need advice on Dura Ace 7400 NJS bottom bracket

[altec]

Hi,

Can someone advise me on NJS Dura Ace 7400 bb. I found out that NJS is a standard for track frames and which means that bb is BSA shell 68 and ISO square taper (not JIS which is a major square taper standard for Dura Ace 7400 bb). On ebay I found two types of NJS bb:

1) 68-112 which has NJS on both cups and NO NJS writing on the spindle
2) 68-109 which has NJS on both cups and also NJS writing on the spindle

Could someone knowledgeable advise me on this subject? Why the bb 68-112 has no NJS on the spindle? Why 68-109 has NJS on the spindle? Does it mean something for the user?

thanks a lot!

 

[altec]

What I found about 68-112 spindle (without NJS writing on the spindle) is that it is not symmetrical. The difference is 3mm so my best quess is the one signed 68-109 (with NJS writing on the spindle) is symmetrical version?

But what is the difference in using of both spindles with such a slight spindle lenght difference? Does someone know?