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Bicycle Mechanics - what size is my bottom bracket?

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ader220

11-07-07, 03:58 PM

I have an old Raleigh Record. I was wondering how I could find out what size my bottom bracket is because I am in need of a new one along with crank set and chainring. I'v had trouble finding information about the size since the Record is probably from the 80's. Is this model too old to install a newer(not used) bottom bracket or can I install any newly made bottom bracket which matches its size?
Thanks for any input you guys can help me out with.

ninjaman

11-07-07, 04:12 PM

Should be an English threaded 68mm shell, as were most 80's Raleighs. If you're unsure, it's much better to just take it to a shop and have them tell you than to blow cash on the wrong bb.

dizzy101

11-07-07, 04:23 PM

Borrow a crank puller from someone, pull the cranks, then unscrew the bottom bracket (officially you need tools for this, but I found a hammer and a screwdriver works too). Then take the bottom bracket apart and measure the length of the spindle (D). Also measure these sizes A, B and C:

http://www.sheldonbrown.com/images/spindle.jpg

Then go to Sheldon Brown's page (http://www.sheldonbrown.com/bbsize.html), and see which symmetrical bottom bracket is equivalent to the one you just pulled out. Order one, together with the tool you need to screw it in (probably a Park BBT-22, or a Pedro bottom bracket tool--these are 20-tooth BB tools)

Boom! You're done.

sivat

11-07-07, 10:55 PM

That's assuming that the frame isn't old enough to have the raleigh proprietary bb threading.

HillRider

11-08-07, 10:41 AM

That's assuming that the frame isn't old enough to have the raleigh proprietary bb threading.
A friend has a '72 Raleigh that has their proprietary threading (same diameter and thread directions as English but 26 tpi instead of 24). I don't know when they made the change to conventional English threading but it was after his was made. Sheldon Brown is an authority on older Raleighs and should know.

Sheldon Brown

11-08-07, 11:04 AM