Bottom Bracket sizing??

Hell and High Water said:

Looking for a new crankset, I'd like something black, but not too
expensive. I'm not really finding what I'm looking for.

I've been told here that I need a 'square taper' crankset, as that's
what's on the bike....

NOW:

I'm thinking about getting a new bottom bracket. I thought if I got a
different type, maybe I might have an easier time finding a crankset.

Here's the bottom bracket I'd like to get:

http://tinyurl.com/8faab

Campy Veloce for $29!

and here's the crankset:

http://tinyurl.com/aqt2j

Black and decent looking for $29...

Now the big question:

Will these fit my older Bianchi Premio?

TIA!!!

In a word, this combination does not work. The BB is an ISO square
taper and that crankset requires an ISIS splined BB.

In general, what you need to do is find a crankset you want then buy
the BB for that crankset, making sure it fits in your bike frame. If
the crankset is designed for an ISIS splined spindle, your BB needs to
have an ISIS splined spindle. If the crankset needs a JIS square taper
spindle, your BB should have that type of spindle.

Once you have a match on the spindle types, if you are getting a new BB
there are a couple of things to which you will need to pay attention:

1) Shell width - this is either 68 or 73 mm for most bikes.

2) Threading - Most bikes sold in the US are BSC threaded (1.37 x
24tpi, with reverse thread on right side); there are Italian, French,
Swiss, etc. threading but the latter or rare these days and Italian
threading seems to be less common, too.

3) Spindle length - this value depends on the crankset.

It is most likely your current BB has a JIS square taper; easiest thing
to do is to buy a crankset that uses JIS square taper and uses the same
spindle length as your old crankset. If you want that Nashbar crank,
order an appropriate BB with an ISIS spline spindle.

- rick

Mon, 19 Sep 2005 16:48:11 -0500,
<[email hidden]>, Hell and High

Water said:

Looking for a new crankset, I'd like something black, but not too
expensive. I'm not really finding what I'm looking for.

I've been told here that I need a 'square taper' crankset, as that's
what's on the bike....

NOW:

I'm thinking about getting a new bottom bracket. I thought if I got a
different type, maybe I might have an easier time finding a crankset.

Here's the bottom bracket I'd like to get:

http://tinyurl.com/8faab

Campy Veloce for $29!

and here's the crankset:

http://tinyurl.com/aqt2j

Black and decent looking for $29...

Now the big question:

Will these fit my older Bianchi Premio?

The BB would fit if you just ordered the right length and thread type
for you frame. The present cups should have some hint as to their
thread type.

Note that there is a difference between J.I.S. square tapers and
I.S.O. square taper spindle. The BB you linked is I.S.O. and the crank
would most probably be J.I.S., if it weren't ISIS.

The crank will not fit the spindle of that BB you linked. You'd be
trying to fit ISIS cranks onto a square taper spindle. ISIS means it's
a splined spindle. Nashbar says to use 68x108mm ISIS BB with that
crankset.

Are you totally confused yet?
Try this:
http://www.sheldonbrown.com/bbsize.html
--
zk