# I've been had by NJS!



## onespeedbiker (May 28, 2007)

Correct me if I'm wrong, but has any one ever heard of an NJS Square Taper axle for a 73 mm shell. Lookie lookie here. I've been looking for a Shimano NJS ST axle and one finally showed up on ebay that I could afford. So I bought the sucker and it arrived today; the thing looked like it had never been installed. So I greased it up and tried to install it in my new Soma frame. Hmmm; it didn't fit. I thought the NJS standard was 68mm shell. I pulled it out and sure enough it's for a 73. Below is a photo of my new spindle, alond with a trashed 68 spindle and an old 73 spindle just for comparison. Just for kicks I took some pictures of the end with a bearing in it. As you can see, there is probably not enough spindle to attach a crank. And yes it is NJS stamped. Also marked "68=S=107"; doesn't that mean "68 shell=single chain ring= 107 mm wide"? What gives???

Brad


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## filtersweep (Feb 4, 2004)

Is this for your Soma? I don't get the NJS obsession for a non-NJS frame when you live nowhere near Japan. Not to threadjack, but this borders on the bizarre.


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## asterisk (Oct 21, 2003)

Strange, I don't think it's the 68/70mm difference... that's just the cup size (brit standard v. italian) but the 107mm... the 7600 sealed square taper NJS BB is 109mm and I didn't think there were any changes between the 7400 and 7600 models (aside from going sealed.)


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## onespeedbiker (May 28, 2007)

asterisk said:


> Strange, I don't think it's the 68/70mm difference... that's just the cup size (brit standard v. italian) but the 107mm... the 7600 sealed square taper NJS BB is 109mm and I didn't think there were any changes between the 7400 and 7600 models (aside from going sealed.)


Actually the difference between 7600 loose ball and sealed was huge. When Shimano went to the sealed BB, they also went to a splined interface and became the only NJS BB interface that is not ISO Square Taper. Also your ascertain


asterisk said:


> Strange, I don't think it's the 68/70mm difference... that's just the cup size (brit standard v. italian)


 is well wrong. The shell size is actually a different width and the threads are different between italian and brit.. You also missed the point I was talking about a 73mm shell, which is also “brit standard”. Yes the cups are different between 68 and 70mm, but they are the same for 68 and 73mm. The distance between the cones on the spindle, determines what width spindle it was made for. This is different from the older Shimano bottom brackets were the end cups determined the width of the shell for which is was designed to be used. The width of the spindle and it’s symmetry or lack there of, usually determines how many chainrings the spindle was made for. Campy and Shimano use a “S”; “SSS” means a triple, “SS” means a double and “S” or “Pista” means a single or track. 

Here’s the Point, NJS is a standard. There is no Italian NJS or Brit NJS or American NJS; there is only NJS. The NJS means every Shimano loose ball spindle stamped with NJS will be for a 68mm shell, have a 42 mm chainline and have an ISO square taper (all other Shimano square tapers are JIS). That is true of every spindle also made by Sugino, Hatta and Suntour; if it has the NJS stamp, it has to be made to that standard. Every frame with an NJS stamp is made with a 68mm shell. To answer _filtersweep’_s question, I have an ISO square taper crankset, similar cranks are (or were) made by Campagnolo, Shimano, Sugino, Miche and Suntour. I also like Shimano loose ball bottom brackets (okay, call me strange but I like doing routine maintenance on my bike) and like I said, the only ISO square taper spindle made by Shimano is NJS, that’s why I want the NJS version. 

Back to the original point of this thread. I now have a spindle stamped NJS that will not not fit in the 68mm shell of any NJS frame (or any 68mm shell for the matter). By definition it is not NJS so it should not have an NJS stamp. I was wondering if anyone on this board has any idea were it could have come from.

Brad


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## onespeedbiker (May 28, 2007)

filtersweep said:


> Is this for your Soma? I don't get the NJS obsession for a non-NJS frame when you live nowhere near Japan. Not to threadjack, but this borders on the bizarre.


 NJS is not just for NJS frames, it is based on a much older standard that is pretty much still in use today (ISO track). If you are a retro grouch like myself, NJS is the last bastian of loose ball bottom brackets out their. As I mentioned in my other responce, ISO square taper was the standard for track cranks and I happen to own one of the million or so cranks made to that standard. Right now I am using a Campy double spindle backwards because I can't find a Shimano spindle (the Campy BB is asymetrical). Of course with your reasoning I should only be using Campy if I live in Italy  

Here's the rub. If I buy an NJS spindle, I know it will be for a 68 mm BB (like all track spindles) it will have an ISO taper (not JIS) and will usually give me a 42 mm chain line (+or- 1mm depending on the crank). Putting an NJS stamp on a non-NJS spindle, makes about as much sense as putting a 68 stamp on a 73mm spindle. Neither make any sense at all. I was just hoping I could tap into the knowledge base here and find out if there was some starnge application for this that i have never heard of. 

Brad


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## asterisk (Oct 21, 2003)

onespeedbiker said:


> Actually the difference between 7600 loose ball and sealed was huge. When Shimano went to the sealed BB, they also went to a splined interface and became the only NJS BB interface that is not ISO Square Taper.


No, 7600 was still square taper. The Octalink spline track bottom bracket wasn't until the 7700 series.

I answered your OP late so I misinterpreted things. 

The spindle you have was for either the 10-pitch group which was under the NJS standard for a while or the Dura-Ace EX Track group. Both used 107mm spindles with BSC cups.

edit: Also, if all you are looking for is a loose ball, NJS, 109mm bottom bracket look for either the Sugino 75 or MS-68. Both are still being produced and available from any EAI dealer.


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## onespeedbiker (May 28, 2007)

asterisk said:


> No, 7600 was still square taper. The Octalink spline track bottom bracket wasn't until the 7700 series.
> 
> I answered your OP late so I misinterpreted things.
> 
> ...


 My bad, I always forget about the 7610 and I also forgot that 10 Pitch was NJS. So what I have is a 7500 spindle and 7400 cups; and they don't play together. Guess I'll send them back. Thanks loads, again I learned I know less than I thought!! 

Brad


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