ready to go when it arrives. If the existing (excellent condition) cup and ball bottom bracket set won’t work, I want to move to a modern sealed unit.
Research suggests 115 - 125 mm spindle length for the Centurion’s 68 mm shell width for a triple crankset. The existing spindle is 124 mm (32 mm left, middle 53 mm, 39 mm right drive side). It has a 1 mm spacer on the right side between the cup and shell, presumably for the stock Suntour SR double.
Will the stock BB work with the Specialized triple (inner chainring clearance, chain line)? If not, what size cartridge would work?
Thanks.
Used cranks that have been in service will end up in different places depending on stretch, taper, wear, the sun, moon, tides, etc, etc.
This is where a co-op can be invaluable if you can grab a hand full of spindles to test fit, mix and match, etc which is what it usually takes to get there.
Plenty of info out there and many here have it down to a science but can always be hunt and peck.
I encourage you to stick with cup and spindle on this, experience you gain from this can be invaluable going forward.
#5
Senior Member
Join Date: Oct 2015
Location: PDX
Posts: 13,046
Bikes: Merz x 5 + Specialized Merz Allez x 2, Strawberry/Newlands/DiNucci/Ti x3, Gordon, Fuso/Moulton x2, Bornstein, Paisley,1958-74 Paramounts x3, 3rensho, 74 Moto TC, 73-78 Raleigh Pro's x5, Marinoni x2, 1960 Cinelli SC, 1980 Bianchi SC, PX-10 X 2
Mentioned: 267 Post(s)
Tagged: 0 Thread(s)
Quoted: 4512 Post(s)
Liked 6,387 Times
in
3,672 Posts
I usually get it right by the second stab.
#6
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
#7
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
You will need to test fit the crank when it gets here, no way to know for sure until then.
Used cranks that have been in service will end up in different places depending on stretch, taper, wear, the sun, moon, tides, etc, etc.
This is where a co-op can be invaluable if you can grab a hand full of spindles to test fit, mix and match, etc which is what it usually takes to get there.
Plenty of info out there and many here have it down to a science but can always be hunt and peck.
I encourage you to stick with cup and spindle on this, experience you gain from this can be invaluable going forward.
Used cranks that have been in service will end up in different places depending on stretch, taper, wear, the sun, moon, tides, etc, etc.
This is where a co-op can be invaluable if you can grab a hand full of spindles to test fit, mix and match, etc which is what it usually takes to get there.
Plenty of info out there and many here have it down to a science but can always be hunt and peck.
I encourage you to stick with cup and spindle on this, experience you gain from this can be invaluable going forward.
#8
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
Got the Specialized flag crankset. Surprise—the 124 mm spindle is too long! The inner triple chainring sits about where the SR double sat, but the big ring is ~5 mm too far out.
SR double crankset
Specialized flag triple crankset
The Specialized crankset has a ~7 mm “bump” protruding inboard.
Specialized on the left. You can see the “bump” that pushes the middle and outer chainrings out 5-7 mm.
I found this Specialized datasheet which calls for a 114.5 mm spindle for a 68 mm BB and Specialized triple. That would be ~9 mm shorter than the current spindle which seems excessive. Maybe with a symmetric spindle it would be correct?
SR double crankset
Specialized flag triple crankset
The Specialized crankset has a ~7 mm “bump” protruding inboard.
Specialized on the left. You can see the “bump” that pushes the middle and outer chainrings out 5-7 mm.
I found this Specialized datasheet which calls for a 114.5 mm spindle for a 68 mm BB and Specialized triple. That would be ~9 mm shorter than the current spindle which seems excessive. Maybe with a symmetric spindle it would be correct?
#9
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
I visited the LBS yesterday. They had a 115 and 125 mm cartridge and no spindles, so no luck.
Sooo…
At this point I’m thinking the easiest/most likely solution would be to find a new JIS spindle with 32-35 mm on the right side, so a 117 mm spindle with 32 mm left, 53 mm center, 32 mm right. No luck finding one online yet.
