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-   -   Fuji 1973 S10-S Bottom Bracket (https://www.bikeforums.net/classic-vintage/868661-fuji-1973-s10-s-bottom-bracket.html)

jtrem14 01-21-13 11:35 AM

Fuji 1973 S10-S Bottom Bracket
 
I've searched through all the related S10-s threads, and I can't seem to find any information that can help me out. I'm restoring a 1973 Fuji Special Road Racer. The issue I'm having is with the size and type of Bottom Bracket I will need. I know that normally BB's are either English threaded (68 or 73mm) or Italian threaded (70mm). the issue I'm having here is that my S10-S has a shell tube width of 70mm...but it is English threaded. I literally cannot find any information on the specifics of this bottom bracket anywhere.

Also, upon taking the unsealed bottom bracket apart, I noticed that the spindle is stamped with "3U". Sheldon Brown's BB guide seems to say that it should have a length of 124.5, but the length of the spindle is 127.5.

If anyone has any advice on what to do in replacing this bottom bracket, it would be greatly appreciated. I'd love to put a sealed BB in it, but I have no idea what size I could use, as the threading and size seems a bit contradictory.

RubberLegs 01-21-13 11:59 AM

There are threadless BBs available, but I am not seeing them in that length of spindle. May have to change crankset too....and then who KNOWS what the right length would be it!

jtrem14 01-21-13 12:05 PM

Velo Orange makes a threadless that comes in the 127mm length http://store.velo-orange.com/index.p...-brackets.html

I don't really understand how the threadless works. Would that work for me?

RubberLegs 01-21-13 12:11 PM

THIS may work IF you are 68- with English thread...great price to
http://www.bikepartsexpress.com/C173/CR5351.html

RubberLegs 01-21-13 12:13 PM

Don't know, I have never worked on a threadless BB, let alone a sealed bb unit...all my BBs are OLD SCHOOL!

Cougrrcj 01-21-13 12:15 PM

The crankset is a Sugino Maxy 3-pin cotterless. It the chainrings were very flimsy. I swapped mine ('75 S-10S) out years ago for a more modern Sakae SX triple, but I might have my old crankset/bottombracket in my parts bin. If I can find it, it is yours for the price of postage.

jtrem14 01-21-13 12:19 PM


Originally Posted by Cougrrcj (Post 15181785)
The crankset is a Sugino Maxy 3-pin cotterless. It the chainrings were very flimsy. I swapped mine ('75 S-10S) out years ago for a more modern Sugino triple, but I might have my old crankset/bottombracket in my parts bin. If I can find it, it is yours for the price of postage.

Cool, thanks. Is it a sealed BB? The stock, unsealed BB on it is in fine working order, apart from some rust (which can be fixed).

jtrem14 01-21-13 12:21 PM


Originally Posted by RubberLegs (Post 15181769)
THIS may work IF you are 68- with English thread...great price to
http://www.bikepartsexpress.com/C173/CR5351.html

Thanks. I had almost bit on a UN55 over the weekend before I actually decided to measure the shell tube myself. I had assumed it was 68mm by the look of it, and the way it threaded. But it is definitely 70mm. My concern with getting a 68mm BB is if there will be enough threads for the lockring to grab onto.

Cougrrcj 01-21-13 12:35 PM

No, the originals are NOT sealed. I went out to the barn (it is only 14*F here right now - Brrrrrrr) and found that I do still have the spindle itself, but I had re-used the original BB cups on my bike. The original crank arms/chainrings are in good shape as well, stamped Forged 171. Driveside arm has stamp of 47-4 and left arm has F-5.

BTW, pic of my bike as of last year - original paint, bars,stem,brakes and saddle. everything else has been replaced over the years.

http://i628.photobucket.com/albums/u...j/DSCF0120.jpg

Cougrrcj 01-21-13 12:51 PM

Just scrubbed my old spindle, and it has stampings of D-3SS and J-3 below that.

ThermionicScott 01-21-13 01:00 PM

The mix of a 70mm wide bottom bracket with English threading (and a spindle with a 55mm center section) seems to have been a Japanese thing. A couple of options:

1) have a trusted bike shop "face" the bottom bracket down to 68mm. There will be plenty of thread left, don't worry.
2) use a regular 68mm cartridge bottom bracket, plan on everything shifting to the right by 1mm and the left cup disappearing into the BB shell when torquing it down. This can work just fine if the aesthetics don't bother you. :)

jtrem14 01-21-13 01:14 PM

Wow, Thanks!

Courg, thank you so much for going out to your barn and checking on that. I appreciate the offer for the original BB and crank, but mine are in decent shape. I think I'm going to check out Thermionic's option. That is a great looking bike, too. Mine (which is my fathers old bike) isn't in nearly as good condition. It sat in a garage for the better part of 2 decades haha. So, I'm going to repaint it and put on new decals that I found. Thanks again!

Thermionic, thanks for the info! I just called my LBS and they are going to face it for me later in the week!

I'll post some progress pictures soon. Now I need to start figuring out the headset haha
Thanks again!


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