Cup & Cone BB Axle Length?

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quiksilver
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Joined: 13 Apr 2009, 9:38am
Location: Cornwall & London

Cup & Cone BB Axle Length?

Post by quiksilver »

I am thinking about replacing my cup and cone BB but am unsure of the correct points on the axle to measure to get the correct axle length? Is it the entire overall lenght including threads of the pedal retaining bolts or is the correct method the said overall length minus the threaded section at either end? Or is it some other distance? Help with this greatly appreciated,
Cheers :-)
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MikewsMITH2
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Re: Cup & Cone BB Axle Length?

Post by MikewsMITH2 »

Hi,
If you PM me with your email address I'll send you a table with all the dimensions and codes in.
Mike
S.O.S - Save Our Steel!
1971 Raleigh Mercury
2010 Condor Fratello
1980 Peugeot Tandem
1989 MBK Aventure MTB
195? Viking Severn Valley
1951 Raleigh Lenton Sports
See them here http://tinyurl.com/Mikewsmiths-Bikes
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meic
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Location: Caerfyrddin (Carmarthen)

Re: Cup & Cone BB Axle Length?

Post by meic »

Most Bottom Brackets do not have the studs sticking out of the axle.
So you measure to the end of the square taper part, putting the calipers on the shoulder rather than at the end of the threaded section.
The cartridge bottom bracket will most likely come with a pair of bolts to screw into the ends of the bottom bracket which will have a hole in it instead of a threaded stud sticking out of it.
Yma o Hyd
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MikewsMITH2
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Location: POOLE Dorset

Re: Cup & Cone BB Axle Length?

Post by MikewsMITH2 »

If you just want to replace the spindle, there's a bit more to it than that. You need centre width, short end and long end. 3 piece BBs are coded with a number(normally 3, 5 or 7) followed by one or 2 letters. If your spindle is stamped with such a code, then you can look for one with the same code. There is not a huge choice available now, but the table i have will enable you to find a close match.

If you want to replace it with one piece "cartridge BBs" you need to know your BB shell width and the axle length. If you have a british threaded BB then this is the simplest option. You may not always get the ideal chain line though. You also need to know if your spindle/cranks have a JIS (Japanese) taper or an ISO (French/Italian) taper as they are slightly different.

Also beware if youe bike is French, Italian or an old Raleigh as they have different BB threads
S.O.S - Save Our Steel!
1971 Raleigh Mercury
2010 Condor Fratello
1980 Peugeot Tandem
1989 MBK Aventure MTB
195? Viking Severn Valley
1951 Raleigh Lenton Sports
See them here http://tinyurl.com/Mikewsmiths-Bikes
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quiksilver
Posts: 275
Joined: 13 Apr 2009, 9:38am
Location: Cornwall & London

Re: Cup & Cone BB Axle Length?

Post by quiksilver »

Thanks for all the advice chaps.
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