OR…
Should I just order a 118 mm Shimano cartridge and a few shims and make it work?
Meanwhile I’m going to install the 52/40 double to get it on the road. Who knows, mebbe I’ll grow me some quads!
Sooo…
At this point I’m thinking the easiest/most likely solution would be to find a new JIS spindle with 32-35 mm on the right side, so a 117 mm spindle with 32 mm left, 53 mm center, 32 mm right. No luck finding one online yet.
OR…
Should I just order a 118 mm Shimano cartridge and a few shims and make it work?
Meanwhile I’m going to install the 52/40 double to get it on the road. Who knows, mebbe I’ll grow me some quads!
Last edited by ACHiPo; 12-29-23 at 10:48 AM.
#10
Senior Member
I visited the LBS yesterday. They had a 115 and 125 mm cartridge and no spindles, so no luck.
Sooo…
At this point I’m thinking the easiest/most likely solution would be to find a new JIS spindle with 32-35 mm on the right side, so a 117 mm spindle with 32 mm left, 53 mm center, 32 mm right. No luck finding one online yet.
OR…
Should I just order a 118 mm Shimano cartridge and a few shims and make it work?
Meanwhile I’m going to install the 52/40 double to get it on the road. Who knows, mebbe I’ll grow me some quads!
Sooo…
At this point I’m thinking the easiest/most likely solution would be to find a new JIS spindle with 32-35 mm on the right side, so a 117 mm spindle with 32 mm left, 53 mm center, 32 mm right. No luck finding one online yet.
OR…
Should I just order a 118 mm Shimano cartridge and a few shims and make it work?
Meanwhile I’m going to install the 52/40 double to get it on the road. Who knows, mebbe I’ll grow me some quads!
Shimano lengths are very similar +/-0.5mm in most cases.
So a 118mm cartridge BB would move your DS in about 6mm and the NDS out about 1mm. These are estimates based on a 52mm center measurement, don't know where your measured lengths varies from the 52mm spec. It's somewhat difficult to determine exactly where to measure on the spindle.
Overall, for a crankset install, a couple of mm is irrelevant one way or the other. Unless the frame has clearance issues with the crankarm/chainrings, or FD range limitations, on a multispeed bike the chainline can work fine if it's close.
Likes For KCT1986:
#11
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
Attached is pic of the specs for Tange cartridge BBs and the aprox. length comparison to a cup/cone spindle (red #s). This is based on 52mm middle measurement (usual stated spec.).
Shimano lengths are very similar +/-0.5mm in most cases.
So a 118mm cartridge BB would move your DS in about 6mm and the NDS out about 1mm. These are estimates based on a 52mm center measurement, don't know where your measured lengths varies from the 52mm spec. It's somewhat difficult to determine exactly where to measure on the spindle.
Overall, for a crankset install, a couple of mm is irrelevant one way or the other. Unless the frame has clearance issues with the crankarm/chainrings, or FD range limitations, on a multispeed bike the chainline can work fine if it's close.
Shimano lengths are very similar +/-0.5mm in most cases.
So a 118mm cartridge BB would move your DS in about 6mm and the NDS out about 1mm. These are estimates based on a 52mm center measurement, don't know where your measured lengths varies from the 52mm spec. It's somewhat difficult to determine exactly where to measure on the spindle.
Overall, for a crankset install, a couple of mm is irrelevant one way or the other. Unless the frame has clearance issues with the crankarm/chainrings, or FD range limitations, on a multispeed bike the chainline can work fine if it's close.
Where can I find 1.37” ID shims? I find a bunch of options for smaller BBs.
#12
aged to perfection
Join Date: Jun 2009
Location: PacNW
Posts: 1,817
Bikes: Dinucci Allez 2.0, Richard Sachs, Alex Singer, Serotta, Masi GC, Raleigh Pro Mk.1, Hetchins, etc
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 839 Post(s)
Liked 1,258 Times
in
663 Posts
Get a phil 121 mm bb and solve your problem
/markp
/markp
#14
Senior Member
Did Phil have 121?
