Originally Posted by
bikemig
I have 4 bikes that need work. First up is a mid 70s Sekine SHS 271 with a full tange frame set (likely no. 3). I'm building up with original components; I'm trying hard not to modify it into some sort of gravel mutt because this bike can take humongous tires--700 x 38c easily--or swapping out the shimano parts (mainly titlist) for a crane RD and early dura ace stuff. It also has a weird 70mm english threaded BB; what the heck where they thinking in Canada when they spec'd this bike in Japan,

I'm thinking the product guys had one too many Molsons when they spec'd this bike out, : )
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wrt the LXX mm shell -
it is likely called a LXXI in JIS terminology as it is a copy of an old Brit dimension.
they are also found on numerous mounts from Flanderlandt.
not so weird as one moyte thimk.
btw - there be a possibility that the machine's chainset & bb spindle may be three degree taper...
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