Measuring up for a threadless BB

Yossie
Yossie Posts: 2,600
edited July 2013 in Workshop
Evening all

Just a quick one: I've been given a frame that needs a threadless bb - at the mo' its got no BB in it all so I can't take the measurement off that.

Does anyone know a quick way to work out which one I need: the 68mm part is sorted (thank you vernier calipers) but the width?

Its a Boardman Pro ali/carbon job (2009 ish? - the one that came with Dura Ace and Ritchey finishing kit)

I've done a Google but to no avail and we have no Halfords where I am!

Many thanks and kind regards

Yossie

Comments

  • nicklouse
    nicklouse Posts: 50,675
    read the info on parktools. it is all there.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Monty Dog
    Monty Dog Posts: 20,614
    Do you mean press-fit? If shell is 68mm wide, it's likely to be BB30.

    http://www.qbp.com/diagrams/TechInfo/FS ... tchart.pdf
    Make mine an Italian, with Campagnolo on the side..
  • Yossie
    Yossie Posts: 2,600
    Cool guys - thank you very much for the posts (I must admit that I couldn't find anything on Park Tools re threadless BBs though...)

    I mean a threadless bottom bracket like this one http://store.velo-orange.com/index.php/ ... ckets.html as the threads in the frame are shot and therefore I can't use a normal threaded BB: does this mean that a press fit will work as they don't use frame threads?

    Thank you again

    y
  • Monty Dog
    Monty Dog Posts: 20,614
    No, press-fit won't fit as they are too big in diameter for a regular BB shell. In terms of the right length of spindle, that's determined by the crankset so without knowing what cranks you're planning to fit, it's impossible to answer the question.
    Make mine an Italian, with Campagnolo on the side..
  • Yossie
    Yossie Posts: 2,600
    Ah - got you now.

    Its going to have either late 90s 105 or mid 90s whatever Ultegra was called then - SX600 I think offhand (unless I can track down some cool square taper cranks in the meantime).

    Basically its the "new" winter hack - last years 105 everywhere except for the cranks - I have everything in The Big Box of Bits in the garage so its a minimal spend rebuild.

    I presume then that its spindle length (ie 68mm) plus diameter of the crank arms?
  • Monty Dog
    Monty Dog Posts: 20,614
    Googling has revealed that for a 68mm shell, a Shimano 6200 crank used a 116mm spindle. A Shimano BB-UN55 in 115mm is probably your best bet.
    Make mine an Italian, with Campagnolo on the side..
  • Yossie
    Yossie Posts: 2,600
    Cool - thank you very much.

    The cranks are the 100s not the 600s: I presume the same spindle length?

    Thank you very much again for your help - very much appreciated.
  • Yossie
    Yossie Posts: 2,600
    68 x 116mm bought, copperslipped and fitted - perfect fit.

    Monty: you're a legend: thank you very much.

    Y

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