And of course the Phil is $180 when a Shimano is $20 or so.
Likes For KCT1986:
#15
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
Makes sense. If this turns into my forever bike, mebbe Phil is a possibility. As of now, I have about 3x more into this project than it’s worth. The $20 Shimano seems more attractive.
#17
Senior Member
If my mental math is correct, it sounds like you could flip the existing spindle and space the DS cup out by 1-2mm and it would work.
Likes For due ruote:
#19
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
I flipped the spindle this morning and voila! Even without the 0.5 mm spacer. Now the question is whether I can/should live with the Q of the left crank being out a little further than necessary? It seems like something I can fix down the road if/when I strip the paint and wrap the main triangle.
Thanks!
Last edited by ACHiPo; 12-31-23 at 11:41 AM.
#20
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
Awkward…
Just mounted the left crank and torqued both sides down. It definitely looks too far out. Oh well, I’ll add it to the punch list…
#21
Full Member
Join Date: Sep 2007
Location: seoul korea
Posts: 461
Bikes: 3Rensho SuperRecord Export, Bridgestones MB1 RB1 XO2, Colnago Super, Medici GranTurismo, Schwinn Paramount, Olmo Competition, Raleigh Portage, Miyata 1000, Stumpjumper, Lotus Competition, Nishiki Maxima, Panasonic DX6000, Zeus Criterium
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Likes: 0
Liked 82 Times
in
36 Posts
looks like maybe the velobase listed 115mm length could be closer to correct. to my eye the smallest chainring could still be pulled in closer to the frame even after flipping the spindle. i happen to prefer my cranks as close as reasonably possible on the drive and non-drive. i find the front derailleur shifts best when the small chainring is fairly close to the chainstay . but i use cup + cone and have a bin of nicer bottom bracket spindles i've collected over the years so i try one spindle i guess to be close (like you've done) take careful measurements and use the spindle that gets things as tight as possible.
so if my math is right you could move in the DS another 2-3mm so that's 32/53/30 = 115mm and also possibly move in the NDS as well (i haven't seen a photo of the clearance that 32mm would give you on the NDS) so it's possible the NDS and DS could also be 30 : 30/53/30 = 113mm
so if my math is right you could move in the DS another 2-3mm so that's 32/53/30 = 115mm and also possibly move in the NDS as well (i haven't seen a photo of the clearance that 32mm would give you on the NDS) so it's possible the NDS and DS could also be 30 : 30/53/30 = 113mm
#22
Junior Member
Thread Starter
Join Date: Oct 2023
Location: E. Bay, CA, USA
Posts: 120
Bikes: Trek 903, BMC Amp X 02, Criterion Pro Tour
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 40 Times
in
24 Posts
looks like maybe the velobase listed 115mm length could be closer to correct. to my eye the smallest chainring could still be pulled in closer to the frame even after flipping the spindle. i happen to prefer my cranks as close as reasonably possible on the drive and non-drive. i find the front derailleur shifts best when the small chainring is fairly close to the chainstay . but i use cup + cone and have a bin of nicer bottom bracket spindles i've collected over the years so i try one spindle i guess to be close (like you've done) take careful measurements and use the spindle that gets things as tight as possible.
so if my math is right you could move in the DS another 2-3mm so that's 32/53/30 = 115mm and also possibly move in the NDS as well (i haven't seen a photo of the clearance that 32mm would give you on the NDS) so it's possible the NDS and DS could also be 30 : 30/53/30 = 113mm
so if my math is right you could move in the DS another 2-3mm so that's 32/53/30 = 115mm and also possibly move in the NDS as well (i haven't seen a photo of the clearance that 32mm would give you on the NDS) so it's possible the NDS and DS could also be 30 : 30/53/30 = 113mm
I ordered a 115 cartridge. I’m pretty confident it will work well.
Last edited by ACHiPo; 12-31-23 at 10:31 PM.