Classic & Vintage - Beveled bottom bracket shell, old Japanese frame

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KnhoJ
07-10-06, 03:23 PM
Look out, I'm crossposting! I tried the Mechanics branch of the forum without much luck, and it was recommended that I crosspost over thisaway.
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I know I've heard of these before. I just can't remember where, and searching isn't turning up anything.
So anyways, I'm slowly putting together a crusty old Mizutani Seraph. It turns out that the ends of the bottom bracket shell are beveled on the inside corner at about a 45 degree angle. It's far enough that the extra cartridge type bottom bracket I had lying around doesn't have a squared-off surface to seat against.
The bottom bracket that was in there was a cottered type. And by cottered, I really mean that it's being replaced with something cotterless. Any suggestions? If I'm outta luck, or just overlooking something stupid, heartless mockery will suffice.:D

you
07-10-06, 04:52 PM
switch the cottered spindle with a square taper spindle, check your local used bike shop or bike co-op.
KnhoJ
07-10-06, 06:03 PM
switch the cottered spindle with a square taper spindle, check your local used bike shop or bike co-op.
Well, the rest of the bottom bracket didn't come out usable. The bearing surfaces were pitted. I took no prisoners during the removal of the bottom bracket.

unworthy1
07-11-06, 01:07 AM
might be a long shot...or might be a match made in heaven: find a Mavic sealed unit that's intended to fit a BB shell with damaged or no threading. These have a chamfered lockring that's intended to fit a prepared BB shell with the inside edge chamfered to match...if you're lucky your shell might be ready-to-fit just as it is. There's also a cheap YKT sealed cartridge BB unit that is designed to do about the same job as the Mavic but without the shell chamfer, and it's not nearly the same quality...Bike Tools, etc. is one place that stocks the YKT; you may have to go eBaying for a Mavic.
unworthy1
07-11-06, 11:06 AM
correction: the cheap brand BB is a YST, and looking at the very small pic in the catalog, it seems to have reverse-chamfered surfaces on the fixed side as well as the locking ring. So maybe it's more like the Mavic BB after all...except for it being a cheap Taiwanese unit. Anyway, I still think it might be the perfect fix for your chamfered shell, if I understand the problem correctly. BTW, what's a Mizutani Seraph look like, anyway?
KnhoJ
07-12-06, 11:20 PM
BTW, what's a Mizutani Seraph look like, anyway?
Something like this. (http://portland.craigslist.org/bik/181398083.html) Except satin black, since that's the only powdercoat color that my employer has on hand, and Free is a Very Good Price. Originally it was some kind of pastel purply periwinkle with dark red primer showing in a spot or two. Thank God it's not that color anymore.
But I like to think of it more like this! (http://www.fixedgeargallery.com/2006/apr/JohnMcNeill.htm)
For the moment the plan is to set it up as a fixed gear.
Hey! I hear you yawning out there!
So I'm one of the 14 people left on earth who doesn't have one. And the frame has no provisions for cables or a rear derailleur. I'll come to my senses soon enough and realize I ride at least 9 miles through unavoidable hills to get to anything useful, and in the meantime I'll save up my pennies for an internally geared hub.