Hello All,

I have an 1980's vintage bottom bracket axle with markings as shown bellow. What I would like to know for purposes of finding a replacement, is what do the markings on the 2nd and 4th lines mean?

Shimano
68 = T = 121.5
Japan VIA
D-3SS 1B
CrMo

Thank for your comments!

Hello it seems to me that 68 is the width of your BB shell which means you need 'english' threaded cups. 121.5 is the 'spindle' lenght measured from end to end (not counting the threads if you have nuts) d-3ss 1b is shimanos part number and cromo means it is chromoly steel

most any shop should be able to get you a great cartridge replacement

I can help with some:

68 means it's for a 68 mm wide bottom bracket shell which is the standard English road frame width and also on some MTB frames

The 121.5 is the end-to-end width of the spindle in mm.

Japan is obviously the country of manufacture. IIRC, VIA means "patented" but I'm not certain of that.

CrMo means Chrome-Moly and is the alloy steel the spindle is constructed from.

The D-3SS specifies an unsymetrical (the drive side of the spindle is longer) spindle in the length and bb shell width shown above.

Thank you BianchiGirl and HillRider. Your comments really helps. I have confirmed that the bottom bracket shell is 68mm long and that the length of the axle is 121.5mm and it is unsymmetrical.

This leads me to another question:

If the axle is unsymmetrical wouldn't I need to somehow specify the unsymmetrical measurements? What do I measure exactly, from end of axle to what? Or is this information coded on the axle?

Here's some pics of the bottom bracket axle I am measuring. It's in great shape but I can't use this particular axle to replacement my warn axle as it belongs to another identical bike.

https://picasaweb.google.com/Cadabyss...eat=directlink

Thanks!

If it's assymmetrical, then the "long" side will always be on the right. This makes clearance for the chainrings. There used to be a lot of variations in BB spindle length, but they're getting hard to find. If you want a cartridge bearing replacement, this YST will work:
https://www.biketoolsetc.com/index.cg...=YS-BB98868122
A half-millimeter change in spindle length is trivial- you may have to adjust the front derailleur a bit when you're finished.

Since I am restoring this bike, what I am really looking for, if I can find one, is a traditional cup and cone part. I found some interesting info in regards to symmetrical/non-symmetrical cup & cone bottom bracket axles at Sheldon Brown's site here:

https://sheldonbrown.com/bbsize.html#japan

My bb isn't completely worn out (yet), so I have time to look around. If I can't find a traditional one, then I'll update to something more modern. Thanks.

well you know what you, you can take your info and shop around the bike stores in your area or the internet. it may be easier in the long run to go with a cartridge, especially if you intend to ride this alot.

That's almost always correct. The operative word here is "almost". Case in point:

I have a '93 Trek 7000 MTB (bonded Al frame, rigid fork, hardtail, LX components, 68 mm bb shell.) that came with a Tange cup-and-cone bb with a 133 mm unsymmetrical bolted spindle.

The first time I overhauled it, I discovered the spindle had been installed "backwards" (long end to the nds) at the factory. I mumbled something about those incompetents in Wisconsin and proceeded to install it "correctly". Then I installed the crank arms only to find the nds crank arm hit the chainstay!

Apparently the stays are so fat a regular spindle wasn't long enough to clear them so Trek used a very long spindle and put the long end to the nds. The "short" end of the spindle was long enough so the chainrings and the crank arm cleared the chainstays on the drive side.

I eventually replaced the Tange with a Shimano cartridge bb but had to use a 127.5 mm spindle (the longest I could find) and the nds crank just misses the chainstay by about 4 mm.

Steve, I just noticed that you're in Stumptown. I've run into a couple places with collections of cup & cone spindles:

Citybikes (both locations on Ankeny)
CCC (Alberta & 17th)
Recyclery (SE 9th and other locations.

Back in the day, we'd tell people to bring in the part and we'd match it up- there's so many variations that looking at the part is the most reliable method.

I have a set of Shimano bottom bracket cups in my bin o' parts- I'll see what spindle goes with them. I've been running them with a Sugino 113mm spindle for a while.

Loose Screws still has some cup and cone bb parts. Here is a 124 mm spindle for any English cup set:

https://www.loosescrews.com/index.cgi...id=60230757966

Also, a generic English threaded cup set:

https://www.loosescrews.com/index.cgi...id=60230757966

I also have a set of SR English threaded cups in my parts box which are used but in excellent condition. Yours for the asking if you want them but you will have to source the spindle elsewhere.

BianchiGirl:
You're right, it would be easier to upgrade. I'm into vintage bikes and enjoy searching for period correct parts in order to keep them "vintage". But if I can't find them, I'll upgrade to keep the bike running.

HillRider:
I love reading your story about the "almost always" non-symmetrical bottom bracket situation. The links you posted were interesting too. I didn't realize that generic cup sets were available. And they look like a pretty good match to my original parts. Thanks for the offer on your SR cups. I might take you up on it but want to look a little more for Shimano setup.

Jeff:
Yes, I am in the Portland Metro area and have visited the bikes stores you mentioned several times. My experience has been the used parts they have are usually fairly worn. Sometimes however, you can find something in good or better condition. That's part of the treasure hunting fun. I'll have to check them out for bottom brackets. And I would be interested in your spare Shimano cups if they are in good condition. From what I can tell, my spindle measures 37.5mm on the left side, 52 in the middle, and 32 on the right.

Thanks everyone! : )

The last time I was at CCC they had a bin of new Specialized-brand BB spindles. It might take some digging, but that's the fun part of "This Old Bike".