Dura ace 7402 crank spindle length difference

[fr188]

Hi there, Ive started a new vintage project , I'm renovating a 1977 Carlton professional MK5, I have a dura ace 7402 chain set like to fit hopefully it will be 8 speed 26/13 cassette, what I'm not sure about is the bottom bracket , do I go for a cheaper UN 55 cartridge bottom bracket 113mm or 110 mm spindle length,or I can get a dura ace 7410 cartridge with I believe a 103mm spindle length , what am I best to fit as there seems to be a big difference in spindle lengths .

 

[lpretro1]

You need to have a bb that is the correct length axle for your crankset - if it is too long you will not be able to set eh front derailleur to work properly

 

[fossyant]

The Dura Ace 7400 series is 103mm. I have the 7402 series cranks with the XTR/DA cartridge BB of 103mm. Bloody bomb proof they are.

 

[fossyant]

PS be careful running a 26T sprocket on the 7400 DA rear mech - you'll need the B screw tightened right up - it's right on the max. I have a 24T with a 53 x 39 front chain ring. I ran 21T max for years and I had to be careful sorting it out for 24T. It's a small mech, not for big cassettes.