BB Question

rubertoe Posts: 3,994
edited November 2012 in The workshop
my FSA megaexo is on its way out as it has a bit of play in it,

My question is relativly simple, can I swap this for any external BB or do i need another Megaexo?

I currently use a FSA Gossamer Pro chainset and was thinking of going for a cheaper BB providing it will fit.

Any recomendations for a replacement BB?
"If you always do what you've always done, you'll always get what you've always got."

PX Kaffenback 2 = Work Horse
B-Twin Alur 700 = Sundays and Hills


  • supersonic
    supersonic Posts: 82,708
    Shimano work fine with them.
  • nicklouse
    nicklouse Posts: 50,675
    with FSA nothing is simple. it depends on what version of the FSA bb is there.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • mtb-idle
    mtb-idle Posts: 2,179
    yup, check carefully. I have two worn mega exo cranks in my spares box and rather unhelpfully they each have different axle sizes (and therefore need different BB's).

    Here's the Mega Exo Gossamer crankset. Note the diameter of the axle, it's largish (the same as Shimano 105)


    and here's the Mega Exo Omega crankset. Again, note the diameter of the axle. It's much smaller than the other one :x


    Switch the whole thing to Shimano 105, much easier.
    FCN = 4
  • Before you go spending too much money (unless you fancy an upgrade anyway)..assuming the basic construction of their BBs is the same across the range, the plastic endcap of the BB itself is a tophat section. It wears away, allowing that sloppiness. Its a bit hard to explain, but certainly on the Omega, the cranks are running on the plastic of that tophat washer... not the bearing itself.
    You can buy them for a few quid each (sorry, can't remember where i got mine).
    If the cranks spin graunchily, then the bearings probably had it anyway