Campag UltraTorque BB fitting Q

pliptrot
pliptrot Posts: 582
edited June 2007 in Workshop
I'm putting a new Campag c/set on the bike; UltraTorque. Judging by the assembly it seems the face to face dimensions of the bottom bracket are critical; otherwise the bearings will suffer heavy side loadings from compression or the whole assembly may be sloppy. What do you think? Is their any realistic tolerance in the system. It's Trek OCLV frame, from before external BBs. (I guess the Shimano design is more forgiving?)

Comments

  • monty_dogcp
    monty_dogcp Posts: 382
    So is your BB shell out of tolerance? Because the Shimano design has the faff of adjusting the bearing end-load, but with the ugliness of the pinch bolt and splines, it's more tolerant - but they still recommend facing the shell. As it's a once-only job, why don't you get it faced?
  • pliptrot
    pliptrot Posts: 582
    If the tolerance of the Campag BB was 68mm +/-0.1mm (which is in itself enough to imply reduced bearing life), and the BB was at the low end of this, getting it faced would only make things worse. I guess the question is, what have Campag done to allow for different FtoF dimensions, as I can see no adjustment from the marketing blurb.

    I will have the BB faced anyway, as it's never been done. (Over a grand on a frame and it wasn't prepped for headset or BB)!
  • Rogercp
    Rogercp Posts: 27
    I'm confused as to your problem. Installing an Ultra Torque chainset/BB could not be simpler. I have fitted several. It goes without saying that the BB should be faced as well as the threads being taped. As for width Campag specify a tolerance of +/- 0.8mm. If your BB is wider face it to within spec. or if after facing its outside of spec. by being to narrow fit a BB spacer to bring it into spec.

    If you don't have access to the tools to do this take it to your LBS or better still a frame builder.

    Sorry any LBS's reading this but I once saw a shop "mechanic" face some poor souls BB. It made me weep.

    Roger

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